nm top 5 safety priorities - flight safety foundation · asmgcs unserviceable. the b737 crew saw...

NM Top 5 Safety Priorities

Tzvetomir BLAJEV

A Serious Incident Analysis

A conditional clearance

“Behind next landing short

final, line up 07 behind”.

Correct readback.

No reference that A321 to

take-off before.

B737 is given clearance to

land and ATR42 begins to

move onto rwy via a RET.

ATC did not see the ATR42

until the pass was taking place.

ASMGCS unserviceable.

The B737 crew saw late.

Crash narrowly missed.

What factors were involved?

1. Convey incomplete

information.

2. Plan – clearance not relative

to the next movement.

3. Risky procedure – use of

RET with no line of sight.

4. Perception/detection ATC.

5. Airport systems.

6. Perception/detection Crew

7. Providence

A conditional clearance

“Behind next landing short

final, line up 07 behind”.

Correct readback.

No reference - the A321 to

take-off before.

B737 is given clearance to

land and ATR42 begins to

move onto rwy via a RET.

ATC did not see the ATR42

until the pass was taking place.

ASMGCS unserviceable.

The B737 crew saw late.

Crash narrowly missed.

Counting factors is not Grasping reasons!

1. Convey incomplete information.

2. Plan.

3. Risky procedure.

4. Perception/detection ATC.

5. Airport systems.

6. Perception/detection Crew

7. Providence

How to get the safety priorities then?

EXPERTISE - Develop an approach based on explicit

safety control functions and not on counting factors.

DATA - Use a robust data set to see what safety

function works and what safety function fails.

KNOWLEDGE - Peer group review of the data to make

sense of the success and failure and decide on the

priorities.

Basic Barriers: Runway Collision

PREVENTING RUNWAY INCURSION

ATC PREVENTING RUNWAY CONFLICT

ATC RUNWAY COLLISION AVOIDANCE

PILOT / DRIVER RUNWAY COLLISION AVOIDANCE

PROVIDENCE

RUNWAY INCURSION

UNRESOLVED BY ATC RUNWAY CONFLICT

UNRESOLVED BY PILOT / DRIVER RUNWAY CONFLICT

RUNWAY CONFLICT

ZOOM – Preventing Runway Incursion





PROVIDENCE

RUNWAY INCURSION

UNRESOLVED BY ATC RUNWAY CONFLICT

UNRESOLVED BY PILOT / DRIVER RUNWAY CONFLICT

RUNWAY CONFLICT

Level 1 Barriers Zoom

Preventing

ATC to cause

incorrect

entry of

taxiing

mobile

Preventing

taxiing

pilot/driver to

cause an

incorrect

entry

Preventing

incorrect

presence of

vacating

mobile

Preventing

incorrect

presence of

landing

aircraft

Preventing

incorrect

presence of

taking-off

aircraft

Preventing

incorrect

presence of

person



ATC Traffic

Awareness

ATC Traffic

Plan

ATC

Coordination

ATC Plan

Execution

Error Detection and Resolution


PREVENTING ATC TO CAUSE

INCORRECT ENTRY OF TAXIING MOBILE



PREVENTING ATC TO CAUSE

INCORRECT ENTRY OF TAXIING MOBILE

ATC TRAFFIC PLAN EXECUTION

INCOMPLETE

INFORMATION IN THE

CONDITIONAL

CLEARANCE




DATA - Use a robust data set to see what safety function

works and what safety function fails.



priorities.

Data Gathering

Workshops with European Air Navigation Service Providers.

Data for their most serious incidents for one year.

Representative sample.

Sample to population representativeness

ALL PHASES ‘A’ AND ‘B’ SEPARATION

MINUMA INFRINGEMENTS 264

ANALYSED

EN-ROUTE

INCIDENTS

ALL ‘A’ AND ‘B’ RUNWAY

INCURSIONS

ANALYSED

RUNWAY

INCURSIONS

101

Participation

of 14 ANSPs

Geographical representativeness

22 Taxiing mobile

incorrectly

entering

8* ATC causing an

incorrect entry of

taxing mobile

3 conflicting take-off clearance

1 incorrect take off after air-ground communication

8 ATC not providing

correct and timely

landing clearance

7 landing without clearance

4 insufficient spacing

4 incorrect presence of vacating aircraft

* 1 event was a prevented runway incursion

Runway Incursion: The scenario trigger

PROVIDENCE




56


11

WORKED OR NOT NEEDED

45

14 31

28 3

3

FAILED

1

How many times a barrier failed and worked?





PROVIDENCE

1

11

14

28

3

How many incidents are stopped by a barrier?





PROVIDENCE

0

0

1

9

2

Sudden High Energy Runway Conflict

PREVENTING TACTICAL CONFLICT

ATC TACTICAL SEPARATION ASSURANCE

ATC COLLISON AVOIDANCE

PILOT COLLISION AVOIDANCE - ACAS

PILOT COLLISION AVOIDANCE - VISUAL

PROVIDENCE

POTENTIAL AIRBORNE (TACTICAL) CONFLICT

POTENTIAL COLISION UNRESOLVED BY ATC

POTENIAL COLISION UNRESOLVED BY ACAS

LOSS OF SEPARATION

POTENIAL COLISION UNRESOLVED BY PILOT

Basic Barriers: Separation minima infringement en-route

30 Blind Spot

13 Sector coordination

10 ATCO controlling technique

8 altitude deviation

8 pre-tactical conflicts

7 military activity

6 Air-ground communication

4 vertical speed deviation

4 executive plan of work

2 ATCO execution

1 Overlooked aircraft

1 Airspace infringement

1 Lateral deviation

Separation infringement – The scenario trigger

PROVIDENCE

PILOT COLLISION AVOIDANCE -ACAS

ATC COLLISION AVOIDANCE

ATC SEPARATION ASSURANCE 95


PILOT COLLISION AVOIDANCE -VISUAL

55 44

41 3

1 2

2

FAILED

95

WORKED OR NOT NEEDED

How many times a barrier failed and worked?






PROVIDENCE

51

41

1

2

How many incidents are stopped by a barrier?

19






PROVIDENCE

BLINDSPOT

11

SECTOR COORDINATION

ACAS RA NOT FOLLOWED

TRANSPONDER FAILURE

Reported additionally to the

study sample

Does the incident scenario make a difference?

From a representative sample of EVAIR

automatic Mode S monitoring (2010-2014)

Excessive3%

Followed64%

Below required

rate15%

Opposite18%

Pilot responses to initial RAs Pilot responses to secondary RAs

Excessive5%

Followed75%

Below required

rate12%

Opposite8%

95

55 44

41 3

1 2

2

95 56

11 45

14 31

28 3

3

1

FAILED WORKED OR NOT NEEDED

Separation Infringement En-Route Runway Incursion

Big proportion ‘ saved’

by the last available

barriers

How protected we are?

Separation infringements vs. Runway Incursions








priorities.

The suggested Top 5 safety priorities

• A single threat often removing

all the barriers up to ‘see and

avoid’;

• No ATC awareness;

• No STCA;

• No TCAS/ACAS.

Risk of operation without transponder or with a

dysfunctional one

• The associated risk is extremely

high;

• No ATC control;

• Often the providence is the only

available barrier;

ACAS RA not followed

• Conflict was not detected with the

closest aircraft;

• Often after descending clearance;

• Majority are triggered by sector

exit constraints or rushed

clearance after a pilot request

• Rapidly developing situation –

often 1000ft and 15 Nm between

the conflicting a/c.

Blind Spot

• Good share of the severe Runway

Incursion incidents could have

been prevented;

• Need for the controllers to detect

that the runway was occupied at

the time of giving a clearance for

the next aircraft to use it.

Controller detection of potential runway conflict

• Typically involves rapidly

developing situation

• Runway entry in front of a high

energy landing or taking-of aircraft

• At position where the available

reaction time is close to or less

than the needed reaction time

for detection, communication and

collision avoidance manoeuvre

Sudden High Energy Runway Conflict

In Summary







priorities.

nm top 5 safety priorities - flight safety foundation · asmgcs unserviceable. the b737 crew saw...

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