NTSB Accident Investigations

Transcription

1 NTSB Accident Investigations Captain Ben Berman George Mason University April 4, 2016 S

2 Carbon on the mountain S December 22, 1996

3 Carbon on the mountain S December 22, 1996 S Airborne Express 827

4 Carbon on the mountain S December 22, 1996 S Airborne Express 827 S Killed 5 pilots/techs

5 Carbon on the mountain S December 22, 1996 S Airborne Express 827 S What could have brought a DC-8 down?

6 Carbon on the mountain S December 22, 1996 S Airborne Express 827 S What could have brought a DC-8 down?

7 Carbon on the mountain S What could have brought a DC-8 down?

8 Carbon on the mountain S What could have brought a DC-8 down? S What am I doing here?

9 My path to that mountain, and after

10 About the NTSB S Roots S Independence S Probable Cause S Annex 13

11 About the NTSB S Party system S A fact is a squirrely thing S Sunshine process S Outputs S Bluecover reports S Safety recommendations

12 NTSB Investigation of ABX 827 S My role: operations investigation and overall analysis S Proximate cause: Flying too slowly S But S Factors underlying this simple accident

13 History of the Flight S S S S S S S Planned Functional Evaluation Flight after major maintenance Departed late due to mechanical issues Darkness and cloud layers Test card required evaluation of stall warning system 14,000 feet just on top, slowed at 1 knot per second Buffet at 151 knots, That s a stall right there, ain t no shaker. Steep descent and 1:32 later crash into the mountains at 240 knots

14 History of the Flight S Proximate cause: Flying too slowly S But factors underlying this simple accident S One Pager, Learjet ride and ATV ride later

15 On Scene Investigation S Flight deck documentation: not much to see S Impact angle and attitude from tree breaks S Four corners found, engines ate dirt S Flight data recorder: 11 parameter unit S Cockpit voice recorder: 30 minute tape loop

16 Wilmington Investigation S Pilot background and experience S PM: USAF, Flight manager, examiner, instructor, 463 hours in T/P S PF: Flight manager, instructor, 434 hours in T/P S FEF experience: PM SIC, no stalls; PF no prior S Simulator evaluation and fidelity S Previous incident and FEF/stall procedures evaluation

17 Laboratory Investigation S CVR readout and transcript: inside the chamber S FDR readout S Vehicle performance study: Inferences (few parameters) and implications S Video re-creation of accident sequence

18 CVR Review

19 CVR Review

20 CVR Review

21 Vehicle Performance Study Let s do one!

22 Organizational factors/corporate culture S Director of flight technical programs S Training of FEF pilots S Previous incident and stall procedure change S Reversion to previous procedure: We don t need that. S Pressures to perform

23 Accident Analysis S Now we know what happened so why did it happen? S Engines S Aircraft S Stall was intentional, so how did they not know?

24 Accident Analysis S How does a pilot know the aircraft is stalled? S How does a pilot know the aircraft is unstalled? S Stall vs. Nose-low, high speed roll upset S Role of distraction (engine, rolling moments) S Experience positive and negative (simulator)

25 Accident Analysis S Procedures and procedural change S Risk factors (night, cloud ) S Cognitive biases

26 Accident Analysis S Procedures and procedural change S Risk factors (night, cloud ) S Cognitive biases S Plan continuation

27 Accident Analysis S Procedures and procedural change S Risk factors (night, cloud ) S Cognitive biases S Plan continuation S Expectations

28 Accident Analysis S Procedures and procedural change S Risk factors (night, cloud ) S Cognitive biases S Plan continuation S Expectations S Confirmation

29 Accident Analysis S Procedures and procedural change S Risk factors (night, cloud ) S Cognitive biases S Plan continuation S Expectations S Confirmation

30 Accident Analysis S Was this crew deficient?

31 Accident Analysis S Was this crew deficient? S Back pressure inputs

32 Accident Analysis S Was this crew deficient? S Back pressure inputs S Own own bias

33 Accident Analysis S Was this air carrier deficient? S Safety management/improvement process S Risk evaluation in test flight program S Weather/lighting S Crew pairing S I do the flying

34 The Probable Cause

35 Corporate aftermath of ABX 827 S Millions of dollars in losses (billions) S Managers tied up with litigation for years S Managers on my team all lost their jobs S Company no longer exists (remnant now belongs to Amazon.com)

36 Safety results of the accident S What would you recommend?

37 Safety results of the accident

38 Safety results of the accident S Has this happened again???? (Sigh )

39 Thanks very much! Questions/Com ments Welcome Here