Research to Reality in Air Traffic Management

BENEFITS ASSESSMENT OF REDUCED SEPARATIONS IN NORTH ATLANTIC

ORGANIZED TRACK SYSTEM

August 2005

Almira Williams, CSSIIsrael Greenfeld, NASA Glenn

2

Project Objective

• Determine benefits of reduced horizontal separations in the North Atlantic Track System as a function of equipage levels and demand growth for up to 2015

• Determine improvements in flight efficiency through metrics such as fuel and time cost savings, and additional cargo revenue potential (by flight and by airframe)

• Determine improvements in system performance through metrics such as approved alt. change requests, and duration at sub-optimal altitude

3

Project Scenarios

• Three Demand levels: 2005, 2010, and 2015

• Five Equipage levels: 0, 25, 50, 75, and 100

• 2 sets of tracks: early morning eastbound (V-Z) and early afternoon westbound tracks (A-F).

• Three types of track configuration: - Regular: current tracks with mixed equipage operations

- Segregated: some tracks not accessible to non-equipped flights

- Additional Segregated: new tracks established between two adjacent segregated tracks

=> 72 simulation scenarios (+9)

4

Modeling Requirements

• Future traffic generator to determine traffic demand levels, and fleet and equipage for the future years of interest

• Fuel consumption optimization model to determine optimal trajectories, step-climb and speed profiles for each of the flights (ISO atmosphere and forecasted wind data)

• Track selection model to determine user-preferred tracks for the future flights

• Track operations simulation models to impose restrictions due totraffic interactions (modify optimal altitude and speed profiles)

• Fuel consumption model to determine fuel requirements for the constrained trajectories

5

Benefits Mechanisms

6

Benefits Mechanisms

- Improved routes, altitude and speed profiles• Lower fuel consumption• Shorter flight times• Additional cargo potential

- Improved ability to estimate fuel requirements • Contingency fuel reduction• Improved schedules• Additional cargo potential

- Improved system performance• Accommodation of higher demand levels, accommodation of user preferred

choices, including denied alt. change requests, duration at sub-optimal altitude, etc.

7

Benefits Mechanisms:Current Practices in NAT OTS

Each flight is required to maintain its track, altitude and Mach number, as assigned by the oceanic ATSP.

LateralSeparation

Longitudinal Separation

Track A

Track B

Track C

Track D

Track C

LongitudinalSeparation

Vertical Separation

Cruise climb

Step climb

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Benefits Mechanisms due toSeparations Reduction

Track A

Track B

Track C

Track D

Track C

Separations affect both spatial and temporal distribution of flights within the track system

30 NM 30 NM50 NM 50 NM

30 NM 30 NM50 NM 50 NM

Flight A

40 NM

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Benefits Calculations:Regular Tracks

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Assumptions Summary• Flights cannot switch tracks once they entered the track system

• Traffic is conducted independently on each track

• Longitudinal separations: 30NM between two equipped flights, and 10 minutes Mach technique (~ 80 NM) otherwise

• 6-hour wind forecasts and ISO atmosphere

• Cost Index values are determined for each of the aircraft models

• Each flight takes off with MTOW

• Unit fuel cost: $1.39/gallon ($0.21/lb), and unit cargo revenue: $1.60/lb

• Fuel and Time Cost Savings and Cargo Revenue Potential can be negative (penalties)

11

NAT OTS – Equipage Considerations

Equipped flights can climb throughout their flights, whereas the non-equipped flights cannot climb while on NATOTS

320

330

340

350

360

2 4 6 8 10 12 14 16

GMT (hr)

Non-equipped Flight

Equipped Flight

Track Segment

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Regular Tracks: Average Fuel and Time Savings (per flight)

$0

$40

$80

$120

$160

$200

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

. Fue

l and

Ti

me

Savi

ngs

($)

200520102015

13

Regular Tracks – Fuel and Time Savings: Benefits vs. Penalties

0%10%

20%30%

40%50%

60%70%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent F

light

s w

/Ben

efits

0%

10%

20%

30%

40%

50%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent F

light

s w

/Pen

altie

s

$0

$50

$100

$150$200

$250

$300

$350

0% 25% 50% 75% 100%

Equipage Level (%)

Ave

rage

Ben

efits

($)

-$120

-$100

-$80

-$60

-$40

-$20

$00% 25% 50% 75% 100%

Equipage Level (%)

Ave

rage

Pen

altie

s ($

)

2005

2010

2015

14

Regular Tracks – Fuel and Time Savings: Equipped vs. Non-equipped Flights

0%

20%

40%

60%

80%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent P

enal

ized

-N

on-E

quip

ped

Flig

hts

(%)

0%

20%

40%

60%

80%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent P

enal

ized

-Eq

uipp

ed F

light

s (%

)

0%

20%

40%

60%

80%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent B

enef

ited

-N

on-E

quip

ped

Flig

hts

(%) 2005

2010

2015

c

0%

20%

40%

60%

80%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent B

enef

ited

-Eq

uipp

ed F

light

s (%

)

0%

25%

50%

75%

100%

0% 25% 50% 75% 100%

Equipage Level (%)

Perc

ent U

ncha

nged

-N

on-E

quip

ped

Flig

hts

(%)

0%

5%

10%

15%

20%

0% 25% 50% 75% 100%

Equipage Level (%)

Per

cent

Unc

hang

ed -

Equ

ippe

d Fl

ight

s (%

)

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Regular Tracks: Equipped vs. Non-equipped Flights (cont.)

0.0%

0.1%

0.2%

0.3%

0.4%

0.5%

0% 25% 50% 75% 100%

Equipage Level (%)A

vera

ge S

avin

gs p

er

Non

-equ

ippe

d Fl

ight

(%)

2005

2010

2015

0.0%

0.1%

0.2%

0.3%

0.4%

0.5%

0% 25% 50% 75% 100%

Equipage Level (%)

Ave

rage

Sav

ings

per

Equi

pped

Flig

ht (%

)

16

Regular Tracks: Total Annual Benefits

25% 50% 75% 100% 25% 50% 75% 100% 25% 50% 75% 100%

Total Annual Fuel And Time Benefits

4 M$ 9 M$ 12 M$ 14 M$ 13 M$ 19 M$ 29 M$ 31 M$ 26 M$ 41 M$ 52 M$ 60 M$

Total Annual Add.Fuel Benefits 3 M$ 7 M$ 11 M$ 12 M$ 10 M$ 14 M$ 18 M$ 19 M$ 19 M$ 30 M$ 40 M$ 47 M$

Total Annual Benefits 7 M$ 16 M$ 23 M$ 27 M$ 23 M$ 34 M$ 47 M$ 51 M$ 46 M$ 72 M$ 92 M$ 106 M$

2005 2010 2015

• If operators do not want to carry extra cargo, but want to take maximum advantage of potential fuel savings instead, the total annual benefits system-wide are …

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Regular Tracks: Total Annual Benefits (cont.)

25% 50% 75% 100% 25% 50% 75% 100% 25% 50% 75% 100%

Daily Fuel andTime Savings 11 K$ 24 K$ 33 K$ 40 K$ 36 K$ 53 K$ 79 K$ 86 K$ 72 K$ 113 K$ 143 K$ 163 K$

Daily Add.Cargo Revenue 87 K$ 189 K$ 276 K$ 325 K$ 253 K$ 390 K$ 608 K$ 674 K$ 512 K$ 802 K$ 1,062 K$ 1,239 K$

Total DailyBenefits 99 K$ 214 K$ 309 K$ 365 K$ 289 K$ 443 K$ 686 K$ 759 K$ 584 K$ 914 K$ 1,205 K$ 1,402 K$

Total Annual Benefits 36 M$ 78 M$ 113 M$ 133 M$ 106 M$ 162 M$ 251 M$ 277 M$ 213 M$ 334 M$ 440 M$ 512 M$

2010 20152005

• If operators do want to carry extra cargo, the total annual benefits will be 4.7 to 5.5 time higher!

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Benefits Calculations: Segregated and Additional Segregated Tracks

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Assumptions

• Segregated Tracks are chosen based on:- Preferences of the equipped flights- Equipage level: 25% equipage - one, 50% equipage – two, and

75% equipage three segregated tracks• Potential candidates for segregated tracks do not include

outside tracks • Additional tracks can be established only between two

adjacent segregated tracks

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Average Fuel and TimeSavings Comparison (per flight)

2015

$0

$50

$100

$150

$200

0% 25% 50% 75% 100%Equipage Level (%)

Avg

Fue

l and

Tim

e S

avin

gs ($

)

2010

$0

$50

$100

$150

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

Fue

l and

Tim

e S

avin

gs ($

)

2005

$0

$50

$100

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

Fue

l and

Tim

e S

avin

gs ($

)

RegularSegregatedAdd.Segr.

2015

$0

$500

$1,000

$1,500

$2,000

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

Add

Car

goR

even

ue ($

)

2010

$0

$500

$1,000

$1,500

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

Add

Car

go

Rev

enue

($)

2005

$0

$500

$1,000

0% 25% 50% 75% 100%

Equipage Level (%)

Avg

Add

Car

go

Rev

enue

($)

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Sensitivity of Benefits to Segregated Track Selection

Fuel & Time Savings: Equipped Flights

-50

0

50

100

150

200

W X Y

Designated Track

Avg

. Sav

ings

($)

Fuel & Time Savings: All Flights

-50

0

50

100

150

200

W X Y

Designated Track

Avg

. Sav

ings

($)

2005

2010

2015

• 9 test scenarios- 25% equipage level- One segregated track (candidates: inside tracks)- Eastbound tracks early morning tracks

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Conclusions

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25% 50% 75% 100% 25% 50% 75% 100% 25% 50% 75% 100%

Regular Tracks 36 M$ 78 M$ 113 M$ 133 M$ 106 M$ 162 M$ 251 M$ 277 M$ 213 M$ 334 M$ 440 M$ 512 M$

Segregated Tracks 8 M$ 62 M$ 91 M$ 45 M$ 146 M$ 205 M$ 139 M$ 353 M$ 413 M$

Additional Segregated Tracks 71 M$ 105 M$ 151 M$ 160 M$ 233 M$ 300 M$ 354 M$ 459 M$ 569 M$

2005 2010 2015

Conclusions

• Yes, both equipped and non-equipped flights will benefit

• Equipped flights are 2-5 times more likely to experience savings than non-equipped flights, and on average save 1.5-4.6 times more

• The sooner an air carrier equips its fleet, the better off it will be (provided that sufficient overall equipage is reached)

• Designating certain tracks for exclusive use by equipped flights is controversial and will require careful examination

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Additional Slides

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System Performance Metrics SummaryRegular Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Perc

ent o

f Alt

Cha

nge

Req

uest

s G

rant

ed

Segregated Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Perc

ent o

f Alt

Cha

nge

Req

uest

s G

rant

ed

Additional Segregated Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Perc

ent o

f Alt

Cha

nge

Req

uest

s G

rant

ed

Regular Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Perc

ent o

f Tim

e A

tO

ptim

al F

light

Lev

el

200520102015

Segregated Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Per

cent

of T

ime

At

Opt

imal

Flig

ht L

evel

Additional Segregated Tracks

81%

84%

87%

90%

93%

96%

0% 25% 50% 75% 100%

Perc

ent o

f Tim

e A

tO

ptim

al F

light

Lev

el

26

NAT OTS Baseline Traffic DataAB

ZYXWV

FEDC

GANDER OCEANIC FIR SHANWICK OCA

SONDRESTROM FIR REYKJAVIK FIR

SANTA MARIA OCANEW YORK (MNPS)

0%

5%

10%

15%

20%

25%

30%

V W X Y Z A B C D E F

Eastbound tracks[1:00-8:00 GMT]

Westbound tracks[11:30-19:00 GMT]

ADS: 27%

Datalink: 34%

RNP: 99%

Scheduled: 88%

Non-sch.: 6%

Military: 2%

GA: 2%

Cargo:1%

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NAT Traffic Growth Parameters• Average annual growth rate

– Scheduled: 4.5%– Cargo: 4.3%– GA: 3.7%– Non-scheduled: 2.68%– Military: -1.95%

• Overall traffic growth rate– 7.6% by 2005– 30.4% by 2010 – 58.9% by 2015

• Equipage assumptions– New airframes enter the system

already equipped– Newer models are equipped

before old 5%3%--B7876%3%--A3801%1%1%1%

CL60/CL64

1%1%1%1%GLF4--1%1%DC10--2%2%MD11

3%3%3%3%B7577%7%8%7%A3408%12%13%14%B747

17%16%15%15%A33022%22%19%19%B77729%30%33%32%B767

2015201020052004

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Equipage Assumptions

100%100%-100%100%-100%100%-GLF4

100%--100%--100%--CL60/CL64

100%100%100%100%100%100%---B7E7

100%60%40%100%100%50%100%100%75%B777-300

75%60%40%75%75%50%100%100%75%B777-200

75%25%-75%25%-75%25%-B767-300/400

30%--30%--30%--B757-200

75%70%33%100%75%50%100%75%50%B747-400

100%100%100%100%100%100%---A380

75%100%100%100%100%100%100%100%100%A340-500/600

75%60%40%100%75%50%100%100%75%A340-300

75%50%-75%50%-100%50%-A330-200/300

75%50%25%75%50%25%75%50%25%AC Type

2015 Overall Equipage2010 Overall Equipage2005 Overall Equipage