Safety Investigation into the accident to the Airbus A330, Air France flight 447, June 1, 2009 Human Factors Issues Sébastien DAVID, Senior Safety Investigator Head of the Human Factors working group

June 2009 Investigation working groups - Sea searches - Systems - Operations - Maintenance June 2011 June rd Interim report Flight Recorders Recovery Human Factors Working group AF447 Human Factors Group – Overview June st Interim report FINAL REPORT 2nd Interim report

AF447 Human Factors Group – Overview  Organization Initiation of HF investigation: - August 2011, after the release of the third interim report Constitution: - Four experts (HF, pilots…) - Three BEA investigators Coordination - Close coordination with IIC and other working group leaders  Group report BEA internal document - Used for the Final Report - Same format as BEA reports (based on the one recommended by ICAO Annex 13)

Human Factors Group - Objectives and Methodology 1.To explain safety measures supposed to ensure flight safety in similar operational situations

Human Factors Group - Objectives and Methodology 1.To explain safety measures supposed to ensure flight safety in similar operational situations 2.To analyse the performance of those safety measures for the investigated situation

Human Factors Group - Objectives and Methodology  Example of Fatigue Investigation  Part in the Final Report « Aspects relating to fatigue »  Two steps:  Fatigue estimation Sleep aspects (length, quality…) Circadian factors Awakening  Evaluation of pilots performance, behaviors

Human Factors Group - Objectives and Methodology  Example of Fatigue Investigation  Fatigue estimation Limitations on flight and duty times, as well as rest time  in accordance with EC n°859/2008 Accident happened between midnight and 06h00  Circadian dip Awakening and sleep: Lack of precise information Impossible to evaluate accurately the level of fatigue of the crew

Human Factors Group - Objectives and Methodology  Example of Fatigue Investigation  Evaluation of pilots performance, behaviors Based on CVR recording Level of activity and implication of the augmented crew  Vigilant attention No signs of drowsiness or sleepiness Fatigue management  Captain’s questions No evidence of performance or behaviors consistent with effects of fatigue or sleepiness prior to the accident

Human Factors Group - Objectives and Methodology 1.To explain safety measures supposed to ensure flight safety in similar operational situations 2.To analyse the performance of those safety measures for the investigated situation 3.To make an evaluation of the rationality and the robustness of those safety measures

Human Factors Group - Objectives and Methodology 1.To explain safety measures supposed to ensure flight safety in similar operational situations 2.To analyse the performance of those safety measures for the investigated situation 3.To make an evaluation of the rationality and the robustness of those safety measures 4.To make recommandations

AF447 Human Factors Group – Analysis 1.From the cruise to the AP disconnection A. Cruise and crossing the ITCZ: perception and management of operational risk B.Relief of Captain 2.From the AP disconnection to triggering of stall warning A. Detection of problem B. Control of flight path C. Identification of the situation D.Attempt to control the flight path E.Return to handling the failure 3. After triggering of stall warning A.Piloting inputs B.Return of Captain C.End of HF analysis

AF447 Human Factors Group – Analysis 1.From the cruise to the AP disconnection A. Cruise and crossing the ITCZ: perception and management of operational risk B.Relief of Captain 2.From the AP disconnection to triggering of stall warning A. D ETECTION OF PROBLEM B. Control of flight path C. Identification of the situation D.Attempt to control the flight path E.Return to handling the failure 3. After triggering of stall warning A.Piloting inputs B.Return of Captain C.End of HF analysis

Detection of a problem – The context  What was (is) known about the sequence of events:  Temporary inconsistency between the measured speeds, likely following obstruction of the pitot probes by ice crystals Ice Crystals Measured Pressure  Autopilot disconnection  Reconfiguration to alternate law

Detection of a problem – The HF approach  What was used in the frame of the HF analysis:  Available data put in the context of the crew  Safety expectations in case of a sudden anomaly and implications on human performance  For a good chance that these expectations of the crew may be met, necessity to have: - the signs of the problem sufficiently salient - these signs credible and relevant - the available indications relating to the anomaly swiftly identifiable - actions sufficiently rehearsed to be associated with awareness of the anomaly - no signals or information available that suggest different actions 1.To control the flight path 2.To detect the anomaly 3.To « make sense » of this anomaly 4.To take corresponding actions and decisions

Detection of a problem – The HF approach  What was used in the frame of the HF analysis:  Case of speed anomalies 1.To control the flight path 2.To identify the loss of consistency in indicated airspeed 3.To « make sense » of this anomaly 4.To manage the anomaly with:

Detection of a problem – The HF approach  Samples of how it was analysed by the HF group:  Salience of the speed anomaly very low compared to that of the autopilot disconnection  Reaction of the crew by taking over manual control ⇒ No idea of why the AP disconnected ⇒ Surprise of the pilots due to the new situation  No definition of the flight path to follow ⇒ Large input on the PF sidestick  Identification of a speed indication anomaly ⇒ No call out of the procedure ⇒ No correlation between the loss of displayed speeds and the associated procedure  Absence of a constructed action plan ⇒ Reactive management of the situation Not specific to this crew

Findings  Training  Basic Airmanship  Human – Machine Interactions  CRM  Stress  Procedures Inputs for Safety Recommendations AF447 Human Factors Group - Conclusions