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r oseleniaair traffic controlr a d a r s

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1

Schiphol.First airport in Europe

w i t h a n a u t o m a t i ca i r t raffic contro l

data-processingsys tem:

S c h i p h o l A m s t e r d a mS A T C O a u t o m a t i c

a i r t r a f fi c c o n t r o l

in fu l l opera t ion .

Main features of Signaai flight plan and radar data-processing systems.M a i n o p e r a t i o n a l f e a t u r e s

fl i g h t p a t h c a l c u l a t i o nc o o r d i n a t i o n

c l e a r a n c e p r o c e s s i n gc o r r e l a t i o n b e t w e e n r a d a r d a t a a n dfl igh t p l an da tac o n fl i c t r i s k d e t e c t i o n

c o n fl i c t r e s o l u t i o n

e l e c t r o n i c d a t a d i s p l a ysynthetic dynamic displaydaylight large screen displayflight progress boards t r i p p r i n t i n gautomat ic t rans fer o f da ta v ia datal i nks t o ad jacen t cen t res

P r o g r a m m i n g f e a t u r e sm o d u l a r d e s i g nfl e x i b i l i t yreconfiguration capabilitieson-line real-time programmingso f tware and ha rdware con t ro l l edmulti-level programming

C o m p u t e r f e a t u r e sm i c r o m i n i a t u r i z a t i o n t e c h n i q u e shigh operating speed1 microsec. memory cyclem a s s m e m o r i e s

h igh re l iab i l i t yg rowth po ten t ia lcon t inu i t y o f opera t ioneasy serv ic ing.

S I G N A A LFor further information please apply to N.V. Hollandse Signaalapparaten. P O Box 42, Hengelo, The Netherlands.

radar, weapon control, data handling and air traffic control systemsN . V . H O L L A N D S E S I G N A A L A P P A R A T E N H E N G E L O

The I n te rna t i ona l Fede ra t i on

of Air Traffic Controllers Associations

A d d r e s s e s a n d O f fi c e r s

A U S T R I A

Verband Osterreichischer FlugverkehrsleiterA 1300, Wien Flughafen, Austria, Postfcch 36P r e s i d e n t A . N o g yV i c e - P r e s i d e n t H . K i h rS e c r e t a r y H . B a u e rD e p u t y S e c r e t a r y W . S e i d IT r e a s u r e r W . C h r y s t o p h

B E L G I U M

Belgian Guild of Air Traffic ControllersAirport Brussels NationalZaventem 1, BelgiumP r e s i d e n t A . M a z i e r sV i c e - P r e s i d e n t M . v a n d e r S t r a a t eS e c r e t a r y C . S c h e e r sS e c r e t a r y G e n e r a l A . D a v i s t e rT r e a s u r e r H . C a m p s t e y nE d i t o r J . M e u l e n b e r g sIFATCA L ia i son O ffice r J .Ae lb rech t

C A N A D A

Canadian Air Traffic Control Association56, Sparks StreetR o o m 3 0 5Ottawa 4, CanadaP r e s i d e n t J . D . L y o nF i r s t V i c e - P r e s i d e n t R . M c F a r l a n eSecond Vice-President D. M. DiffleyM a n a g i n g D i r e c t o r G . J . W i l l i a m sT r e a s u r e r A . C o c k r e mChairman IFATCA Comm. R. Roy

D E N M A R K

Danish Air Traffic Controllers AssociationCopenhagen Airport — KastrupD e n m a r kC h a i r m a n E . T . L a r s e nV i c e - C h a i r m a n O . C h r i s t i a n s e nS e c r e t a r y E . C h r i s t i a n s e nT r e a s u r e r M . J e n s e nIFATCA Lia ison Officer V. Freder iksen

F I N L A N D

Association of Finnish Air Traffic Control OfficersSuomen Lennoniohtajien Yhdistys r. y.A i r Tr a f fi c C o n t r o lH e l s i n k i L e n t o

F i n l a n d

C h a i r m a n F r e d . L e h t oV i c e - C h a i r m a n V a i n o P i t k d n e nS e c r e t a r y H e i k k i N e v a s t eT r e a s u r e r A i m o H a p p o n e nD e p u t y V i l j o S u h o n e n

F R A N C E

French A i r Tra ffic Cont ro l Assoc ia t ionAssoc ia t ion Profess ionnel le de la Ci rcu la t ion Aer ienneB. P. 206, Paris Orly Airport 94F r a n c e

P r e s i d e n t F r a n c i s Z a m m i t hF i r s t V i c e - P r e s i d e n t J . M . L e f r a n cS e c o n d V i c e - P r e s i d e n t M . P i n o nGenera l Sec re ta ry J . Lesueu rT r e a s u r e r J . B o c a r dD e p u t y S e c r e t a r y R . P h i l i p e a uD e p u t y T r e a s u r e r M . I m b e r tI F A T C A L i a i s o n O f fi c e r A . C l e r c

G E R M A N Y

German A i r Tra f fic Con t ro l l e r s Assoc ia t i onVerband Deutscher Flugleiter e. V.3 Hannover-Flughafen, GermanyPostlagerndC h a i r m a n W . K a s s e b o h mV i c e - C h a i r m a n H . G u d d a tV i c e - C h a i r m a n E . v o n B i s m a r c kV i c e - C h a i r m a n H . W . K r e m e rS e c r e t a r y H . J . K l i n k eT r e a s u r e r K . P i o t r o w s k iE d i t o r L . G o e b b e l sI F A T C A L i a i s o n O f fi c e r W . G o e b e l

G R E E C E

Ai r Tra ffic Cont ro l le rs Assoc ia t ion o f Greece10, Agios Zonis Street, Athens 804, GreeceP r e s i d e n t C . T h e o d o r o p o u l o sV i c e - P r e s i d e n t N . P r o t o p a p a sGenera l Secre ta ry E . Pe t rou l iasT r e a s u r e r S . S o t i r i a d e s

H O N G K O N G

Hongkong Air Traffic Control AssociationHongkong AirportP r e s i d e n t A . A . A l l c o c k

S e c r e t a r y R . L . A y e r sT r e a s u r e r R . L o

I C E L A N D

Air Traffic Cont ro l Assoc ia t ion o f Ice land

Reykjavik Airport, IcelandC h a i r m a n G . K r i s t i n s s o n

S e c r e t a r y S . T r a m p eT r e a s u r e r K . S i g u r o s s o n

I R A N

I ran ian A i r Tra ffic Cont ro l le rs Assoc ia t ionMehrobad International AirportTeheran , I ran

Secretary General E. A. Rahimpour

I R E L A N D

I r i s h A i r T r a f fi c C o n t r o l O f fi c e r s A s s o c i a t i o nA T S S h a n n o n

I r e l a n d

P r e s i d e n t J . E . M u r p h yV i c e - P r e s i d e n t P . J . O ' H e r l i h yG e n . S e c r e t a r y J . K e r i nT r e a s u r e r T . L a n eA s s t . G e n . S e c r e t a r y M . D u r r a c k

I S R A E L

A i r Tr a f fi c C o n t r o l l e r s A s s o c i a t i o n o f I s r a e lP. O. B. 33Lod Airport, IsraelC h a i r m a n J a c o b W a c h t e lV i c e - C h a i r m a n W . K a t zT r e a s u r e r E . M e d i n a

I T A L ^

A s s o c i a z i o n e N a z i o n a l e A s s i s t e n t i e C o n t r o l i o r idella Civil Navigazione Aerea ItaliaVia Co la d i R ienzo 28Rome, ItalyP r e s i d e n t D r . G . B e r t o l d i , M . P .P r e s i d e n tS e c r e t a r yT r e a s u r e r

L . M e r c u r i

A . G u i d o n i

L U X E M B O U R G

Luxembourg Guild of Air Traffic ControllersLuxembourg AirportP r e s i d e n t A l f r e d F e l t e sS e c r e t a r y A n d r e K l e i nT r e a s u r e r J . P . K i m m e s

R H O D E S I A

Rhodes ian A i r Tra ffic Cont ro l Assoc ia t ionPrivate Bog 2, Salisbury AirportRhodesiaP r e s i d e n t C . W . D r a k e

S e c r e t a r y C . P . F l a v e l lT r e a s u r e r W . V a n d e w a a l

S W E D E N

Swedish Ai r Traffic Contro l lers Assoc ia t ionFack 22, Sistuna, SwedenC h a i r m a n L . B e r k e n s t a m .S e c r e t a r y A . K a r l a h a gT r e a s u r e r C . A . S t a r k m a nIFATCA Representative G. Atterholm

S W I T Z E R L A N D

S w i s s A i r T r a f fi c C o n t r o l l e r s A s s o c i a t i o n

V. P. R. S., P. O. Box 271CH 1215, Geneva Airport, SwitzerlandC h a i r m a n J . D . M o n i nS e c r e t a r y T . R o u l i n

T U R K E Y

Turk ish A i r Tra ffic Cont ro l Assoc ia t ionYesilkoy Airport, Istambul, TurkeyP r e s i d e n t A l t a n K o s e o g l u

U N I T E D K I N G D O M

Gui ld o f A i r Tra ffic Cont ro l Officers

14, South Street, Park LaneLondon W 1, EnglandM a s t e r A . F i e l d , Q B EE x e c u t i v e S e c r e t a r y W. R i m m e rT r e a s u r e r E . B r a d s h a w

N E T H E R L A N D S

N e t h e r l a n d G u i l d o f A i r Tr a f fi c C o n t r o l l e r sP o s t b o x 7 5 9 0

Schiphol Airport Central, NetherlandsP r e s i d e n t T h . M . v a n G a a l e nS e c r e t a r y F . M . J . M e n t eT r e a s u r e r P . K a l f fM e m b e r , P u b l i c i t y A . V i n kMember, IFATCA-affa i rs B. H. van Ommen

N E W Z E A L A N D

A i r Tr a f fi c C o n t r o l A s s o c i a t i o nDept. of Civil Aviation, 8th Floor, Dept. BIdgs.S t o u t S t r e e t

V^ellington, New ZealandP r e s i d e n t E . M e a c h e nS e c r e t a r y C . L a t h a m

N O R W A Y

Lufttrafikkledelsens ForeningBox 51, 1330 Oslo Lufthavn, NorwayC h a i r m a n G . E . N i l s e nV i c e - C h a i r m a n K . C h r i s t i a n s e nS e c r e t a r y J . K a l v i kT r e a s u r e r E . F e e t

U R U G U A Y

Asocia(;i6n de ControladoresAeropuerto Nacional de CarrascoTorre de Cont ro lMontevideo, UruguayC h a i r m a n U . P a l l a r e s

S e c r e t a r y J . B e d e rT r e a s u r e r M . P u c h k o f f

V E N E Z U E L A

Asociacion Nacional de Tecnicos enTrans i to Aereo VenezuelaAvenida Andres Bello, Local 78129 Caracas, VenezuelaP r e s i d e n t M a n u e l A . R i v e r a P .S e e r . G e n e r a l V . A l v a r e z . J i m e n e z

Y U G O S L A V I A

Jugoslovensko Udruzenje Kontrolora LetenjaDirekcija Za Civiinu Vazdusnu PlovldbuNovi Beograd, Lenjinov Bulevar 2Yu g o s l a v i aP r e s i d e n t

Vice-Pres identSecretaryT r e a s u r e r

M e m b e r

A. Stefanov icZ. VeresD. ZivkovicD. ZivkovicB. Budimirov ic

4

I F A T C A J O U R N A L O F A I R T R A F F I C C O N T R O L

T H E C O N T R O L L E RFrankfurt am Main, Jan./March 1969 Volume 8 • No. 1

P u b l i s h e r : I n t e r n a t i o n a l F e d e r a t i o n o f A i r T r a f fi c C o n

trol lers' Associations, S. C. II; 6 Frankfurt am MainN.O. 14, Bornheimer Landwehr 57a.

Officers of IFATCA: M. Cerf, President; J. R. Campbell,First Vice President; G. Atterholm, Second Vice President; G. W. Monk, Executive Secretory; H. Guddat,Honorary Secretary; B. Ruthy, Treasurer; W. H. End-lich. Editor.

Editor: Walter H. Endlich,3, rue Roosendael,Bruxelles-Forest, BelgiqueTelephone: 456248

Publishing Company, Production and Advertising SalesOffice: Verlog W. Kramer & Co., 6 Frankfurt am MainN014, Bornheimer Landwehr 57a, Phone 434325,492169,Postscheck Frankfurt (M) 11727. Rate Card Nr. 2.

Printed by: W.Kramer&Co., 6 Frankfurt am Main NO 14,Bornheimer Landwehr 57a.

C O N T E N T S

Subscription Rate*. DM 8,- p e r a n n u m ( i n

Contributors are expressing their personal points of viewand opinions, which must not necessarily coincide witht h o s e o f t h e I n t e r n a t i o n a l F e d e r a t i o n o f A i r Tr a f fi cControllers' Associations (IFATCA1.

IFATCA does not assume responsibility for statementsmade and opinions expressed, it does only accept responsibility for publishing these contributions.

Contributions ore welcome as are comments and criticism. No payment can be made for manuscripts submittedfor publication in "The Controller". The Editor reservesthe right to moke any editorial changes in manuscripts,which he believes will improve the material withoutaltering the intended meaning.

Written permission by the Editor is necessary for reprinting any part of this Journal.

RICA 1968 Annual Assembly Meeting

Controller Manpower and Training . .F. Lee Bailey

ATC Automation in the U.S.A. . .F e r r i s j . H o w i o n d

ARTS In-Service ImprovementsJ . Mi l ton Hatche l l

Area NavigationRobe r t W. Ma r t i n

Collision Avoidance Systems . .F r a n k C . W h i t e

Digital CommunicationsB. F. McLeod

An Airport Surface Traffic Control SystemL o u i s . A c h i t o f f

' C A T C A ' 6 9 "

1968 — an ac t ive Year fo r the Nether lands ' Gu i ld

Advertisers in this Issue: Seleni S.p.A. (Inside Cover);The Decco Navigator Co., Ltd. (Back Cover); DeutschePhilips GmbH (Inside Back Cover); Elliot Space andWeapon Automation Limited (1); N. V. HollondseSignaalopporaten (2).

Picture Credit: Vickers (28, 29); The Yugoslav Air TrafficController's Association (7); The Yugoslav Consulate,Brussels (7).

Pacific SAR SymposiumTirey K. Vickers

W h a t ' s N e w i n M o n t r e a l ?

Airlines Launch ATC Study .

Digital ATC Simulator for Eurocontrol Institutefor Air Navigation Services

5

Corporation Membersof the Internat ional Federat ionof Air Traffic Controllers' AssociationsThe Air Traffic Control Association,Washington D. C., U.S.A.The Air Transport Association,Washington D. C., U.S.A.Wolfgang Assmann GmbH., Bad Homburg v.d.H.Compagnie Generale de Telegraphie sans FilMalakoff, Paris, FranceCossor Radar and Electronics Limited,Harlow, EnglandThe Decca Navigator Company Limited, LondonELLIOTT Brothers (London) LimitedBorehamwood, Herts., EnglandF E R R A N T I L i m i t e dBracknell, Berks., EnglandGlen A. Gilbert & Associates,Washington D. C., U.S.A.IBM World Trade Europe Corporation,Paris, FranceInternational Aeradio Limited,Southall, Middlesex, EnglandITT Europe Corporation, Brussels, BelgiumJeppesen & Co. GmbH, Frankfurt, GermanyThe Marconi Company Limited Radar DivisionChelmsford, Essex, EnglandN.V. Hollandse SignaalapparatenHengelo, NetherlandsN.V. Philips Telecommunicatie IndustrieHilversum, HollandThe Plessey Company LimitedChessington, Surrey, EnglandSelenia - Industrie Elettroniche Associate S.p.A.Rome, ItalyThe Solartron Electronic Group, Ltd.Farnborough, Hants., EnglandTelefunken AG, Ulm/Donau, GermanyTexas Instruments Inc., Dallas 22, Texas, USAWhittaker Corporation,North Hollywood, California, USA

The International Federation of Air Traffic Controllers' Associations would like to invite all corporations, organizations, and institutions interested in and concerned with the maintenance and promotion of safety in air traffic to join their organization as Corporation Members.

Corporation Members support the aims of the Federation by supplying the Federation with technicalinformation and by means of an annual subscription. The Federation's international journal "The Controller" is offered as a platform for the discussion of technical and procedural developments in thefi e l d o f a i r t r a f fi c c o n t r o l .

Bd t̂cuU8 t h A n n u a l I FAT C AC o n f e r e n c e

2 4 / 2 8 t h M a r. 1 9 6 9H o u s e o f Yo u t h

House of Youth, the venue ot theC o n f e r e n c e

The building ot the YugoslavFederal Assembly at night

Be lg rade A i rpo r t

RTCA1968 Annual Assembly MeetingM e e t i n g t h e d e m a n d s o f e v e r - g r o w i n g

a i r t r a f fi c v o l u m e w a s t h e m o t t o o f t h e 1 9 6 8Annual Assembly of the Radio Technical Commission forAeronautics, which was held from September 25th/26th atthe Statler Hilton Hotel, Washington, D. C.

The theme of the Conference was broken down intof o u r a r e a s :

1 . T h e R & D e f f o r t

Scope: Current and planned R&D effort and programsi n t h e fi e l d o f a v i a t i o n e l e c t r o n i c s a n d t e l e c o m m u n i c at i o n s .

2 . A i r T r a f fi c C o n t r o l

Scope: Some answers — and questions — on what isbeing done or planned to increase the capability ofa i r t r a f fi c c o n t r o l .

3 . C o m m u n i c a t i o n s

Scope: What are the plans or programs dealing withcommunications via satell ite, digital communications,and public air/ground telecommunications?

4. Aircraf t Operat ionsScope: What is being done to satisfy V/STOL requirements, provide airport surface guidance system and onCollision Avoidance Systems (CAS) / Pilot WarningIndicators (PWI)?

All subjects were covered by an impressive number ofexcellent papers, some of which are reprinted in this issueo f ' T h e C o n t r o l l e r " .

The RTCA was assisted by an illustratious gathering ofexpert Speakers and Panel Members, and such distinguished Modera to rs as

Frank W. LehanAssociate Secretary for Research & TechnologyDepartment of Transportation

O s k a r B a k k e

Assoc ia te Admin is t ra to r fo r P lansF e d e r a l Av i a t i o n A d m i n i s t r a t i o n

Maj. Gen. J. Francis Taylor, Jr.USAF (Ret.)Senior Vice President — PlanningAeronautical Radio, Inc.

George B. LitchfordAv i a t i o n C o n s u l t a n t

stimulated the lively discussion.Wayne W. Parrish, President of America Aviation Pu

blications, Inc. was Guest Speaker at the RTCA Luncheon.Untiring J. R. "Dick" Campbell, First Vice-President of

IFATCA, represented the Federation at this most interesting Conference.

Control ler Manpower and Train ing

Mr. Bakke has explained my intrusion into the businessof Air Traffic Control as something other than a user of thesystem. It is recent; last January, to be precise, but it hasbeen most intensive. I probably have shaken the hands offour or five thousand of the traffic controllers in everymajor facility in the country and some minor facilities. Theoriginal purpose of the organization is to solve some ofthe problems confronting the controller as an individual.The heart of the system, no matter how many computers orautomated cockpit systems we are able to install and depend on, nonetheless, is the human hand and the humanvoice somewhere down on the ground in a shaded roomor in a control cob. Just as no one has thought to diminishthe importance of skilled judgment and highly specializedtraining on the part of the pilot simply because Mr. Learand others have built us auto-pilots that can drive youdown the glide-slope just about as well as any human cando it, the same is true of Air Traffic Controllers. No matterhow sophisticated the system may become, there is alwaysthe possibility of malfunction in some areas, perhaps theprobability, and then we've got to depend on somebodyusing techniques that rely on that 180-pound unskilledlabor computer* that we alluded to a little while ago.

Now, who is the Air Traffic Controller today? Why arewe in short supply? Where are we going to get some

See page 13, ATC Automation in the U.S.A.".

By F. Lee BaileyE x e c u t i v e D i r e c t o r o f t h e

Professional Air Traffic Control lers ' Associat ionto the 1968 RTCA Annual Assembly

more, and what ought they to be? These ore some of theproblems that we have confronted, digested and tried topresent to the aviation industry to try to get some feedback on them, because early in 1969 we hope to presentto the Congress some legislation to rectify problems wesee sitting right on the edge of the horizon, and some ofthem perhaps could be directly described as being in ourlaps. The Air Traffic Controller today, if nothing else as acommon denominator, is a young man, especially inhigh density areas. We have seen a number of studieswhich have been made by psychologists, psychiatrists andother specialists in the business of human stress and mental drain, to find out why this is so. We know empiricallythat this is so.

One of the pieces of evidence upon which I rely is theboard of directors of this organization which consistsentirely of working controllers and which has an averageof thirty-three years and eight months in age. On the otherhand, we don't find too many of them who ore workingfront-line positions and the boards at ffty. We know verywell that a fifty year old pilot is more than capable andprobably as good as he will ever get, so, there is a disparity there.

We have tried to compare the Air Traffic Controllerwith his compadre at the other end of the system. Weknow that any skillful pilot, well-equipped with avionics

8

and ground aids, con get his plane anywhere in the Golden Triangle without anybody's help. The problem is thathe can't get there without encountering someone elsealong the way. The odds sharply increase every day thatthat encounter will take place — were it not for someseparation not accomplished from the cockpit.

The Air Traffic Controller, then, is properly described,I think — as the Australians formally describe him — andthat is as The Separator. Without his separation function,the very busy airways of the United States could becomea holocaust all of a Tuesday afternoon. Now, unlike thepilot, whose business has been described perhaps jokingly,and perhaps seriously, as "hours of boredom punctuatedby a crisis at either end", the working day of the Air Traffic Controller at the high density facility is likely to behours of panic punctuated by a little bit of boredom — ifhe gets time off for lunch. So, one of the qualities that weknow he needs in order to exist is a great degree of resilience. And probably the requirement of that resilienceis one of the explanations for the average age of thefront-line working controller. On the other hand, simplyburning men out in their early-to-middle-age is not anadvantageous way to attract the best personnel to thesystem or to be left with a bunch of people that have togo somewhere sometime after that age has gone by. Sowe first turn our senses to what might be done to alleviatethese pressures and see whether or not we're going to relyon that alleviation to the extent of abandoning techniqueswhich, some years ago, were considered to be mandatory.

When I learned to fly instruments, and I'm sure whenmany of you did, we took the static-laden low-frequencyrange and tried to distinguish an A from an N and wewould try to give the controller a "guesstimate" of wherewe thought we were, and, if he was on the ball, he'dcome back and report somebody else thought he wasin the same place and we'd better watch out what wasgoing on. But that doesn't work anymore. The reliability,the reliance, indeed has necessarily shifted from the cockpit, where in many circumstances and certainly in the soup,we're all but helpless to accomplish any kind of separation. Insofar as the jets are concerned, because of thehigher rate of speed and the opposing speeds, again we'realmost helpless to depend on visual separation; which Iassume prompted the FAA to rule that everybody abovecertain plateaus would be under positive control and thusinsuring the separation which they couldn't guaranteethemselves. I foresee the day when 90% of all traffic anywhere near a high-density zone has got to be under somesor t o f cont ro l .

The maddening thing about today's air traffic system,and the most puzzling circumstance confronting a controller, is the mixture of traffic. I'm sure that pilots feelpretty much the same way. They are continually beinggiven what are euphemistically called Advisories — "Youhove traffic at 12:00 o'clock; altitude and speed unknown".Slow moving or fast moving — he's squawking VFR or he'sa primary target — but the pilot's head immediately goeson the swivel. And he may well be looking for somebodywho is miles away by vertical separation, but that uncertainty certainly does not militate in favor of the kind ofprecision that is going to be needed, if anything like theprojections of increased traffic come true. I tend to thinkthat all these projections are underestimated. Certainly, asof some years ago it was not the many, but the few that

c o u l d s e e t h a t w e w o u l d b e a t s a t u r a t i o n i n c e r t a i n a r e a s

today.The best evidence of saturation became dramatically

apparent last July, when in the peak season of travel inthe New York / Chicago and other areas, the controllerswho had had just about enough of the so-called "man-made rule on separation" began looking for a commonguideline and simply went back to the rulebook. As yourecall, the press began to search for the cause for whatwas termed initially a "slowdown". First reports suggestedthat the Administration was blackmailing the Congress.The next report said that the controllers were blackmailing the Administration. Indeed, when I walked in 45 minutes late to a conference with General McKee and a greatnumber of others at the roundtable in the FAA Building,he said to me in an aside, "Lee, I think you've been hoiston your own petard", because United Airlines was 45minutes late. But in looking back, I think that the picturehas fairly well developed despite the rather caustic comments of the rich man's Joe Pyne, which calls itself TimeMagazine. Nobody was calling a slowdown for higherpay. Indeed, higher pay wouldn't cure anything for anybody. It's just one facet of the system that may deserve alittle attention, in conjunction with all the rest.

Our controllers today came largely from the military— although not all. Some were military pilots, many weremilitary controllers, some have been given on-the-jobtraining. Most of those in the business regard this as anunsatisfactory way in which to indoctrinate someone intothe complex and precise business of Air Traffic Control.Recently, we were informed that the educational institutionat Oklahoma City has been re-opened after some years ofnapping and that some controllers are going to be trainedthere formally.

The programs of this training are something aboutwhich the working controllers today hope to hove somesay, because the programs are of extreme importance.First of all, we will need to do some screening. I don'tbelieve, and I don't think the controllers believe for oneminute, that everyone is adapted to this kind of work.There are certain people in my primary profession (whichis fastly receding to a secondary profession) who are notadapted to do trial work. The punch-ond-go, as we call it— the moment-to-moment decisions which con never beanticipated or planned out, but must be made and foreverlaid to rest, no matter how aggressively they may havebeen made — simply emasculate the methodical peopleto the point where they begin to get ulcers and heartattacks in their mid-30's. Regarding this as unsatisfactory,they go to the infinitely more profitable business of representing corporations such as yourselves. Fiowever, except for occasional anti-trust violations, I see very little ofthat action, I might point out.

But, psychological testing of some kind, I m sure, canbe formulated to see whether or not a man can acceptmultiple flight patterns at one time. Now the commanderof the airplane has his co-pilot — a luxury that I thinkmost controllers would like to have, a co-pilot. Indeed, hewould like to have also the luxury of back-up systems. Ican't think of anything I have in my Lear Jet that I don thave two of, sometimes three — including the stewardii.But, if the controller's radar goes out, he is unlikely to beable, at the present time, to switch on another set, because,due to frugality imposed upon us through various armedconflicts, crime in the streets and other small problems of

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the United States, the Congress has been unable to furnishus with the back-ups. But 1 think they are essential. Nonetheless, there is no way to count upon their always working. I doubt that many of those who fly professionally andhold the highest ratings would ever like to be put to thetest; but, it says somewhere in the book that we can comestomping down the ILS at 200 feet and a quarter mile onpartial panel — just the turn-and-bank and magnetic compass, if everything else goes out. Well, this is something Idon't wont to find out, but it is in the book. By the sametheory, the Air Traffic Controller today, and even more soin the future, must have that wide range of flexibility thatwill allow him to be abandoned by his computers and thenby his radar and still leave the airplanes in the sky withreasonable anticipation of landing on the rubber insteadof some other way. We've had some controllers recentlyup in that — well, you can call it an area, I suppose —around New York. It may be the Golden Triangle in somebody's book; we call it "Nightmare Alley". But with six orseven planes on vectors — which is strictly controller'sseparation — without reference at that time to any nav-aids, when the radar goes out, the best thing the controller can do at that time is dive head-first through theset and hope that he won't be alive afterwards. We havehad a man that we have been trying to interview, becausehe lost his radar with nine people at vectors all within 500feet of one another. I ask you to reflect to yourself — whatdo you do at that point? Is it reasonable to suggest thatplanted within the memory is the exact position of eachaircraft, including its heading, speed and altitude andtype, to the point to where you con track it mentally andmaintain that separation in your mind's eye and thentransmit it individually to each of the captains as you goalong until such time as the radar comes back in. We thinknot. Nonetheless, these failures must always occur.

Is the instrument pilot proficient with the turn-and-bankand the compass? Most of them who go up now and try tofly a little of it would find they are a bit rusty. Is the controller proficient, with his heavy reliance on radar, in airtraffic procedures — the manual support of controllers,where voice reports are relied upon for position from theaircraft, rather than the target which can be seen by thec o n t r o l l e r ?

We should screen out those who are unlikely to be ableto take the continuing pressure — and this is thegreatest distinction, I think, between flying and workingthe radar scope or the control cab (there isn't much difference in those jobs as far as pressure is concerned). Whenwe level off and begin to cruise, in the absence of extraordinary circumstances, it's usually time to begin to thinka b o u t t h e e s t i m a t e o f t h e d e s t i n a t i o n , t h e w e a t h e r t h a tis going to confront us there, the young lady we hope tofind and the mix ture o f co f fee we want to o rder f rom the

galley — because it's not a strenuous occupation. But thebusiness of control i s — hour by hour by hour by hour.And the worse the weather gets or the worse the intrusionof the unexpected into the system, like a mass of thunderstorms wandering through the New York area — will hebe able, will he be ready to handle that kind of system?Can he create suddenly four new fixes — not marked byany navaid and without the hope for area navigationalequipment, which will enable the pilot to see those fixesin the cockpit — and still handle all the airplanes he hasthen running in the stack; which he has promised the Cleveland, Washington and Boston centers he's going to land

sometime within the next two hours, so that he can takesome of the stacks that they've piled up waiting to get intoh i s a r e a ?

Education of the controller has got to include certainlya good, sound rounding-out in all the machinery uponwhich he will rely. That is to say, the communications ofthe network; how it works and what he can do when it isn'tworking right. How to recognize the kind of defect thatought to cause immediate switchover and howto recognizethe kind you can live with until the maintenance man canbe grabbed by the collar and set to work with his littlescrewdriver. The same goes with the radar. If he's to usecomputers, I think it mandatory that he understands whatthe computer is doing, because when the computer eitherm a l f u n c t i o n s o r r e f u s e s t o f u n c t i o n a n d h e h a s t o s u bstitute himself for it, he must know what duties he is takingover. I can visualize without much difficulty a tremendousaid from computers and a great relief of the pressure forcontrollers. I think that this is the best hope that we willstretch their useful life. The absence of continuing pressure, even though it may occasionally occur, will put himin the realm of the professional pilot who is given somem o m e n t s o f r e l a x a t i o n b e t w e e n h i s m o m e n t s o f l a b o r i n

the course of an ordinary "ffight.I think that computers are probably better than any

thing else, if there is fed to them the information whichunder the alpha-numeric system will appear on the scope,namely: the identity and type, the altitude (which is themost critical thing today that the controller must rely uponhis memory for — perhaps the greatest strain and thegreatest sweat). I say that because when two targets converge on a scope the controller knows that separation hasbeen lost laterally and longitudinally. If there is not vertical separation — there isn't any separation. And withoutseparation, there is an unexpected descent to earth — notin a way programmed by the aircraft manufacturer. Henow must remember those alt i tudes. If he misremembers —whereas a pilot's error will usually cost us one airplane, acrew and a load of passengers — that controller's errorwill cost us two. And he badly needs, and hopefully willget, just as soon as the government can loosen up with themoney and then the production, the system of alpha-numerics which will initially provide him with altitudeinformation and subsequently with all the other goodiesthat he would l ike to have.

I think, and the controllers who fly agree, that controllers should be pilots.There are several advantages emanating from this condition which are not enjoyed by thosewhose sole contact with aviation is a microphone and aradarscope. The advantages, which I envision are these(and we tested them out by putting some of the controllersin the airplanes and letting them see what they are doingto us and what we are doing to them when we get changesof clearance with one engine and a field of 200 feet anda quarter mile): The controller who can fly and can understand the flight deck knows what is going on, he knowswhat "reduce to 150 knots" means, or may mean, heknows what a 360 degree turn under certain conditions ata panic rate, which he may be requesting, means or maymean, and, most important of all, he knows what confrontsthe pilot when on emergency occurs. Because between thepilot and the controller there is but one chance to getthe airplane on the ground in most emergencies. Theopportunity or time to reconsider does not ordinarily present itself. In order to clear the proper air space, in order

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to give the pilot as much air as he needs, to allow him topre-empt it, to get his crippled bird on the ground, thecontroller should then be able to envision, not only thered fire-light that just came on, but the position of thegyros, the air speed, the fuel load and all the other thingsthat affect decisions made much too rapidly to be patiently explained to the guy on the ground as justifying theneed for some special treatment.

All these things would help, but of equal importancewould be the ground school that accompanies any kind offlight training. Now, I don't say every controller shouldhave an ATR, although that would be helpful. But heshould certainly understand all that a pilot understandsfrom a ground school point of view about aerial navigation as viewed from the cockpit — about the options thatare open and the options that are not open, about thechanges that are feasible and those that are not.

I view flying airplanes these days, under the positivecontrol system at least, as sort of a partnership operation.Without the skill and manipulation of the pilot, a clearance cannot be followed, and without the clearance, thepilot hasn't got anywhere to go, and I'm informed ratherreliably that in an airplane you can't stop and think itover. The best we con do is a holding pattern, and goinginto one of those unexpectedly is the some as changingcourse without either radar separation or notification toany of the other parties concerned — such as other pilotschanging another course and heading for the same pointat the same time. The traffic controller, I think, must againborrow from the pi lot the not ion of cont inuing proficiency. Now, this is not to soy there is not a system at themoment where proficiency is unnoticed, and hopefully,should it dissipate or disappear below a certain point,cause the controller to be removed. But, we ore sufferingfrom a serious problem of understoffing in most of thehigh-density facilities. Certainly the worst of these oretroubled now with the controllers working mandatoryover-time, and sometimes more than eight hours of theday and sometimes extremely long periods of time at thescope without relief. No psychologist has ever said thatthis is feasible. We have been told that it is not thoughtwise for any pilot to fly more than 25 hours a week — atleast those who do so professionally. If that is so, it seemsthat the equally taxing job, if not in some instances moretaxing job, of Air Traffic Control, by the boards or in thecab or even on ATP, should not run about 2V2 timesthat. But that is the way that things are working now.

Just OS we don't hove back-up systems, we don't haveback-up personnel. I've never seen a cockpit in an airlineryet that did not hove two people that could fly the airplane all by themselves and a third one that might beable to, if it ever came down to the nitty-gritty. But, sometimes we have controllers running two scopes because ofdouble-ups and this is far from healthy. Indeed, I shouldthink that because you can't just change controllers automatically — one has to sit and get the picture (just as Ican't slide into the left seat of the Lear Jet half-waythrough a descent and take over the controls withoutknowing the fix toward which we are heading, the expected approach time, the procedure that we're going to useand the approach plate that is germane to our finalmaneuvers before landing), one controller can't go running from the boards and have another sit in and get thetotal picture. There is a rotation scheme, and in order toallow periods on and off duty I should think it would be

helpful to have something in the nature of a co-pilot, whomight be a trainee, but who at least is available to takeover should the need arise. We occasionally have AirTraffic Controllers that get sick just like everybody else inthe business and, sometimes, they get sick at the worstpossible time, because the sickness ist not entirely unrelated to the crisis which they hove encountered.

Now, how much training and how many years shouldbe token? I think we can project that on a theoreticalbasis, because somebody, I'm sure, con sit down andcreate a reasonable syllabus which involves a phasing inof on-the-job training, just as we begin, in the military atleast, our pilots with a belly-full of ground school and thenfinally let them sit in an airplane and more and more correlate the two until we're really learning to fly. On-the-jobtraining is no substitute for theory and especially thetheory that becomes more and more important as the system becomes more and more mechanized and complex.That theory should be taught formally and completely int h e c l a s s r o o m .

Where ore these controllers going to come from? Whywould anybody wont this job? I think one of my friendswho flies for TWA put it as succinctly as anyone ever haswhen he said one night to a harried controller who obviously had frazzled hair on both sides of his head, "Youknow, I'd rather do my job for your pay than your job formy pay". Well, the disparity there is about 300% on theordinary pay scale. So why should anybody want toundertake this job — it offers very good advancement atthe start and tends to level off.

The skill and ability — including that special quality,"resilience", which I don't think will ever become unnecessary to this profession — requires a special kind ofguy. I think that perhaps in the future, unless the universities undertake, as they do now in many flight courses, toprovide specialized training under some government control in on approved plant (because I don't ever expect theAir Traffic Control system to become competitive withinthe industry; I think we're going to stay with the Federalgovernm.ent as a supervising agency for as long as wehave such a system), unless the universities do that, Ienvision a Federal academy something like the ones thatwe use in each of our military services — where peopleore given training from the ground up and have some kindof commitment; where, at government expense, they aregiven a Bachelor's degree together with a highly specialized body of knowledge that they can use in carryingout the duties for which they ore being trained. If itappears that despite all our efforts to relieve the moment-to-moment burdens and the mental stretching — which isreally what it is — of the Air Traffic Controller, who nowmust maintain in his head so many different figures andsmall, little memories that are constantly shifting as hehands off targets and receives more — if we are unableto do that, it appears that youth is always going to be arequirement of the what is now called "Journeyman Controller" (a term which I might tell you they are trying toshake because Journeyman smacks of a trade and theylike to consider this, and properly so, a profession). But, ifthat is to be a condition that will exist ad infinitum, thensomething has to be done to accommodate these peoplewhen they are no longer in a mental condition — and Imean a combined physical and mental condition, becausemental stress evidences itself, as business executives know,in many physical ways.The least pleasant of these is called

cardiac arrest, and bearing upward on the scale we getto the annoying little things like ulcers. But when theyappear, there is a reason, especially when statisticallythey are out of proportion in the age group involved, andI don't think that simply stretching human being is anyvery satisfactory answer to the system. What are we going to do with them afterwards? The Air Traffic Controllerwho is in his 40's or 50's and either is no longer suited for(if that be the case, then we may well be able to remedythe situation) or no longer desires to, simply because he'dhad enough of that business, ought to be put in some areawhere his special skills are of special value. I don't knowof any present value for Air Traffic Controllers exceptworking for somebody else in the business of Air TrafficControl and the number of openings in that phase of theindustry is certainly limited, both as to the advancementin to execut ive eche lons in the FAA and to those execut ive

position in the airlines that maintain Air Traffic Controlexperts to advise them in their day-to-day recommendations and procedures, training and so forth.

So, these are some of the things I think we're confronted with. I don't think the system can ever be any betterthan the controllers that are in it. Although the controllers,in and of themselves, are never going to be able to pushit up to the point where it needs to go. I've been, I think,startled to some degree and dismayed to some degree,by the fact that we're running uphill and will be for someyears. There is no way to get an academy going overnight. There is no way to get a bunch of trained controllers overnight, and indeed to get a man qualified, evenif he's pretty sharp, to handle peak hour traffic in the NewYork area is going to take several years — not severalw e e k s .

So it seems to me that we ought to be planning ahead.I'd like to take these projections that have been made andregard them as conservative, and figure out how manycontrollers we need today to properly staff the positions,including back-up slots, and then triple it just to be ont h e s a f e s i d e .

I t h i n k t h e r e ' s b e e n a t r e m e n d o u s a m o u n t o f f a l s eeconomy in the business of Air Traffic Control. When Congressmen began to circle the Deer Park Omni, which is aname that has come to be hated by many airline passengers who knew where they were during their three hoursorbiting on Black Friday over New York, the Congressmenthen again began to reconsider the problem. Either because they were sitting in the airplane or because theCaptain was wise enough to invite all of his passengers towrite a letter to their Congressman — indeed furnishing thename, address and the stationery during the hours of orbit.

It may seem that a sense of false economy is what'strapped us after all. As I have indicated — all the pressbegan to look for a "Black Hat". Whom are we going toput the blame on? And that certainly is the wrong approach. I've looked at all the hats available and sometimesunder them in an effort to see if somebody should be giventhe b lame so we cou ld a l l so r t o f "home in " on h im andlet him have it. But I don't think anybody is entitled to theblame. Sure, the Congressional Record reflects that someyears ago the Congress was told: "we need more of thisand more of that and more of that, and we didn't get it",but the Congress is told every year that they need more ofeverything and, from the articulation gone into, there wasno reason for them to suspect that Air Traffic Control wasfar out ahead of the L is t .

However, we have, in my judgment, the finest airplanesthat our technology can provide. They are, in my judgment,very safe machines and I continually demonstrate my credence in that statement by staying aloft about 100 hours amonth. As I said, we have bent over backwards in orderto make sure that when one thing goes out, something elsecomes into play. We've got three ways to lower the landing gear, two for the flaps, a couple of inverters andemergency battery-powered gyros in case all that businessquits, and we have some pretty well-paid people flyingairplanes. We certainly would do well to stop talkingeconomy as the first line, but to talk safety and service asthe first line in Air Traffic Control. Every time we arecircling eighty 700 series Boeings over New York becausethe number of controllers, the amount of radar, and theamount of concrete in the New Yorker area, is simply inadequate to handle them at the rate at which they appearand ask to be let down, we are spending an awful lotmore money than would have been spent if all these facilities were precisely doubled five years ago. If the presentprojections for increases in air traffic should be anywhere near accurate, and I have said I think they are conservative, because the last figures I have seen indicatethat about 20% of living Americans have flown in airplanes — if this is so, I can tell those of you who are slightly beyond it and reassure those of you who ore still in it,that my generation is going to reverse that. By the timeI die I believe that 80% of the people will have flown.And, since I'm not expected to live forever, that is a quadrupling of the present capacity. There is no other way totravel in the United States except by air — unless youhave got a new car and you insist on driving it for 1,000miles — because railroads are no longer even a piece ofthe system and even if they were, business will not permitsomebody to travel at 80 mph — they demand he moveat 500, and there is only one way to do that. This is thetime, in my judgment, to use a bold approach, instead ofa few-new-ways-to-get-along approach, so that we don'twind up in such bad trouble again. It is unfortunate thatthe only remedy for which we can reach at the present timeis restrictions. It may initially help the position of the airlines; it may fill some seats that have been running empty,but, when that buffer runs out, it's going to mean thatpeople who want to fly, that the natural growth of aviationhas been inhibited and that in order to cure the probleminstead of going forward and opening up the skies andmaking better use of each cubic inch of air space, wehave gone backwards and imposed restrictions. Restrictions will solve any problem, I suppose, but they fly in theface of progress.

So, I hope that this is a temporary thing. I hope thatany measures that are adopted have a fixed time limit atwhich they expire. I hope that, because of good foresight,the willingness to spend the dollar as it should be spent

when you re fooling with 8 million dollar airplanes and120 lives in each one — the American public is going tohave a system which is sufficiently progressive and whichhas sufficient foreplanning to accommodate the amountof flying that it wants to do. After all, it was for that publicthat this system was built and I think that there is no wayto justify it, if we say we can't keep up with the system.If the effort is made and the proper education is given tothe proper people, and those, gentlemen, ore the peoplethat got the money!

Thank you very much.

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ATC Automation in the U.S.A.By Ferris J. HowlandActing Deputy Director, Air Traffic Service,Federal Aviat ion Administrat ion,to the 1968 RTCA Annual Assembly

The recent publicity given air traffic delays at severalmajor airports has accentuated many of the problem areasin the realm of flight, particularly those concerned withthe control of air traffic. The air traffic control funct ion ofFAA has suddenly become one of the major culprits in theminds of many for a situation which developed for beyond the vision of either government or industry forecasters. The fact that knowledgeable people were doingthe forecasting has no bearing on the matter since theproblem will not be solved nor will it disappear by fixingthe blame for "who shot John". It would be nice for us inthe FAA to "get off the hook" by saying we have the answer to the delay problem — "automation of the ATCsystem".

We all know automation, which has had a dramaticeffect on our way of life and has had many exotic claimslaid to it, is not the answer. It will change our way oflife in the control of traffic but it will be only as good asw e c a n m a k e i t a s a t o o l f o r t h e c o n t r o l l e r a n d n o tO S h i s r e p l a c e m e n t .

One of our biggest problems in providing automationin the air traffic system has been to determine just exactlywhat functions of an air traffic control facility do we wontto automate. No matter to what use a computer is puttoday, the constantly changing air traffic picture at agiven moment in a given area present difficulties thatstymied development of automation in air traffic controlfor a long time. Intensive research efforts hove been expended by FAA with input from highly competent industrial brainpower to provide automation in the ATC system.Several well intended systems on which,may I add, a greatdeal of money was spent, did not meet the needs. Buteach failure taught us something.

One thing we learned was that not all the functionsperformed within on air traffic control facility need to beautomated, nor is i t desirable.

It is easy to overlook the fact that no matter what wedo to help the controller — giving him black boxes andsophisticated displays — the end product of providingseparation to two or more airplanes is his capability tomake a decision. Poise, skill, and professionalism do nothove a price tog. There is no doubt in my mind that ifautomation of the air traffic control system ever reachesthe stage where all traffic is controlled by pushing a redor green button, it will have reached that stage becauseof the poise, skill, and professionalism of our air trafficcontroller complement today.

We must assure that research does not overlook thefact that the controller is on effective 180-pound computerand has the advantage of often being produced at lowcost by unskilled labor.

What, then, do we intend as the goal for ATC automation and where are we today in meeting that goal?

Our program is based on the recommendations of agroup of consultants appointed by President Kennedy in1961. This group, called the Beacon Task Force, was commissioned to study the air traffic control system, and torecommend what, if anything, should be done to improvei t . T h e i r r e c o m m e n d a t i o n s w e r e a s f o l l o w s :

1. The primary source of real time data should be thealready existing network of primary radar, supplemented by a cooperative air / ground air traffic controlradar beacon system capable of providing discreteidentity and altitude information in increments of 100feet. In this regard, the task force strongly recommended that industry be encouraged to produce equipmentwithin the price range of the small aircraft operator.

2. Give the air traffic controller the best possible displayof the air situation for which he is responsible — bestpossible in terms of ease of interpretation, clarity ofpresentation, etc. This display should include electronically written alphanumeric tags of the discrete identityand al t i tude of each aircraft with which he is concerned,and perhaps additional information where required,such OS ground speed as an aid to final approach spacing in the terminal area.

3. To the maximum extent possible, minimize the workload involved in the non-decision making processes.Such tasks as maintaining location and identity, initiating or accepting a handoff of control, and the entering, printing, and updating of flight plan information.In our development work since 1961, we have followed

the guidelines of the Beacon Task Force. We are nowrapidly approaching the time when the program emphasiswill shift from development to implementation.

For several years, a semiautomated terminal systemhas been in operation at the Atlanta, Georgia, Tower. Thisis a prototype system known as ARTS, for "automatedradar terminal system". It is to be followed in the springof 1969 by the commissioning of a similar installation nowin test and training status in the New York Common IFRRoom at the Kennedy Airport.

Among the functions performed by these systems is thealphanumeric tagging of aircraft with identity, groundspeed, beacon code and assigned altitude. The actualaltitude and its changes can be also displayed in onehundred foot increments for aircraft equipped with beacontransponders having Mode C altitude capability. Of equalimportance is that the tag will track with the aircraft target. The system also has the capability of providing automatic intra-facility handofFs between positions of operat i o n .

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We do not intend to stop the terminal automation program with these two facilities. Based on laboratory studiesand a successful field trial, we have developed a modularautomation system to provide capability to terminal ATCfacilities in logical steps according to specific needs.

Let's review the modular or building block concept. Thisconcept is one under which we can tailor to a terminal'sspecific need and which can be expanded as traffic increases. Work has continued in this program with a decision to implement the beacon tracking function at thebusiest terminals. Technical specifications for the systemand expansion steps were published in January of thisyear. Proposals from industry have been received and arecurrently being evaluated.

The plan is to install the beacon tracking system, whichwe have called ARTS III, at the major and medium activityterminals. As stated earlier, Atlanta and the Nev/ YorkCommon IFR Room are already equipped with systems ofthe original field evaluation hardware. These systems areknown as ARTS I. It is the agency's desire to eventuallytake advantage of radar beacon altitude data from equipped aircraft at all of our radar facilities.

There may be a question in your minds as to why weaimed our initial effort at the major and medium terminals. The answer is obvious. In 1967, over 70 percent of allinstrument operations and 80 percent of passenger en-planements occurred in the major and medium terminals.

Much of the foregoing concerns the ''where'', and "whythe where". Let me now point out the "what".

First, let us picture a typical radar display as seen bya controller at one of our busier terminals — ChicagoO'Hare. On the 60-mile radar display at O'Hare, there areapproximately 300 radar targets during traffic peaks. Thisnumber is predicted to exceed over 600 by 1976. It iseasy to visualize that with this number of targets, the con=troller has difficulty in maintaining identity, altitude andspeed information.

What will the ARTS III beacon tracking system do forthis display? It adds the following items which have provenvery valuable aids to the controller in our Atlanta experience:1. Alphanumerics on all beacon equipped aircraft.2. Alphanumeric ground speed on all beacon equipped

a i r c r a f t .3. Altitude readout on Mode C transponder equipped air

c r a f t .4. Display enhancement through use of the beacon track

ing function and altitude filtering.5. Additional items of information to assist the controller.

I believe we can all recognize these as improvements.Now, what makes it go? Simply stated, to our present

radar (pnmary and secondary) we add an acquisition subsystem which converts the secondary radar or beaconvideo into messages which can be fed into a digital dataprocessor. The processor combines these data with otherdata instructions obtained from its own stored program,from messages entered by the controller, and messagesfrom the center computer, and presents the results asalphanumeric data which it adds to the regular radardisplay currently used by the controller.

The previous discussion is a simple explanation of howthe system works for the initial implementation level. Thenext expansion would involve going to a full digitalsystem in order to mosaic or combine several radars fordisplay of significant data.

Thus far I have spoken only of efforts toward automat ion o f the termina l cont ro l funct ions o f the a i rtraffic control system. Efforts on automating the e nroute functions actually precede terminal efforts. Although we have not yet commissioned an automated center, the National Airspace System Stage A En Route Program is in a stage of development which will provideflight data processing in the Jacksonville Center by Calendar Year 1969. The existing flight plan processing beingperformed in centers is a mixture of manual processingand semiautomatic processing in those facilities that arecomputer equipped.

Development of an en route computer system began in1957. The early systems proved very valuable but as trafficincreased they reached saturation on busy days. Based onthese experiences and the advances made in computertechnology, it was decided to design a modular system thatwould fit the amount of traffic handled by each center andcould be added to as needed.

The results of this plan will be a system that operates24 hours a day and seven days a week with a "fail safe"capability to keep disruption of the ATC system to a barem i n i m u m .

Our implementation plan for the en route centers is tointroduce automation in two major steps. In the first step,the computer, because of its early availability, will beused to process and distribute flight plan information, thusrelieving our controllers of an increasingly heavy clericaland bookkeeping workload. In the second step, the alphanumeric tags will be added to the controllers' displays.Generally, the flight plan processing capability will precede alphanumerics by one to two years at each center.

In addition to providing an on-line network of computers between facilities, these systems will overcome thefollowing limitations in the existing system:1. The slow and cumbersome manual processing and dis

tribution of flight progress strips.2. Capacity of the current computer and cardatype units

which is frequently exceeded.3. The error potential in human preparation and handling

of flight progress data.4. The excessive and time-consuming telephone coordina

tion required for the manual exchange of flight planinformation between adjacent control sectors and facil i t i e s .

We anticipate that the introduction of the automatedcapabilities of the NAS will contribute much to aviation byincreasing the efficiency of the air traffic control serviceand by eliminating some of the delays in aircraft movements which are encountered by communications andmanual processing of data for the control of air traffic.Automation in this system will process data in microseconds and display it in a usable form to the controllerin fractions of seconds.

Along with the display of Mode C altitude information,the rapid and accurate processing of data providing thecontroller a real time display of conditions will permit himto devote more time to decision making and will assist inrelieving one of our biggest problem areas, frequency congestion. The schedule for en route automation for all FAAcenters colls for completion by the end of 1973.

I have no wish to bore you with numbers, but a fewsimple statistics will help to illustrate the significance ofthe automation programs I have been talking about.

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During Calendar Year 1967, the 27 air route traffic control centers operated by the FAA handled in excess of 16V2 mill ion IFR aircraft. Five of these centers uti l ized com

puters in the preparation of flight progress strips requiredfor each aircraft, but a large percentage were preparedmanually. Based on a reasonable assumption that a national average of five strips per aircraft were required, over82 million actions were needed just on the basic need toget information to the controller. These figures do not include the quantity of controller manual actions requiredto update the information on each strip, nor do they reflect the number of communications contacts required tocontro l the t raffic.

If you think those figures are impressive, let's look tothe future. In Fiscal Year 1974, less than five years hence,the IFR aircraft operations handled by centers are forecast to total 31.8 million; by Fiscal Year 1979, 44.9 million.

In Calendar Year 1967, IFR operations at airports whereagency control towers were operated totaled slightly over11.6 million. Contrary to the centers' multiple sector needsfor duplicated information, the foregoing figures can beprojected on a 1X1 basis rather than 1X5.

Again looking to the future, in Fiscal Year 1974, terminal IFR operations at FAA tower locations are forecastto be 27.8 million, and in Fiscal Year 1979, 41.7 million. Asin the cose of the center statistics, these figures do notreflect manual updating and communications requirements.

Historically, forecasts in the aviation business hovebeen conservative; but at least the figures I have cited arerelative and indicate a continued increasing operationalgrowth. As a final statistic, you may be interested in learn

ing that the Nation's air fleet is growing at a rate of 13new commercial jets every 10 days and 20 new privateaircraft every day.

It is easy to visualize that the sheer weight of manualmanipulations required to keep pace with these quantitiesof operations will swamp the controller with clerical andbookkeeping chores. It is, therefore, obvious that some ofour air traffic service functions must be automated. This isbeing accomplished. It will be evolutionary because thereare factors involved which must always be considered firstorder. One is safety which will not be compromised. Thesecond is compatibility across the user spectrum, alongwith the capability of controller personnel and equipmentto advance wi th user demands.

The ATC problems ore often common with engineeringproblems in that they consist of two parts:a) the job that has to be done; andb) the effects which do not interfere with the set purpose

but which must be token into considerat ion.Economics is often a governing factor, nor can we overlook other needs of the ATC system while concentratingon automation. For instance, improved navigation andapproach aids must be complemented by improvements intraffic handling.

We would wager that given a volume of aircraft, today's air traffic control system con swamp any airport inthe country. It must be remembered that automation of theATC system is not a total remedy for the delay and congestion problem. This problem must be attacked from airport to airport and all those parts of the system that arein between.

ARTS In-Service ImprovementsBy J. Milton HatchellAutomation Coordinator, Atlanta, U.S.A.

In the beginning R&D created ARTS, a creation whichcontinues to impress me as much today as it did in thebeginning. Functionally it is the best-planned new ideathat I have seen. Granted it is more sophisticated nowthan when originally installed. However, none of its original program has been removed, but merely improved andexpanded.

ARTS was designed originally as a test unit to answerthe question, "will alphanumeric data and automaticallyreported altitudes help the terminal controller"? It was

intended to test this in Atlanta and then return the equipment to Atlantic City. The potential of this new conceptwas soon recognized, however, and it was decided toleave ARTS in Atlanta for further testing and improvem e n t .

Many problems came with this new electronic assistant.It had to be told everything by the controller, through thekeyboard. It was supposed to keep its tag with the correctaircraft target, but when another target crossed the pathof the one it was tracking, it frequently became confused

15

and followed the wrong aircraft. Occasionally, its togsbecame overlapped each other and then neither would bereadable. Controllers also were faced with the problemsof getting used to the alphanumeric clutter, as well as anew type of display — the scan-converted RBDE-5.

The automation coordinators, who are radar controllers trained to be programmers, are able to recognize andunderstand the controller's problem and also determinewhat must be done to correct any program difficulty. Sofar we have not been able to come up with all the answers, but are making progress.

The alphanumeric data tag may be offset at any one ofeight positions with respect to the target being tracked.If the tags of two aircraft overlapped it was necessary forthe controller to give the computer a new offset locationfor one of the tags. This required six manual keyboardoperations entering a two-digit track reference number,depressing a category button, a function button, enteringa new single-digit offset location and then depressing theentry button. This was one of the first things we simplified.An addition was made to the computer program to checkeach console (scope), in sequence, and every tag on eachindividual console, for an overlap condition. Now, whenan overlap exists, the computer determines in which direction the tag may be relocated without an overlap, andpromptly resets it to this position.

Originally, each tag had to be referenced by its tracknumber and the controller was forced to type in this two-digit number, preceding any communication with the computer. The computer was given the additional capabilityof finding this track number when the controller placedhis "slew dot" on the tag that he intended to change. Theslew dot is a visual electronic indication controlled by atrack ball unit or "slewball" mounted in the console desk.With this device the controller can place the dot on aradar target and when he depresses the enter button hesends the computer both range and azimuth information.Positioning the slew dot is a much easier method of designating a target, than typing in the track number. Inaddition, the alphanumeric clutter can be reduced, by inhibiting the track number from the display.

Each display has a store area and a hold area. Theseare tabular display areas where data tags are held in aninactive status. Our next innovation was to let the computer move a tag having a discrete transponder codeassignment, from this store area onto the aircraft targetsquawking that code.This automatic tagging feature allowsus to pre-record on magnetic tape the flight numbers andassigned beacon codes for all scheduled flights in and outof Atlanta. By another addition to the programming, thecomputer is able to read this tape and automatically storethese data tags at the appropriate consoles.

The arrival and departure flights are arranged by time.Code assignments are made within each code group beginning with code 12 progressing in sequence to 77 andbeginning the cycle again at 12. Arrival codes 0212 through0277 and 0412 through 0477 are used. Codes 0201 through0211 and 0401 through 0411 are left for random assignment by the arrival handoff controllers.The departure codegroups 1000 and 2000 are handled in the same manner.

During the period in which the automatic tagging feature was being developed, an automatic track terminationcheck was being added. The tracks of the terminal anddeparture controllers are automatically cancelled whenthe aircraft reaches a range of twenty-five miles from the

radar antenna. The tracks of the approach controllers areautomatically terminated when the aircraft is on finalapproach and within four miles of the runway. The computer is programmed to automatically initiate a handofffrom the feeder controller to the pattern controller whenthe aircraft enters a prescribed area for the landing runway in use.

The question was asked, "would ground speed help thecontroller?" and the answer was "yes". Ground speed isnow computed from successive aircraft positions. It isdisplayed automatically to assist the controller in settingup and maintaining optimum approach intervals.

Keeping the tag associated with the proper target isstill a major problem. To track a specific aircraft, the computer needs to know whether it should search for a beaconcode, or should track from the primary radar reports. Timedoes not permit the controller to enter this informationduring peak periods, so the tracking program has beengiven the capability to make this decision automatically.However, if an aircraft is squawking a non-discrete code,such as 0400, the computer must revert to the primaryradar data, to track the target. This presents even moreheadaches, because tracking from primary radar dataalone is very difficult as the tracker frequently switchesidentity to the wrong aircraft. We cannot get along without radar tracking, at this stage, however, as a considerable percentage of our traffic is made up of single-engineaircraft and light twins which are not equipped with 4096-code transponders.

The tracking computer program was modified to accomplish discrete tracking. This allows correlation withonly that code which matches the assigned code of a particular tog. Even this tracking method relies on radar reportsas a backup, but if the matching code disappears for foursuccessive antenna scans, the tag is removed from onactive status on the scope and placed in the hold area.The computer continues to search for the matching beaconreport, and when it is found the tag is replaced on thetarget and tracking is resumed.

ARTS does its best job when all aircraft under controlhave 4096 identity code-transponders with automatic altitude reporting; but until that day arrives, remember thatmany light aircraft are also flying in our airspace withoutthis sophisticated equipment, and their safety is just asimportant to us as the safety of anyone else.

By modifying and adding to the computer program,we have been able to rel ieve the control ler of about 60%of the manipulation workload that was required initially;64% of our scheduled airline flights now have the 4096-code transponders.The alphanumeric data for these flightsrequire no controller action except issuing the propercode assignment to the pilot. The data is stored automatically. When the computer receives the matching codeit places the data tag on the target, and tracks it acrossthe scope. If during this process it encounters an overlapcondition it will relocate the tag; if it loses the matchingcode it will remove the tag, and reposition it on the targetwhen the matching code is found. Finally, when the flightreaches the prescribed point of termination, it will terminate the tag.

ARTS is an intelligent little gentleman who has movedfrom kindergarten into his elementary education. He willcontinue on into his higher education phases but he willnever graduate, because there will always be controllersteaching him new things and new techniques.

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Area NavigationBy Robert W. MartinChief, ATC Operations and Procedures Division,Air Traffic Service,Federal Aviat ion Administrat ion,to the 1968 RICA Anna! Assembly

I n t r o d u c t i o n

Throughout the history of aviation, one basic problemhas plagued planners and users of our national airspace.That problem is how to provide sufficient usable airspaceto accommodate the ever-increasing user demands.

The evolution of navigational aids dramatizes thisquest for more and more usable airspace. Homing beaconsgave way to low-frequency ranges because more accuratepositioning allowed more aircraft to be safely separated.VHP omni-range (VOR) stations have replaced low-frequency ranges and opened more airspace by providingmore routes, reliability and accuracy. The addition of distance measuring equipment (DME) to the VHP system hasprovided additional flexibility and position fixing accuracy.

Despite the improvements represented by the presentVHP airway system over the old low-frequency system,there ore st i l l ser ious l imitat ions which must be overcomeif we ore to meet the forecasted demand on the ATC system. The main limitation is the fact that the present navigational methods result in routes or airways which areeither directly toward or away from the station. This creates a convergence or tunneling of air traffic and resultsin a severe limitation on the configuration and the numberof routes available between two points.

The same deficiency takes on even more importancewhen you consider that arrival and departure proceduresare based, in large measure, on the same ground stationsas our en route structure. This means the tunneling effectis compounded by altitude changes for transitioning traffic. That is, the constantly changing altitudes of arrivingand departing aircraft make the controller's job moredi fficu l t than in the en rou te env i ronment where a l t i tudechanges are less frequent.

The next logical step towards providing more airspaceand reducing traffic congestion is the development of anavigational capability that permits accurate route definition on an area basis without the constraints of site location or course alignment.This capability is commonly termed "area navigation" which could be defned as navigation not confined to flying a radial or track toward oraway from the ground station providing the navigationalguidance.

At present, the form of area navigation most commonly used is the application of air traffic control radar. Thistool, in the hands of the controller, has opened up a greatdeal of airspace and provided great flexibility. However,this has been accomplished at a tremendous cost in termsof controller workload and equipment requirements.

A point of diminishing returns has been reached in theuse of radar for area navigation. As the demand for radar

vectoring service increases, the number of aircraft a controller can safely handle decreases because of increasedworkload per aircraft. More and more of the controllers'time is consumed in navigational guidance; leaving lesstime for the vital function of separating aircraft.

Background on Area NavigationSeveral airborne systems have been developed which

put area navigation capability and responsibility in thecockpit, where it rightly belongs. Among these are courseline computer, pictorial displays, doppler radars and in-ertial platforms.

The mere fact that these systems can furnish navigational guidance from one geographical point to anotherdoes not ensure their operational suitability in the airtraffic control system. Several other factors must be considered. First, system accuracy must be established. Wemust be assured that protection of the intended route offlight of an aircraft does, in fact, protect the aircraft fromother a i r c ra f t .

Next, area navigation systems must be procedurallycompatible with other systems currently in use. At somefuture date, area navigation capability will probably dominate; but in the interim, the air traffic control system mustaccommodate both area and conventional navigation systems in the same airspace.

Another consideration is cost to the user and to theGovernment. The user must be assured that his expenditure will buy him improved safety and service. The FederalAviation Administration must be assured that the bestpossible service and the greatest safety is provided at theleast possible cost.

Another major consideration is compatibility with FAAplans for the National Airspace System. Acceptance ofnavigation systems which cannot be accomodated in theplanned automated environment would impose an impossible load on our traffic control facilities.

The azimuth and distance information generated bythe present VOR-DME system when processed by an airborne computer con be used as the basis of an area navigation system. It has the advantage of being a systemwhich is presently in place and can be used by aircraftequipped with the present rho theta navigational equipment as well as those equipped with area navigationcapability.

With these factors in mind, we con develop concepts ofuse, within the air traffic control system, that will enhance

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the controller's abil ity to cope with the ever-increasingtraffic volume through better use of the available airspace.

Operational Concepts of Area NavigationWe, in the Air Traffic Service, must emphasize that our

primary objective, in applying area navigation capabilities, is not to free pilots from airway flying and permitthem to fly randomly where and when they please. In anytraffic situation where volume is a factor, regimentation isnecessary to provide separation by a ground-based system. However, area navigation techniques hold promiseof improvement for both pilots and controllers in all phasesof flight activity. To illustrate this, let's look at some of thepossible applications.

The most immediate possibility is the establishment ofarea navigation airways. These airways will probably becharted and flight checked in much the same manner asour existing victor and jet routes. Parallel and one-wayroutes can be established to reduce the congestion on ourheavily traveled airways. En route traffic can be routedclear of congested terminal areas. Multiple parallel routesmay be established between major terminals to permitsegregation by aircraft speed and/or arrival airport. Eachof these parallel routes could transition directly to theapproach aids without converging at some primary navigation aid. Even in areas where congestion is not a problem, routes can be established along the shortest andmost convenient paths without regard for the constraintsof navigation aid location. Many of the present dog legscould be eliminated.

By the same token, site selection for initial placementor relocation of navigation aids can be based on accessibility, favorable terrain and least iaterference instead ofthe more limited objective of meeting one or more procedural requirements.

Terminal area applications promise to be as beneficialas those for en route operations. Here too, the initialeffort will probably be to establish published and flightchecked routes as opposed to random routes. Departureroutes can be designed to proceed directly from the runway to the appropriate parallel airway without radar vectoring or passing over primary navigation aids. Paralleldeparture routes can be established to alleviate speeddifferential problems.

Arrival routes can be designed to transition trafficdirectly from en route airways to arrival routes withoutproceeding over on approach NAVAID or requiring radarvectors. Instrument approach procedures can be shortened,because area navigation provides continuous position information to the pilot and does away with the need to flyover the station and solve time/distance problems.

Instrument approach procedures con be established formany air ports that do not hove approach NAVAlDs. Thishas not been possible in the post because these airportsh o v e i n s u f fi c i e n t t r a f fi c t o w a r r a n t t i r e c o s t o f N AVA I Dinstallation and maintenance. Now, they can be served byarea navigation approaches based on nearby NAVAlDs.Of course, the minima for these approaches cannot be aslow OS those based on precision aids, such as ILS, but theywill be a significant improvement over the service available to these airports today.

By lifting the constraints of NAVAID location, betternoise abatement procedures can be defined. Shorter ap

proach procedures will mean less low altitude flying timeand a proportionate decrease in noise problems.

Holding patterns, in our terminal areas, can be moreefficiently placed and more accurately flown. They toohave been dependent, in the past, on NAVAID locationand course alignment. V/ith area navigation they can bealigned for expeditious transition to approach routes.

Thus far, we have talked only about predefined andpublished applications for area navigation. Another veryimportant facet of this system is its flexibility of choice inselection of routing. This is seen as a useful tool for thecontrollers. Let's look first at this capability as a supplement to radar control. Under our present system, if off-course vectors are required for separation of oppositedirection or in-trail aircraft, course guidance must be provided unt i l the a i rcraf t is back on his c leared route. Witharea navigation, this same type situation could be greatlysimplified by instructing the pilot to fly a parallel coursefive miles right or left. The controller simply monitors hisradar display to ensure adherence to radar separationstandards. All course guidance remains in the cockpit, resulting in a reduction of both verbiage and chances ofpilot disorientation.

More flexible routing capability will greatly reduceradar vectoring requirements for weather avoidance. Today, a radar controller frequently finds himself vectoringvirtually all aircraft under his control due to severe weather areas. With area navigation capability, a single clearance to each aircraft could provide complete routingthrough the trouble area. The controller can now devoteless of his time to navigating and more to his primary dutyof separating aircraft.

Where we are TodayDevelopment and implementation of such a system is

not an easy task; nor should this system be construed tobe a panacea of all the ills that plague the air traffic control system.

Many problems remain to be solved. Several projects,in cooperation with private industry, are underway to findsolutions to these problems and explore ways of developing the full potential of the system.

Currently in progress is an airline evaluation called the"Northeast Corridor Project". Airline pilots are employingarea navigation equipment and techniques on regularlyscheduled flights. These flights are, of course, provided thesafeguards of ATC radar monitoring as well as havingconventional VOR/DME capabilities in the aircraft. Thepurpose of this evaluation is to examine the feasibility ofusing area navigation in an operational environment.

This project is limited to examination of only the enr o u t e e n v i r o n m e n t s i n c e t r a f fi c d e n s i t i e s i n o u r N o r t heastern terminals seldom permit the handling of specialflights, that do not conform to general traffic flow. Evenin the en route environment, heavy traffic often forcesthese evaluation flights to remain on conventional routes.This is unfortunate, but it does serve to emphasize theimportance of careful procedure development. We mustdevelop not only full-scale area navigation procedures butwe must also provide for the ever changing ratio of equipped to nonequipped aircraft.

The "Northeast Corridor" project is providing valuabledata to the airlines and equipment manufacturers, as wellas the FAA. The airlines are able to develop pilot proce-

1 8

dures and techniques while seeing for themselves the advantages to be realized from such a system.

The equipment manufacturers are provided the bestpossible test-bed for their products. By seeing their equipment used in an operational environment, they are betterable to anticipate what will be expected by the users.Several recommended equipment design changes have already been incorporated as a result of this project.

Another airline evaluation is in progress using areanavigation routes between Chicago and New York. It isproposed that eventually these routes be extended to theWest Coast to be used by transcontinental flights. Thiswould provide a good look at the system under a broadrange of conditions.

Another evaluation is underway by the Flight Standards Service of the FAA. Area navigation equipment hasbeen installed in FAA aircraft to provide a test-bed thatis not limited to scheduled times and routes. These flightsare designed to include a very broad range of operations.The objectives are to determine potential application,technical standards, and system accuracy.

The findings from all the evaluations will be the basison which the FAA will develop separation standards, weather minimums, equipment standards, and operating procedures for pilots and controllers.

Where do we go from hereIntroduction of area navigation into the air traffic con

trol system will, as you might except, have far reachingeffects on future planning of airspace utilization.

We need the answers to some very important quest i o n s :

— Is this system good enough to commit our nationalplanning in this direction?— Is this system economically feasible for the aviationindustry?

— Can we safely implement this system?

In attempting to answer these questions, we must lookfar into the future and attempt to anticipate every possibleimpact of this system.

One such look into the future is a simulation to be conducted in the air traffic control laboratory of the NationalAviation Facilities Experimental Center (NAFEC) in Atlantic City, New Jersey. This simulation is to be based on theNew York terminal area including the satellite airports

and will be predicated on area navigation as the primarysystem in use by the flying public. Twenty percent of thesimulated traffic will not be so equipped, however, toprovide a look at the ATC system's ability to accommodate special cases.

This simulation is expected to provide us with insightinto future airport design considerations, NAVAID placement, route alignment and desirable airborne equipmentcapabilities.

Future study groups will have to consider many otherquestions, such as flight inspection requirements. Today,our flight inspections concentrate on published procedureswhich are based on specific radiols and courses of ourNAVAIDs. Safe altitudes are based on course guidancereliability and terrain clearance along these specific routes.Area navigation will use all of these courses and radials.We need to develop feasible methods of determining minimum reception and terrain clearance altitudes for theentire service volume of these facilities. Then we must develop the best methods of notifying the flying public ofthese min ima.

Assuming for a moment, that the answers to all thetechnical questions can be found, we must also assureourselves that we are not proceeding in conflict with plansto which we ore already committed. National implementation of the NAS Stage A computer system is already wellunderway. We must develop a means of accommodatingarea navigation flight plans in this automated environment. For example, route definition techniques must bedeveloped that permit the controller to communicate themto the computer in a timely and accurate manner. Randomrouting can be expected to complicate this problem considerably.

C o n c l u s i o n

Area navigation, though not the answer to all our problems, does promise to be a significant step toward betterservice to the flying public.

Only a few of the problems and plans have been mentioned to illustrate the work yet to be done. No matterhow desirable this system seems or the advantages itappears to offer, it cannot be implemented overnight.

Through the continued cooperation of private industryand the FAA, we will, in the not too distant future, havethe answers to these questions and open the way to bigger and better things in our vital aviation industry.

I n t h e n e x t I s s u e

Among the contributions to the next issue of THE CONTROLLER will be the following interesting articles:Air Traffic Control in the U.S.S.R,

Impressions from a study tour of Soviet ATC facilities; with many exclusive pictures.Automatic En-route ATC displays

An interesting proposal by a working controller for the improvement of present-day ATC displays.

Falconry in the Air Command of the Royal NavyThe succesful battle of the U.K. RN Air Station Lossiemouth against the hazard of bird strikes.

Management Factors in ATCS StressH o w h u m a n f a c t o r s a r e a f f e c t i n g t h e A i r T r a f fi c C o n t r o l S y s t e m . E d .

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Collision Avoidance SystemsBy Frank C. WhiteManager-Communications and Data Processing,Air Transport Association of America,before the 1968 RICA Assembly

The two most frequently asked questions about airborne collision avoidance systems are:

1. Why do they need cooperative devices in other airc r a f t ?

2. Why must they be so complicated?The purpose of this paper is to answer these two ques

tions and to give you a brief status report on the industrycollision avoidance system development program.

PWI - CASy Functions performedThe scheduled airlines have been working on airborne

collision avoidance system development since 1955 andRTCA has been working on CAS since 1957 — more thana decade. An early step in this effort was the division ofthe possible airborne equipment solutions into PWI (PilotWarning Indicators) and CAS (Collision Avoidance System) ca tegor ies .

The PWI is intended to alert the pilot to the presenceof other aircraft within visual range and advise him of thedirection to look. A PWI might even employ filtering andclassification techniques to permit displaying only themost threatening intruders, but there is one importantthing to remember: a PWI requires that the pilotlook outside the aircraft, fnd the intruder, determine ifit is a threat, and then select and make the appropriateavoiding maneuver.

The CAS provides more functions than the PWI: it detects, sort, classifies and advises the pilot whata v o i d i n g m a n e u v e r t o m a k e . T h i s l a s t f u n ction is the real operational difference between a PWI andCAS: it is what permits the CAS to work in both IFR andVFR weather; while PWI is limited to VFR. Let me summarize by saying that if you are ever in doubt as towhether "this" or "that" proposal for an airborne collisionavoidance device is a PWI or a CAS, ask yourself thisquestion: "Will the device advise the pilot the correctavoiding maneuver to take and not require him to visuallyloca te the a i rc ra f t in o rder to avo id i t? " I f the answer i s

yes — it is a CAS. If the answer is n o — the proposali s a P W I .

Someone might want to haggle with you a bit if theairborne device proposed has a PPI display of all the aircraft around your aircraft and he claims that his device isa "hybrid PWI-CAS". He might say, "My device displays

all the targets and the pilot selects the avoiding maneuver". No one has ever come close to proving that a PPIdisplay in the cockpit will provide suitable information topermit it to provide the CAS function in a congested terminal area. A traffic controller can use a PPI to preventaircraft from colliding, but a pilot, with only his ownaircraft under his control, would be wildly dodging aroundin the sky to avoid all the nearby targets which "looked"like threats on the airborne PPI, but were not threats ata l l .

May I urge anyone interested in building a PWI ora CAS to look carefully at the operational functions to beperformed. Before you start "banging metal" or "soldering" — ask yourself the questions — "What functions willthe finished system perform?" and "Of what value arethese functions?" For example, one agency has a "cute"technique for detecting range rate with cooperative airborne systems — therefore, a PWI! Life isn't quite thissimple. The ability to detect whether two aircraft are closing or opening — and the rate of such closure is realin te res t ing , bu t i t i s on ly a sma l l pa r t o f aPWI's funct ion.

The point is that the pilot must look around and find theintruding aircraft. The "rate" detector tells him to look,perhaps more carefully — but tells him nothing aboutwhere to look. Tests of PWI devices that have beenconducted clearly show that a PWI, to be really effective,should advise a pilot where to look — both in relativebearing and elevation. The "rate" information would helpsome in sorting out the uninteresting targets, but of itself, "rate" would be of somewhat limited value as thesole basis of a PWI.

Why must CAS be cooperative?The airborne collision avoidance system must be co

operative because aircraft fly routinely with 500 ft. verticalseparation (VFR) or with 1000 ft. vertical separation (IFR).It is impossible (and will likely remain so for our lifetime),for any device that does not receive information on thealtitude of other potential threatening aircraft to be ableto resolve whether or not such other aircraft constitute avalid collision threat to the equipped aircraft and to doit in time to permit making an avoiding maneuver.

This statement assumes we start with the idea that wewant to solve the problem — not just a "little piece" of theproblem. If we could be concerned o n I y about aircraft

2 0

that ore closing slowly and could wait until this portion ofthe total family of threatening aircraft were nearby andthen resolve the vertical separation problem, a self-sufficient (non-cooperative, if you prefer a different definition)CAS could be built. Unfortunately, God has not made upHis world in this way and aircraft d o close rapidly, andeven below 10,000 ft. (where the 250 knot speed ruleapplies) it appears that a self-sufficient CAS equipmentwill for some time remain 'Uust beyond reach''.

Why must the cooperative CAS beso complicated?

The relative complexity of a cooperative CAS derivesfrom the numbers of aircraft involved and the largevolume of communications that must be exchanged amongthose aircraft involved in the collision avoidance process.Four factors influence this complexity: the number of aircraft, the number of operations in a major terminal area,the frequency of communications and the techniques thatare available to exchange communications.

1 . N u m b e r o f A i r c r a f t

We all know that it will take from 5 years to a decadefor any airborne device, including a CAS, to be installedin the majority of aircraft that fly in the skies. Airlines,certain military aircraft, certain general aviation aircraft,and other specific ''high utility" aircraft could be equippedin as little as 2 years. Thus in seeking a suitable airborneCAS, we must plan in terms of the aircraft populationthat is expected in the future. Currently there are some2,200 airline aircraft, 100,000 general aviation aircraft andabout 10,000 military aircraft. By the early 1970s the airline fleet might increase to about 2,500 aircraft, but bythat time general aviation is expected to have about150,000 aircraft! If we had the responsibility to plan onlyfor handling CAS communications among the few air carrier aircraft involved, the problem would be infinitely moresimple than having to plan for handling potentially allaircraft. Since an acceptable CAS must be capable ofhandling a I I aircraft, it should be planned on the basisof a volume approaching 125,000 or more participatingaircraft. The capability to handle a large volume of aircraft must be a part of the design or all too soon the CASsystem will become inadequate.

2. Number of Operations In a Major Terminal Area

Currently the number of operations in peak hours atlarge terminal areas is a high as 150 air carrier and 2,000general aviation operations. FAA data shows that by lateseventies to early 80s, the numbers will be as large as350 to 400 air carrier operations and 5,000 to 8,000 generalaviation operations! The figures at nearly every terminalshow that general aviation operations will be more thanan order of magnitude larger than air carrier operations.Thus, it is apparent that if we are to plan conservatively,we must think in terms of a CAS system capable of handling volumes in as large as 5,000 to 8,000 aircraft in amajor terminal area.

3. Frequency of Communications

If you had your "druthers", it would be advantageousfor each aircraft to hove complete data from allother nearby aircraft every instant of time. Thisis because at any instant of time, any aircraft may initiatea maneuver and thereby make previous data of verylimited value. From a practical standpoint, the CAS systemdesigner usually is willing to accept about three secondsof delay as a maximum figure. This means that each aircraft CAS system will receive complete data from eachother cooperating aircraft every three seconds.

4. Techniques available to exchange the Communications

A CAS must exchange all the necessary communications among all aircraft that are close enough to constitutea threat. Typical data that is required includes range,range rate, altitude, altitude rate and velocity vectors. Thefollowing techniques ore possible candidates for providing these data.

a ) I n t e r r o g a t o r - R e s p o n d e rThe most obvious communications technique for ex

changing data among the aircraft is the interrogator-responder technique, each aircraft interrogates and allother aircraft respond. Let's look at some numbers. If 10aircraft are involved, the number of replies is 90 (10 times9). With 1,000 aircraft in a terminal area, the number ofreplies becomes 999,000 (1,000 times 999).

Using the numbers just established dictates that eachthree seconds from 5,000 to 8,000 aircraft must exchangeall the necessary data. Using the lesser of these twofigures, aircraft will need to receive nearly 25 million replies every 3 seconds — utterly impossible using inter-rogator-responder technology.

b) One-Way Ground Bounce RangingThis is a technique invented by Dr. J. S. Morrell of

Bendix Radio in the late fifties. It uses a one-way transmission (which includes altitude data) made each 3 seconds. It measures the direct and ground reflected signalpaths to obtain range. Although this technique will handlewell over 2,000 aircraft, its principle shortcoming is thatthe range data is reasonably "noisy". If range rate isdesired, the range and derive range rate data must besmoothed over 15 to 20 seconds to obtain a reasonablefit of the received data. The one-way ground bounce ranging technique fails by the criterion of exchanging all dataevery 3 seconds and thus, it is ruled out as having muchuseful application in terminal areas. For enroute flightoperations (where maneuvering is much less frequent) itwould probably be adequate.

c) Time-FrequencyAircraft using this system carry an accurate time re

ference derived from a highly stable oscillator. The timereference is used to control the periods (called "slots")within a fixed transmission cycle during which each aircraft transmits complete collision avoidance signals. Thetransmission cycle used by the "industry" system is 3

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seconds with each slot 1,500 microseconds in length. Eachaircraft utilizes a slot and transmits at a precise time within the slot. When a signal is radiated, all other aircraft"listen out". Thus, each aircraft can determine its distancefrom the transmitting aircraft by measuring the one-waypropagation time of the signals. The rate of change ofseparation of aircraft can be determined by measuringthe Doppler shift of the carrier frequency. To obtain thenecessary operating precision, all aircraft clocks in thesystem are synchronized periodically.

The 2,000 slots provided by the "industry" system willservice more than 2,000 aircraft at one time since permanent slot assignments are not made to aircraft, the someslot can be used by any two aircraft that are separatedby at least 2300 nautical miles. Slot use is a function of"listening" and "squatting". To accommodate small numbers of aircraft the "industry" system also has an asynchronous (a version of interrogator-transponder) mode ofoperation to give protection in isolated areas not coveredby the time synchronization process.

Complication - for what Reason?What will be the Cost of the Equipment?

The time-frequency technology is more complicatedthan its predecessor techniques (interrogotor-responderand one-way ranging) by probably an order of magnitude. It is forced on us by planning for accommodatingthe vast number of a i rcraf t that we know must be accommodated. The numbers (Item 1 and 2) clearly show that thelargest segment of aircraft is contributed by general aviation. But, is the CAS going to be so complicated (and thuscostly), that general aviation cannot afford to install it?This, of course, is a tough question to answer at this earlydote in the development of time-frequency CAS technology.

The "industry" CAS system has as a part of its designwhat is known as a "limited equipment". It is "limited" inthat it is not called on to propagate the master time; ituses master time and obtains all necessary data. Significant complication was added to the complete (so-calledair carrier) version of the CAS equipment to permit this"limited equipment" version to be provided at the lowestpossible cost to general aviation. The best dollar figuresI can give you today is that the airline version will probably cost from $ 30,000 to $ 50,000 initially, whereas thegeneral aviation version will be below $ 10,000 — hopefully in the S 8,000 till $ 10,000 price range initially.

Thinking back over the post ten years, I recall that thefirst ATC radar beacons cost S 7,500 (early 1960 dollars)and today a much more comprehensive beacon costs$ 1,000. This is more than a 7 fold cost reduction. The costreduction come about as the result of digital circuit technology improvement. The CAS, like the ATC radar beacon,is a system that is based on digital logic. Therefore, theopportunity is present for simplif cation and cost reductionas solid state logic continues to improve. We have everyright to expect the general aviation CAS to cost in theorder of S 2,500 to $ 3,500 within 5 years.

CAS probably not a Gertrude Stein*

The time-frequency technology shows such great promise that it is very tempting to consider solving some otherexpected problems at the time the CAS system is beingconceived. In order not to endlessly delay obtaining theCAS, we adopted the policy of designing a GertrudeStein* CAS but at the same time made careful provisionfor system expansion to accommodate other functions including individual airframe identification. There is everyindication that the same airborne system can, in time, alsoprovide the ATC radar beacon and DME functions in thesame airborne equipment — with but few additions.

The way is relatively clear for this to happen and iscurrently being studied by FAA and others. The militarycan have its "Integrated CNI" equipment, however, the"common system" could very well have its integrated"Data acquisition-distance measuring equipment-airframeidentification and CAS" — all in a single airborne equipment. There is a prophecy for you.

Current Report on"Industry CAS-System Development Program"

A technical description of a time-frequency CAS systemwas generated by our industry effort after 6 months ofcountless meetings attended by selected time-frequencytechnology and system specialists. Since that time the technical description has been further refined. Currently theseventh revision of the document describing the system(ATA Report ANTC No. 117) is available for the asking.Five manufacturers are now building airborne systems,using the technical description as their Bible. In June ofnext year, when they are to be ready for the industry flighttesting program, we will find out if the technical description adequately defined the system and whether the fourmanufacturers' equipment will work cooperately in theflight test environment.

We have contracted v/ith Martin-Marietta (Baltimore,Maryland) to manage our industry flight test program.Currently, Martin-Marietta is building the data recordingand data reduction system which will permit us to evalu-ate flight tests.

Currently four airlines are evaluating CAS display devices using Link flight simulators. This is providing the CASprogram information on pilot and airframe reaction timein it is introducing a large cross section of airline pilots tothe CAS system and the current version of display devices.

By the fall of 1969 we expect to be able to advise youif the system we have designed on paper, and by then willhave flight tested, is an acceptable candidate for commonsystem application.

• Gertrude Stein's book "A Rose is a Rose is o Rose" for many yearshas provided the aviation industry a "jargon" way of describing adevice or system that provides a single function, and only asingle function.

Annual Conference 1970 — Montreat

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Digital CommunicationsBy B. F. McLeodDirector, Electronic Engineering,Pan American World Airways, Inc.to the 1968 RTCA Annual Assembly tvleeting

As predicted, the present air traffic control system andterminal area facilities have reached the saturation pointat many of our key cities. What can we expect in theyears to come?

Today, in the U. S., the airline fleet is growing at aboutone new jet per day. In about a year the B747's will beginto join this fleet, then the air buses and next the SSI airplanes with many new problems due to ever increasingairspeeds.

During recent years, as our air traffic system has beenexpanded to enlarge the regions of positive control, provide radar monitoring and vectoring, and accommodatethe ever increasing volume of air operations, we havewatched a tremendous build-up in air-ground voice communications. The very nature of the system has been todemand addi t ional vo ice communicat ion at a rate greaterthan the increase in air traffic flow. To accommodate ourcurrent system, a great number of controllers are neededon the ground to talk to the many pilots in the sky. Is itwise to continue to expand indefinitely this overtaxedsystem? We think not, but what is the answer? First, runway saturation must be avoided. Next, routine functionsmust be automated to bring about more efficient use ofrunways, time, space, equipment, and manpower.

One fundamental step in moving towards this objective is to get the airplanes to talk directly with flow control computers on the ground.

If automatic communications con help reduce presentproblems, why aren't we using it now?

Briefly glancing back, the Radio Technical Commissionfor Aeronautics' Special Committee 31 recommended in1947 a national air traffic control system employing VOR/DME, secondary radar, airborne transponder, alpha-numeric readout of aircraft position in ATC centers, and anL-band air/ground data link on a private line which wouldautomate routine air/ground ATC communications.

Lack of full follow-through on the SC-31 plan resultedin little progress being made on the L-band private line.However, during the postwar years there was a large shiftof voice communications from the HP band to static-freeVHP frequencies. In parallel with this wholesale shift toVHP, planning was developed in 1951 to include data linkcapability in new VHP voice sets. Again, lack of follow-through with complete system planning resulted in no progress with automated communications.

In about the same time frame, PanAm began a development to autom.ate a small, but very important functionof the over ocean HP communications system. Pilots flyinglong distance routes were often required to continuouslymonitor for ten hours or longer, one or more noisy HP

channels. This was a monotonous and tiring routine function ripe for automation.

In the South Pacific PanAm introduced the Selcal system which carried just one message from the ground to thepilot — "Please answer me". The system was simple, economical, and provided great relief to the pilot. He couldnow hang his headset on a hook and let a small electronicbox provide the monitoring. This system was soon accepted in the U.S. and later by ICAO. It can well be remembered that it was looked upon as so elementary that itslife would be extremely limited. To gain industry acceptance of it in 1951, we agreed to write it off in three years.Yet, 17 years later there is no modern replacement and itis currently being planned for SST's. There is the strongesthope, however, that today's efforts will produce a morecomprehensive digital communications system well beforethe SST's are ready for operation.

In 1959, a new thrust was made to develop on operational data link known as "AGACS" or automatic ground/air/ground communications system. Regrettably, this system was not brought into being to aid air traffic controland an airline study showed that it could not be economically justified for airline operational use alone. So, after21 years, the question is, "Are we now able to justify onautomated communications system?" We believe the answer is clearly yes! But why?

First, unlike in earlier years, today's navigation systems, both long and short range, provide the cockpit withcontinuous position information. Until recently, pilots onlydetermined on spot occasions, precisely where the airplane was. Also it has only been recently that sufficientground DME stations were available to make area navigation computers attractive to U.S. airspace users.

Second, it now appears that ATC requirements alone,or company operaMonal requirements alone, are greatenough to justify automated communications on both longrange and short range routes.

Third, the feasibility of long distance — up to 8,000miles — VHP circuits using satellite relay has been demonstrated. These circuits provide the reliability and quality that is needed to support digital communications onlong distance international routes.

And fourth, RTCA's committees, SC-100, SC-llQ andin, have provided the guidelines that have been neededto move forward with the planning of a universal digitalcommunications system.

How do we best get going? PanAm has established along range objective called a "Plight Information System".In this planning, digital communications is a fundamentalelement of the total system.

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The function of the Flight Information System will beto collect, analyze, transmit, store, receive, and presentinformation required by:

Air Traffic Control and Advisory Services,The Flight Crew, andCompany Offices.

Let's briefly look at the component parts of the system,the benefits derived, and the relationship of each to digitalc o m m u n i c a t i o n s .

First, the "AIDS" or maintenance portion of the systemwiW serve a two-fold purpose: fault detection and analysisof complex aircraft systems and performance analysis ofthe engines.

The prime objective of "AIDS" will be to detect trends,faults, and out of tolerance conditions to permit expeditious correction action. Today, many airlines includingPanAm, manually record data on engines and other systems for later trend analysis. A few airlines record thisdata automatically for later analysis on the ground. Thedisadvantages with each of these methods are:

1. the time lapse between recording and analysing thedata, and

2. the task of centralized handling of the great volumeof data produced by a large fleet of aircraft.

To eliminate both of these disadvantages and to provide only significant maintenance information to the crewand the ground, PanAm proposes to use onboard processing. By measuring first order information, rejecting redundant data, and analysing the remaining data for tolerance and short term trend, information significant to the further operation of the aircraft canbe provided in advance to the ground via digital communications. A cockpit readout will provide the same information to the crew. Our study indicates that such asystem has a great potential for improving maintenanceefficiency, aircraft utilization, and reducing delays.

A second part of the "Flight Information System" isthat which will provide information to the company operations department. To efficiently control a large fleet ofaircraft, an airline must know their location and operational status. Combined with digital communications, onboard position determining equipment such as Doppler,Inertial, and VOR/DME can provide company dispatchoffices with real-time flight following information. Anoperations recorder of the "endless loop" type is anticipated, making available as desired operations information for the past 24 hours or greater. This capability combined with on-board analysis will permit private review ofpilot and autopilot inputs to the controls and aircraft operation. In the event of an emergency or abnormal aircraftoperation, vital parameters will be fed into the digitalcommunications system for automatic transmission.

Two other company departments to be served throughthe Flight Information System will be the Passenger Service and Accounting organizations. Special passengerhandling requirements generated in the main cabin byflight service attendants can be fed into the digital communications system and automatically routed to the proper ground recipient.

Today, the airline accounting department computes aircraft and crew flight time from manual entries made bythe crew on the aircraft at departure and arrival. TheFlight Information System can automate this process and

feed the information directly to the Accounting Department's computer.

A key function of the Flight Information System is toserve the Air Traffic Control and Advisory Services. Thedevelopment of this feature will require close government/industry coordination with the prime objective being toautomate as many routine functions as possible.

For long range over ocean operation we believe asubstantial reduction can be made in aircraft spacing, ifby automatic means air derived position fixed of goodaccuracy are frequently reported back to a relativelysimple ground flow control computer. As traffic volumesincrease in the 1975-1985 period and there is a need forcloser spacing, further monitoring by satellite is expectedto be an important addition.

For U. S. domestic operation aircraft plan position information may be ground derived and supplied to flowcontrol computers, or could be air derived and suppliedby the digital communications link. In 1957 it was plannedthat position information would be ground derived, however, we believe that this conclusion is open for review forcer ta in c lasses of a i rcraf t .

It is important that a clear readout, either on a cathoderay tube or on a printed sheet, be available to the pilot forreceiving take-off and enroute instructions.

Area navigation capability by the cockpit is urgentlyneeded. It appears that this can best be provided by pictorial displays with preplanning making many paths available to and from runway approach gates. These variouspaths, plus speed control, may be used for sequencing ofaircraft and at the same time reduce the need for givinga large number of instructions to pilots.

PanAm has made a start toward implementation of aFlight Information System by placing a limited Digicomsystem in operation on an experimental basis. In the interest of getting under way now, this test will only involvean air-to-ground capability for the first six to eight months.This test is being conducted between New York and theCaribbean using a B707 aircraft. Upon command from thecockpit, messages containing aircraft identification, position, and engine performance data are sent for receptionby an FAA station at Avalon, N.J. and a PanAm stationat JFK. Use of the Avalon station is being made availablethrough the excellent cooperation of the Research andDevelopment Service of the FAA.

Pending the installation of Doppler navigation on this707 airplane, position information will be set in manually.

Engine data is sensed by equipment built by GeneralElectric and converted to a digital message. Data transmissions are fed through a Bendix Radio modulator-demodulator to a third VHP transceiver (Bendix RTA-42A)on the aircraft. When the messages arrive at a groundstation, they are routed by telephone line to a computerin the PanAm Building for processing and to the airlineelectronic switching system at Cedar Rapids for distribution by teletype to the proper addresses. A cathode raytube readout is also available in the PanAm Building.

The objective of this test program is to gather datawhich will help define the characteristics of digital communications hardware and operational procedures, andat the same time perform a useful service to daily operat i o n .

The second phase of this program calls for five or moreparticipating aircraft with two-way equipment being automatically interrogated from the ground. For PanAm's

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operation, it is desired that VHP satellite circuits be available, but if there is a delay then normal and extendedrange VHP facilities will be used.

The next step will be full fleet implementation withpriority being given to the B747 airplanes.

Once again a beginning has been made. More thanever before, the industry has become acutely aware of thepotentials of digital communications and the role it willplay in tomorrow's environment.

A few months ago the PAA Associate Administrator forDevelopment stated, "We can not tolerate the amount ofair-ground voice communication that exists now — digital

communications with an air-ground data link is needed".The Air Transport Association Operations Committee hasendorsed development of digital communications. Airincis providing coordination for the U.S. airlines. We arewilling to accept a leading role in developing this system,and look forward to working closely with all concerned tobring about a common digital communications system. Porit to be a common international system — as it must —we foresee a need for considerable coordination throughPAA, lATA, and finally the establishment of Recommendations and Standards by ICAO. The talents and skills ofmany are truly needed to bring a digital communicationsto an operational status by 1971.

An Airport Surface Traffic Control System(STRACS)

By Louis AchitoffChief, Aviation Technical Services Division,The Port of New York Authority,t o t h e R a d i o Te c h n i c a l C o m m i s s i o n f o r A e r o n a u t i c s

1968 Annual Assembly

The System

In approximately one month, a test installation willhave been completed at Kennedy International Airportand evaluations begun to determine whether the presenceof individual aircraft can accurately, consistently and reliably be detected on an airport taxiway system by othert h a n v i s u a l m e a n s .

This will complete Phase A of The Port of New YorkAuthority Aviation Department's STRACS (Surface TrafficControl System) program which, if successful, should culminate in aviation's first automatic ground control system,thereby making it possible to systematize aircraft movement from departure gate to arrival gate.

The STRACS program is the direct outgrowth of theneed to resolve problems created by the advent of long-bodied aircraft (B-747) and the congestion resulting fromthe ever increasing runway movement rates. The need toaccommodate "jumbo" aircraft at Kennedy has causedthe following progression:

1. construction of high fingers to permit second level aircraft loading and consequent obstructing of line ofsight from control tower to portions of taxiway system;

2. increase in gate space per airplane;3. increase in total apron area;4. push-out of taxiways closer to runways; and5. insufficient distance between runways and taxiways to

store aircraft leaving runway.

The erection of high apron fingers appropriate to B-747aircraft results in the loss of direct line of sight as well asASDE control of most of the inner taxiways at Kennedy.

The inability to store long-bodied aircraft between arunway and the adjacent taxiway, 400 feet away (centerto center), simply means that if an aircraft exiting the runway cannot continue its motion because of the presenceof other aircraft on the adjacent taxiway, operations onthe runway must cease until safe clearance is established.

The total eeffct of the above two situations would be aslowdown of airport traffic, the rectification of which dictates an automatic ground control system which,

1. ensures unobstructed taxiing tracks for priority aircraft;2. removes the tower operator from the ground control

loop to the greatest extent possible;3. materially reduces communications workload; and4. provides superior taxiing guidance during Category II

w e a t h e r.

Having defind the problem, a broad statement of thedesired objectives and preliminary characteristics of aSTRACS was developed and used as a basis for a requestfor proposals from various manufacturers of surface traffic control equipment as well as others with records ofachievement in traffic control system design.

In brief, the preliminary functional specification described a noncooperative system and called for:

a) Detection of aircraft.b) Identification.c) Guidance on the taxiways.d) Display in the tower.e) Fail safe alarm logic.f) Priority routings.g) Conflict protection.h) Override capability to afford manual control.

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A number of excellent, imaginative proposals for totalsystem design v/ere received from companies with extensive experience in vehicular traffic control — primarilybecause of their famil iarity with off-the-shelf detectionhardware. It became apparent, after analysis and discussion with the proponents, that ground traffic control systems can be developed to almost any degree of sophistica t ion by the use o f computer techno logy, prov idedreliable and consistent detection can be accomplished.

Consequently, it was decided that the Port Authoritywould move ahead with STRACS according to the following plan:

A ) D e t e c t i o nAirborne Instruments Laboratory was retained as a

consultant to analyze and evaluate the detection systemsincorporated in the proposals which had been submitted.In addition, AIL was to render judgment on the state-of-the-art detection devices which have appeared in the litera tu re f rom t ime to t ime.

Upon completion of the above paper evaluations, themost promising detection devices would be installed in anactive taxiway at Kennedy and a full scale test would beperformed over a period of several months to determinethe characteristics of the devices and their ability to reliably detect the types of aircraft currently operating atKennedy. Extrapolation of the data to B-747 and Airbuswould, of course, depend upon its quality and accuracyas well as the theoretical considerations upon which thedesigns of the devices are predicated. Another possibilitywould be to obtain readings from a C5A taxiing operationif such could be arranged.

B ) S y s t e m D e s i g n

This phase is initiated with the preparation of a detailed functional specification around the detection systemdetermined in (A) to have met requirements.

It is intended that STRACS will permit the followingoperation to occur: Federal Flight 129, having been cleared to land, the controller inserts a card into a computerwhich takes the destination terminal and predeterminedtaxi track and integrates it with the signal from a sensoras the airplane leaves the runway. The airplane followsvisual stop or go, and directional signals along its taxiroute which protects it from conflicting traffic at intersections, until its arrival at the destination terminal apron.The computer stores the tracks of all moving aircraft, determines ground speed from sensor information, predictsand then prevents conflict with other arriving and departing aircraft.

The controller's display indicates occupancy or vacancyof any taxi segment and permits immediate computer interrogation to identify an occupant.

C ) S y s t e m C o n s t r u c t i o n

The preparation of the engineering specification, installation and system checkout completes the program.Within Phase C, it may be possible to activate subportionsof the total system prior to 1971. These might include, forexample, detection only, followed by verbal communication, or detection plus guidance without computer track

ing. What is important is the concept of building blocksso that subsystems may be added on.

FAA System RequirementThe FAA, in a position paper prepared for presenta

tion to the Fifth Air Navigation Conference (ICAO) convened in Montreal, November 14, 1967, stated that "inview of trends to increased traffic, larger more complexaerodromes, predicted all-weather operations, and designcomplexities of aircraft requiring highly efficient groundhandling, it seems reasonable to pursue certain improvements to the system".

The improvements are embodied in a document entitled "U. S. Design for an All-Weather Aerodrome SurfaceTraffic System".

The system design is the direct outgrowth of a SystemRequirement established by the Associate Administratorof Plans on September 13, 1966 to develop an all-weathersurface guidance and control subsystem. In the prescribingof this requirement, it was declared that:

"The need is already urgent at high activity airportsand will become more critical with the gradual reductionof approach minima down to complete all-weather operations. Development and installation should keep pace withthe lowering of weather minima. Priority should be givento development of those components which can be selected and implemented in the shortest possible time."

I C A O A c t i o n

The final report of the committee assigned the responsibility for the Movement of Aircraft and Vehicles on theGround, Agenda Item 2 of the Fifth Air Navigation Conference, under the Chairmanship of the leader of the U. S.delegation, affirmed the need for an all-weather aerodrome guidance and control subsystem. It went on toprescribe the following criteria which should be considered in the design of the subsystem:

A) The pilot must have:1. steering and distance information in order to track

along the runway, decelerate, and reach the turn-offpoint safely and efficiently;

2. visual information along the route to be followed;3. position information along the route to be followed;4. assurance of separation; and5. adequate warning for changes of direction or the need

for speed adjustment.

B) The Controlling Authority must have:

1. information on the position and progress of each aircraf t at a l l t imes;

2. information on the position and progress of essentialground traffic at all times;

3. information on the presence of obstructions and temporary hazards; and

4. information on the operational status of the system inu s e .

C) Ground Vehicles must be assured of:1. adequate routing, navigation information and means

of collision avoidance to permit rapid access to anypart of the aerodrome, and, also, if practicable and

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economic, outside the perimeter. Crash location equipment must also be considered; and

2. safe and positive routing as they fulfill their roles ofattending to the essential needs of aircraft passengers,and airline and aerodrome personnel and services.

The official recognition by both the FAA and ICAO of

the need to move ahead promptly with the design andimplementation of a STRACS has lent impetus to the PortAuthority program. It has also been instrumental in promoting an active exchange of information and, it is hoped,on increasing involvement of the FAA in the program sinceits success will depend upon its acceptance by FAA controller personnel.

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The Canad ian A i r Tra ffic Cont ro l Assoc ia t ion Convention "CATCA '69" will be held from 6th till 7th May, 1969.

The Hon. Paul T. Hellyer, Canadian Minister of Transport, has consented to be guest speaker and Ted Bonnerof the Decco Navigator Co. the Master of Ceremonies atthe Conference Banquet on May 7th.

F. Lee Bailey, prominent Boston lawyer, instrumental inthe founding of the U. S. Professional Air Traffic Controllers Organization, will be guest speaker at the President'sLuncheon on May 6th.

An excellent program of technical presentations willbe featured on the following topics:

T o p i cRadar Digital Processing and Display Systemfor A i r Tra ffic Con t ro l

S p o n s o rA i rborne Ins t rument Labora to r ies

T o p i cArea Navigation

S p o n s o rComputing Devices of CanadaT o p i cATC Data Processing Philosophy

S p o n s o rElliott Brothers (London) Ltd.

T o p i cTerminal Control in the Seventies

S p o n s o rDecca Navigator System Inc.T o p i cThe Atmospheric Environment in Relationto Aircraft OperationsS p o n s o rThe Nat ional Research Counci l of Canada

T o p i cLanding Weather Minima InvestigationS p o n s o rU.S.A.F. Flight Dynamics LaboratoryT o p i cThe Concorde

S p o n s o rThe British Aircraft CorporationT o p i cCanadian Air Traffic Control System, in the '70'sS p o n s o rThe Department of Transport

1968 - an active Year for the Netherlands' Guild

When the Netherland's Guild held her Annual Meeting in late October, 1968, Members and Officers couldproudly look back to a successful year.

Within a period of twelve months, the membership ofthe guild increased by more than 25%, from 80 to 118.

Contacts with General Aviation have been fostered.The Guild oFFered her assistance to the Royal Netherlands' Society of Aviation and the aeroclubs associatedwith this organization. This offer includes speaches andpresentations by the Guild about air traffic control andgeneral aviation to be given any time and any place inthe Netherlands. In this context, a very lively panel discussion was recently held with the Dutch Aeroclub.

Very fruitful contacts are also maintained with theDutch Air Line Pilots* Association. A series of workingsessions has been arranged, with particular emphasis onthe following subjects:— Radar assistance in adverse weather conditions;— Automatic lock-on in the final approach phase;

— Use of parallel runways (this subject is particularlytopical with Schiphol now having 01/19 L and R);

— Reduction of R/T load.

A presentation about the Eurocontrol Upper Area Control Centre at Maastricht/Beek (Southern Netherland) isplanned for April. It will be given by a member of theEurocontrol H. Q. at Brussels. Among the various papersproduced by the Guild during 1968, proposals to Standing Committee I for streamlining the IFATCA Manual anda report about the current position of the air traffic controller in the Netherlands deserve particular mention.

The Annual Meeting elected the following Board ofO f fi c e r s :

T h , M . v a n G a a l e n P r e s i d e n tF. M. J. Mente SecretaryP . K o l f f T r e a s u r e rB . H . v a n O m m e n M e m b e r — I FAT C A a f f a i r sA . V i n k M e m b e r — P u b l i c i t y

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P a c i fi cS A RS y m p o s i u mBy Tirey K. Vickers

C h i e f s t i m u l u s f o r t h e S y m p o s i u m w a s t h eimpending introduction of the 747 aircraft (top),w h i c h i s c o m p a r e d i n t h i s p i c t u r e w i t h t h epresent 707. Fully loaded, a 747 will be 2.5t imes as l i ke ly to have a deranged possengero b o a r d ; i n a c r a s h o r d i t c h i n g , i t w i l l h a v e2 . 5 t i m e s a s m a n y p a s s e n g e r s t o e v a c u a t e .

Three hundred and one registrants from eight countriesattended the Pacific Air Safety and Rescue Symposium inSon Francisco, October 29 — 31, 1968. The meeting wassponsored by the U.S. Coast Guard and the Federal Aviation Administration. The main topic was ditching (land-plane emergency water landings) with particular referenceto Pacific search and rescue (SAR) operations.

The program started with the audio-visual presentation"Mission Possible", which combined color sl ide/movie/sound track/live medio to depict the roles of the U.S.Coast Guard and the FAA in SAR procedures. Put togetherby LCDR Lee Levy of the Coast Guard, Doug Hughes oft h e C o a s t G u a r d R e s e r v e , a n d W i l l i a m O ' N e i l l o f t h eOakland ARTC Center, "Mission Possible" was easily themost spectacular and entertaining event of the 2V2 daysymposium.

A panel session on post-ditching problems revealedthat NASA may become port of the Pacific SAR network,using their elaborate setup designed for recovering astronauts at sea. One of the panel members, a Western AirLines stewardess, brought up a number of pointed questions about the emergency evacuation of airline aircraft.She would like better restraints for galley equipment,which tends to spill all over the cabin in a crash or ditching. She would recommend that able-bodied men, ratherthan women, children, or elderly persons, always be seatednext to the emergency exits. She would like to prohibit theunder-seat stowage of passenger baggage, because of itspotential interference with life preservers (also stowedunder the seats) and because such baggage can clutter thea i s l e s a f t e r a c r a s h .

In an interesting paper, "Hydrodynamics of Ditching",James F. Goodwin of McDonnell Douglas reviewed theairline ditching accidents of the post 15 years. There havebeen 18 since 1953; 8 of these were pre-meditated, while10 happened suddenly — usually right off the airport. Because of the phenomenal reliability of jet engines, therehas never been a pre-meditated (d la 1947) type ditchingof 0 jet liner — but with more passengers carrying gunsthese days, nobody con guarantee it won't happen someday. The impending introduction of much larger aircraftwill increase the potential size of the rescue problem.

M r. G o o d w i n d e s c r i b e d f e a t u r e s w h i c h w i l l e n h a n c ethe ditchability of the new DC-10 airbus. Fuselage skinthickness has been increased, from .090" on the DC-8, to.125" on the DC-10. An extra floor in the lower baggage

section will moke the DC-10 fuselage about 50% strongerthan the DC-8, one of which recently survived a ditchingin Son Francisco Bay with little structural damage.

CDR Robert C. Powell described the Coast Guard's present Research and Development program. One projectinvolves the analysis of a vast amount of data on meteorology and oceanography, to come up with better estimatesof wind and current drift for various types of life boatsand life rafts. New designs for Coast Guard surface vessels and helicopters ore expected to increase range andperformance for SAR operations. CDR Powell said thatbetter search radars are needed, in order to detect non-cooperative targets such as plastic or rubber life rafts.R. C. McGuire of FAA reported that Pacific airline trafficis expected to increase to 91,000 operations per year, in1 9 7 2 .

Subsequently the Symposium split into a number ofsmall groups or "workshops" which spent several hoursdiscussing various facets of the SAR problem, and preparing recommendations for presentation on October 31.

In the Air-Sea Coordination Workshop, it was statedthat 90% of the SAR problem relates to communicationsdifficulties; and one of the biggest coordination problemsis the lack of communication between aircraft and surfaceships. At any given moment there are approximately 9,000surface vessels plowing accros the ocean of the world.Most of them hove only one radio operator, who standsan 8-hour watch daily. Although the watch schedules oregenerally standardized in different parts of the world,ships of U.S. registry do not necessarily conform to theprevailing schedules.

There is now on agency in New York City calledAMVERS (Automatic Merchant Vessel Reporting System)which, using a large computer, receives and stores sailingplans of about three-fourths of the total number of merchant vessels, and updates their positions periodically bydead-reckoning and actual positian reports. When onemergency happens anywhere in the world, AMVERS con,within a few minutes, determine the names of the shipswhich are in the most likely position at that moment todivert, and look for survivors. But getting in contact withsuch ships is still a problem because of the watch scheduleproblem. Most ships maintain a radio watch on either ofthe international distress frequencies of 500 or 2182 Khz.Many of them hove an automatic alarm to alert the radio

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operator if he is within earshot. As yet, however, there isnothing corresponding to SELCAL to alert a designatedship; so even in this supposedly enlightened age, theestablishment of communication with a designated shipcan still be a difficult problem. Even when the ship is contacted, language barriers can form a further handicap tov o i c e c o m m u n i c a t i o n s .

There is no incentive for ships to carry aircraft distressfrequencies of 121.5 or 243 Mhz. Although a number ofaircraft carry the 2182 Khz distress frequency, aircraftantennas for this band are not very efficient.

Another handicap to efficient search and rescue ispoor navigation. If the pilot in difficulty does not knowwhere he is, he can be very difficult to locate. Joe Farra-rese of FAA Flight Standard reviewed the FAA's proposedrequirement for crash locator beacons on civil aircraft. Fiepointed out that during the last 10 years, 31 aircraft, carrying a total of 57 people, have presumably crashed withinthe boundaries of the U. S. but have never been found.

Several types of crash locator beacons were displayedat the Symposium. As the tail section of an aircraft is thelast thing to crumple in a crash, it nearly always remainsintact; for this reason, the little radio beacons are designed for installation inside the vertical fin (see Fig. 1). Triggered off automatically by a crash, they can broadcast asweeping-tone signal on 121.5 and 243 Mhz, for severaldays.

On the afternoon of October 30, KLM presented oninteresting description of their new evacuation simulatorfor training cabin attendants in all types of emergencyprocedures. The simulator includes full-scale mock-ups ofsection of two types of KLM aircraft cabins including seats,doors, emergency exits, etc. It also includes facilities forfilling the cabin with smoke, and uses an audio system tosimulate the sound effects of a crash. Simultaneously, thecabin can be suddenly dropped 15° on one side. Cockingthe cabin on one side has the effect of reducing the aislewidth, and increasing the difficulty of evacuating passengers. The floor outside the trainer can be lowered 10feet, to require the use of passenger chutes for evacuation.Instructors con watch cabin personnel in training, throughone-way mirrors, to determine how well they handle thevarious emergency procedures.

\

Fig. 1 Installation details of Garrett SAR beacon and its twin antenm

On the last day of the Symposium, the various workshops made their reports to the assembly. Their recomm e n d a t i o n s i n c l u d e d t h e i t e m s l i s t e d b e l o w .

I t w a s r e c o m m e n d e d t h a t a S A R c o o r d i n a t i n g c o mmittee be established by the Department of Transportation, to supply a means of communicating SAR problemsand solutions to all concerned, and to evaluate all newSAR equipment. Such a committee had been suggested ontwo previous occasions but had never been set up. It wasrecommended that the committee include representativesfrom Coast Guard, FAA, DOD, lATA, AOPA, and ALPA,with technical support furnished by the Society of Automotive Engineers.

Present survival equipment has many short-comings;alerting, locating, evacuation, and ditching regulationsand procedures need to be brought up-to-date. A surprising number of general aviation aircraft exported from theUSA are ferried across the ocean to their destination. Amajor problem to the Coast Guard in the Pacific area isgeneral aviation aircraft getting into difficulties while conducting oceanic flights without long-range communicationequipment. A Coast Guard representative reported thatalmost every month some general aviation pilot enroutefrom California to Hawaii gets lost and low on fuel. Anumber of colls for help on 121.5 Mhz hove been intercepted and relayed by airline pilots, to alert SAR rescuefacilities to locate the aircraft and guide it to a safe landing, or a ditching alongside a surface ship. It was recommended that regulations be broadened to require a positive capability for long-range air/ground communications,plus appropriate life support equipment, for any generalaviation aircraft embarking on long-range oceanic flights.

The evacuation of jumbo jet aircraft is expected to beenhanced by the use of double-width doors, wide aisles,and large inflatable slides which can double as life rafts.The deployment of life rafts will be facilitated by storingthem above each door, rather than elsewhere in the cabin.One workshop group recommended that life-raft survivalkits be re-evaluated — there is more need for thermalblankets than for life-raft canopies. Also there is less needfor carrying long-term food rations, due to the shorterreaction time of rescue or re-supply aircraft.

As a fully loaded 747 will be 2V2 times as likely as afully loaded 707 aircraft to have a deranged passengeraboard, it was recommended that the FAA Office of Aviation Medicine prepare a training text for airline crewsto deal with the handling of such persons.

A large number of surface ships are now equipped withthe SAR 156.8 Mhz FM channel; it was recommended thatthis frequency be installed in SAR aircraft for better air-sea coordination. It was also recommended that in thedevelopment of satellite communications, adequate consideration be given in providing channels for SAR comm u n i c a t i o n s .

During the Symposium, three hundred people spent atotal of 6,000 man-hours reviewing SAR problems. Was allthis time and expense justified? The opening of the newPacific routes with jumbo jet aircraft will put a lot ofpeople over deep water. Unpreparedness of the CoastGuard or the FAA for a jumbo jet ditching in mid-Pacific— if it ever happens — will be awfully hard to live down.If meetings of this type can set off action to eliminatesome of the potential problems of such an event — remotethough it may be — then the Pacific Air Safety Search andRescue Symposium served a useful purpose.

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W h a t ' s N e w i n M o n t r e a l ?

A S e l e c t i o n o f R e c e n t I C A O A c t i v i t i e s

I C A O C o u n c i l E l e c t e d O f fi c e r s

The ICAO Council, governing body of the InternationalCivil Aviation Organization, has elected its Vice-Presidentsand Committee Chairmen, following the 16th Assembly ofICAO held recently in Buenos Aires. The President of the27-member Council, V/alter Binaghi, has announced theelection of the following Council members:

A. El Micheri (Tunisia), 1st Vice-President of the Council; F. Novak (Czechoslovak Socialist Republic), 2nd Vice-President of the Council; Dr. E. Vdsquez-Rocha (Colombia),3rd Vive-President of the Council; F. X. Ollassa (CongoBrazzaville), Chairman of the Air Transport Committee;Reor-Admiral (Retired) J. M. Van Olm (Kingdom of theNetherlands), Chairman of the Committee on Joint Support of Air Navigation Services; and N. Nakano (Japan),Chairman of the Finance Committee.

Unlike others, the Legal Committee of ICAO is a permanent one. It is open to membership by all ContractingStates. The Committee elects its own Chairman for theduration of its session for which it convenes, generally,once a year. ICAO has now 116 Member States.

Feasibility Study on System Planningfor the Introduction of New Aircraft Types

Based on a Resolution (A16-5) adopted at the SixteenSession of the ICAO Assembly, the Secretary General hasproposed to the Council a programme for a FeasibilityStudy on Systems Planning for the Introduction of NewAircraft Types. The following principal steps in the studyhave been contemplated:1 . de te rmina t ion o f what a i rc ra f t charac te r is t i cs and o ther

factors are likelyto be significant in assessing the effectupon the infrastructure and the community of the introduction of a new aircraft type;

2. exploration of the possibility of obtaining usable inf o r m a t i o n o n t h e a b o v e f a c t o r s b e f o r e t h e r e l e v a n tdesign features of a new aircraft are frozen and theproduction process commenced;

3. consideration of ways in which the above information,to the extent that it appears obtainable, may best bepresented to States to assist them in assessing thebenefits and penalties associated with the new aircraftt y p e ;

4. evaluation of the workload that would fall upon Statesand the representative bodies and Secretariat of ICAOin making such assessments of future new aircraft types,and of any budgetary implications for ICAO;

5. evaluation of the practicability of the systems planningapproach, taking into account the benefits expected tocome from it and the difficulties and cost of applying it.

❖

The P rob lem o f t he Son ic Boom

Sonic boom has been specifically mentioned in the various ICAO studies which have been produced on the problems associated with the introduction of supersonic transport aircraft (SST) into commercial service. For example,references to sonic boom are included in Doc 8087-C/925— "A Preliminary Study of the Technical, Economic andSocial Consequences of the Introduction into CommercialService of Supersonic Aircraft" and in Addendum No. 2thereto. Furthermore, the Organization's more recent studies (Draft Doc 8366-AN/880, Draft Doc 8366-AN/883 andDraft Doc 8366-AN/883/2, all entitled "ICAO and the Technical Problems associated with Supersonic Transport Aircraft"), each accords the subjects of sonic boom a separate subchapter. The attention being given to this subjectreflects the Assembly's identification of the problemthrough Resolution A14-7, as one likely to require comprehensive study by ICAO, and on which States should bekept informed.

The Technical Panel on Supersonic Transport Operations (the SST Panel) formed by the Air Navigation Commission in February 1968, in replacement of the SST StudyGroup, discussed sonic boom, at its First Meeting in July-August 1968 and reported that "looked at from a purelytechnical and operational viewpoint, SSTs will operatemost efficiently if there is no limit imposed on sonicboom"; this statement was made in the light of agreementthat policy decisions on sonic boom should be taken onlyafter consideration of data obtained from actual flighttests. However, the Panel's attention is limited, under itsterms of reference, to consideration of operational andtechnical matters, whereas the problems associated withsonic boom involve also the economic, legal, social, physical, physiological and psychological fields.

The Sixteenth Session of the Assembly, acting on a proposal submitted jointly by Austria, Denmark, Federal Republic of Germany, Ireland, Sweden and Switzerland, adopted Resolution A16-4.

Resolution A16-4 (Commercial Introductionof Supersonic Aircraft):

V/ h e r e a s in the period since the Fourteenth Sessionof the Assembly which in Resolution A14-7 specially requested that supersonic aircraft should be able to operatein commercial service without creating unacceptable situations for the public due to sonic boom, experience andresearch in respect of this phenomenon have suggestedthat suitable action will have to be taken to prevent theparticular problems to which it might give rise, such asinterference with sleep due to the sonic boom and injurious effects to persons and property on land and at seacaused by the magnification of the sonic boom.

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Whereas the Council has set up a Panel to studythe technical problems associated with the commercialintroduction of supersonic aircraft.

W h e r e a s t h e S t a t e s i n v o l v e d i n t h e m a n u f a c t u r e o fsuch supersonic aircraft, as well as other States, are carrying out intense research into the physical, physiologicaland sociological effects of sonic boom.

T h e A s s e m b l y :

1. Reaffirms the importance it attaches to ensuringthat no unacceptable situation for the public is createdby sonic boom when supersonic aircraft are introducedi n t o c o m m e r c i a l s e r v i c e .

2 . I n v i t e s t h e S ta te s c o n c e r n e d t o f u r n i s h r e l e v a n t i nformation concerning the operating characteristics ofsuch aircraft, together with the results of their researchinto the effects of sonic boom, as soon as these areava i l ab le .

3. Instructs the Council, in the l ight of informationalready at hand and the information referred to in (2)above, and availing itself of the appropriate machinery, to review the Annexes and other relevant documents, so OS to ensure that they take due account ofthe problems which the operation of supersonic aircraftmay create for the public and, in particular, as regardssonic boom to take action to achieve internationalagreement on measurement of the sonic boom, thedefinition in quantitative or qualitative terms of theexpression unacceptable situations for the public"and the establishment of the corresponding limits.

4. Invites the States involved in the manufacture ofsupersonic aircraft to furnish ICAO in due course withproposals on the manner in which any specificationsestablished by ICAO yould be met."In accordance with this Resolution, the ICAO Secretary

General has presented a paper (C-WP/4902) on the Problems of Sonic Boom to the Sixty-Fifth Session of the Council, which discusses the problem in general and presents astaged plan of action,directed towards resolving the manyproblems associated with sonic boom. The plan envisagesthe following stages:

Stage 1 . Initiation of action directed to achievinginternational agreement on on acceptable and practicalmethod of describing and measuring sonic boom in termsrealistically representative of its degree of disturbance tohuman beings. This stage to include the establishment ofa unit of measurement of sonic boom, and the development of definitions of the terminology to be used.

Stage 2. Definition in quantitative and qualitativeterms, suitable for international application, of the expression "unacceptable situations for the public", usingfor this purpose the unit and means of measurement established under Stage 1.

Stage 3. Recommendation, for international application, of corresponding limits of acceptability, probablyover a representative range of environments such as densely populated areas, sparsely populated areas, potentialavalanche areas, coastal water, etc. taking due account ineach case of the possible need to establish separate daytime and night-time limits.

Stage 4. Consideration of the need to developadditional provisions for the prevention of adverse effectson livestock and property.

Stage 5. Recommendation of appropriate amendment of the ICAO Annexes and associated documents, us

ing the limits set in Stage 3.Stage 6. Convening of a world wide conference

aimed at establishing ICAO agreements related to sonicboom, taking into account the recommendations developed during Stage 5 and the proposals made by States onthe subject of the fourth Resolving Clause of ResolutionA 1 6 - 4 .

At on appropriate Stage of the programme, the Council should take the action necessary to encourage SSTmanufacturing States to furnish ICAO with their proposalson the subject of the fourth Resolving Clause of ResolutionA 1 6 - 4 .

Regional Supplementary Procedures

Rat ional izat ion of Document 7030

In April 1968 the Air Navigation Commission commenced preliminary action on a number of issues related to thecontent and format of the Regional Supplementary Procedures (SUPPS) in Doc. 7030.

Meanwhile the ICAO Secretariat has developed draftproposals to rationalize the presentation, format and content of the SUPPS, which include:

a) Alignment, in the interest of uniformity, of SUPPS whichdiffer only slightly from each other or vary because ofthe different time-periods which hove elapsed sincethey were introduced;

b) transfer to the relevant Annexes or PANS of any existing SUPPS which are, or might be, universally applied;

c) a new method of indicating the area of applicabilityof the SUPPS;

d) discontinuance of the publication of the "degree ofnon-application" (i.e. "differences") of the SUPPS;

e) a presentation of the SUPPS in a more convenient form.The draft proposals have recently been presented to

the ICAO Member States for comment, on the basis ofwhich the Commission will continue its study on the rationalization oft he SUPPS and will propose definite actionto the ICAO Counci l .

Growth in Civil Aviation

1968: Another Good Year in the Faceof Difficult Circumstances

As far as can be judged from the statistics now available, the world's airlines will have broken all traffic records in 1968 in spite of a combination of economic,social and political circumstances in many countries, particularly in Europe, which were hardly propositious for thedevelopment of international air travel.

According to estimates released in late December,1968, by the International Civil Aviation Organization forits 116 Member States, by the end of the year the airlines

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will have carried 261 mill ion passengers for a total of308,000 million passenger-kilometres (191,500 million passenger-miles) on scheduled services, representing increasesof 12% and 13% respectively over 1967. These growth rotesore definitely lower that those recorded from 1966 to 1967( + 17% for passengers and +19% for possenger-kilo-metres/possenger-miles) which is attributed mainly to theevents mentioned above. (It should also be borne in mindthat the 1966 global statistics were considerably influencedby the strike of airline personnel which paralysed operations of five major United States airlines during the summerof 1966, with the result that the traffic growth rotes recorded from 1 966 to 1967 were somewhat inflated.)

Freight and excess baggage will reach a total of 7,940million tonne-kilometres (5,440 million ton-miles) i.e. 19%and 29% more than the preceding year. These increasesof 1,240 million tonne-kilometres (850 million ton-miles) offreight and excess baggage and 540 million tonne-kilometres (370 million ton-miles) of mail are the highest civilaviation has yet known. It should be remembered that forseveral years the development of air mail has been clearlyinfluenced by events in Viet Nam (gains of 21% from 1964to 1965, 39% from 1965 to 1966, 24% from 1966 to 1967and 29% from 1967 to 1968).

In 1968, the global air traffic (passenger, freight, excessbaggage and mail) of all airlines of ICAO N^lember Statesrose to 37,450 million tonne-kilometres (25,650 million ton-miles), which is about 3.4 times greater than the 1959 traffic figure, thus giving an average annual growth rate ofc l o s e t o 1 5 % f o r t h e t e n y e a r s 1 9 5 9 - 1 9 6 8 . I C A O

Airlines launch ATC Study

The scheduled airlines of the United States have begunon intensive study to determine how today's air trafficcontrol system should be remodeled to handle safely andefficiently the expected growth of aviation during the fores e e a b l e f u t u r e .

Acting on a recommendation of the 1968 Airline Operations Conference of the Air Transport Association (ATA),the A i r l i ne A i r Tra f fic Con t ro l Commi t t ee has es tab l i shedan Air Traffic Control System Planning Group, under thechairmanship of Mr. E. V/. Pike, director of air trafficmanagement for Mohawk Airlines. Other members of thework ing g roup inc lude representa t i ves o f Amer ican ,Eastern, Pan American, Trans World, United and Northw e s t A i r l i n e s .

The working group is currently seeking additional representation from local service and helicopter airlines. Atthe same time, representatives of concerned governmentagencies are being invited to join the working group in anobserver, or associate member, status.

Purpose of the ATC System Planning Group is to determine what kind of air traffic control system will beneeded by 1975, and what steps have to be taken to getthere. The group's terms of reference call for an ATCsystem that can handle the growth of aviation with safetyand efficiency, a system which provides for changes, however radical, to be evolutionary, and caters to all usersof the airspace.

The ATA, a Corporation Member of IFATCA, is a service organization representing virtually all of the scheduled certificated airlines of the United States. It was organized in 1936 to se.rve the public and the government onbehalf of its member airlines in a wide range of activitiesfrom the improvement of safety to the planning for the airl i n e s ' r o l e i n n a t i o n a l d e f e n s e . A T A

Digital Air Traffic Control Training Simulatorf o r E U R O C O N T R O L I n s t i t u t eof Air Navigation Services Luxembourg

In late January, 1969, EUROCONTROL awarded a contract to Elliott Brothers (London) Ltd. worth 68 million Belgian Francs for the commissionning of an air traffic services training simulator in the Eurocontrol Institute of AirNavigation Services currently under construction in Luxembourg.

This complex computer-driven simulator will providethe new European Institute with a highly flexible and versatile tool for the advanced, specialist training of air traffic services personnel: controllers, programming staff andmaintenance engineers and technicians. Both the equipment and the computer prog.rammes have been so conceived as to ensure not only that training needs of themoment can be met but also the demands for the highlyspecialized personnel, made necessary by the ever increasing application of automated techniques in air traffic cont r o l .

Two Elliott 905 digital computers form the nucleus ofthe simulator as well as provide the means for an automated documentation centre for matters of air navigationsafety and related fields. The main computer will producethe simulated flight trajectories of, simultaneously, up to60 aircraft and their detection by two simulated primaryand secondary radar stations. The second computer willdrive the simulator's display system consisting of 22 electronic displays showing the processed air traffic data indynamic or tabulated form. These viewing units will beused as Controllers' and Pilots' positions, each equippedwith modern designation devices such as touch wire systems, light pens and dynamic keyboards.

An advanced telecommunication system to be installedby International Airadio Ltd. will provide the means tosimulate air/ground and ground/ground communications.

An important feature of the simulator's conception isthat six simulation exercises can be run simultaneously,giving the necessary capacity for the diversity of trainingthe Institute will have to provide.

The Institute will commence its theoretical trainingcourses in the Autumn of 1969 and the work of installingthe simulator is being phased in to meet the programmeof the progressive introduction of specialist training. Thesystem will be fully operational in early 1971 providing forthe most advanced operational and technical training ofair traffic services personnel from the Eurocontrol MemberStates and of those other States who may wish to availthemselves of the services of the Institute. EURO

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