Commander of Crashed Dash 8 Q400 in Nepal “Harboured Severe Mental Stress” Say Investigators

Posted by on Jan 28, 2019 in Accidents & Incidents, Fixed Wing, Human Factors / Performance, Safety Management | 0 comments

Commander of Crashed Dash 8 Q400 in Nepal “Harboured Severe Mental Stress” Say Investigators

US-Bangla Airlines flight 211, a Bombardier Dash 8 Q400 S2-AGU, crashed on landing at Kathmandu-Tribhuvan Airport, Nepal on 12 March 2018, resulting in the death of 51 of the 71 persons on board.

Wreckage of US-Bangla Airlines de Havilland Canada DHC-8-402Q Dash 8 S2-AGU at Kathmandu-Tribhuvan Airport (Credit: Nepal AIC)

Wreckage of US-Bangla Airlines de Havilland Canada DHC-8-402Q Dash 8 S2-AGU at Kathmandu-Tribhuvan Airport (Credit: Nepal AIC)

The Accident Investigation Commission’s final report, issued 27 January 2019, concluded:

The PIC who was also the pilot flying was under stress and emotionally disturbed as he felt that the female colleague of the company questioned his reputation as a good instructor.

This together with the failure on the part of both the crew to follow the standard operating procedure at the critical stage of the flight contributed to loss of situational awareness to appreciate the deviation of the aircraft from its intended radial that disabled them sighting the runway.

Having missed the runway and loss of situational awareness, the crew seemed to be orbiting at very low altitude with all EGPWS warning, at north of runway not realizing their correct position. This loss of situational awareness indulged the PIC into some dangerous maneuver of aircraft at very low altitude in the hilly and mountainous terrain around TIA. Finally, when the crew sighted the runway, they were very low and too close to runway 20 and not properly aligned with the runway.

For reasons unknown, probably in desperation to land, the PIC maneuvered the airplane in a very unsafe manner by forcing it to land while in a turn, with the right bank, at an angle of about 15 degrees with the RWY axis resulting the right main landing gear to make hard impact on the left of the centerline of runway 20, approximately 1700 meters from the threshold.

 

After impact on the ground the uncontrolled aircraft ran out of the runway, hit the runway perimeter fence and rolled down the slope into the grass field and caught fire which engulfed the aircraft.

On the flight crew among the investigators findings were:

  1. CVR recording revealed that the PIC Lacked adequate sleep the previous night prior to the flight.
  2. The PIC had operated to Kathmandu several times however the FO was operating this sector for the first time as an active crew.
  3. CVR and eyewitness account of the passenger confirm that PIC was smoking in the cockpit during the flight.
  4. Neither the pilots had practiced visual landing on RWY 20 in the simulator.
  5. The PIC was engaged in unnecessary, unprofessional and lengthy conversation even in critical phase of the flight. Thus, violating all norms of sterile cockpit.
  6. Steep crew gradient and higher authority of PIC probably prevented FO in assisting and being more assertive in significant phases of flight like approach and landing.
  7. The PIC did not provide his smoking habit and history of depression in the last medical self-declaration form.
  8. While teaching the FO, the PIC was very calm and professional but while talking about other issues he seemed emotionally disturbed.

On flight operations their findings were:

  1. It is evident that there were a number of SOP violations during the flight by the cockpit crew.
  2. International flight, especially to an airfield like KTM, was scheduled following four successive short domestic flights which shows poor operational planning.
  3. The flight crew had not been briefed about the recent requirement of Bangladesh ADC [Air Defence Clearance].
  4. Lack of proper co-ordination between the Dispatch and the crew regarding the preflight briefing which led to the PIC experiencing high level of stress, frustration and anger.
  5. A/C was not fully configured for landing over GURAS [the initial approach fix] which was contradictory to the company SOP.
  6. There was lack of clear communication between the crew members and also between crew members and ATC during the critical phases of flight.
  7. During the initial approach phase of flight, the aircraft was flown with autopilot on HDG mode with just 5 degrees of interception angle to intercept the final approach course of radial 202 degrees inbound to KTM VOR. But the VOR mode was never armed. Hence, the Autopilot flew the aircraft from left through the final approach path to right of the intended track. The high approach speed due to landing gears in retracted position made the deviation more pronounced.
  8. The aircraft reached the Minima about 1 NM offset with the Runway centerline path, but visual contact with the runway was not established due to low altitude and offset from final approach course. Thereafter, the crew were unable to locate the runway due to very low altitude on the downwind leg as well as they were on the northeast of the airfield with mountainous terrain.
  9. The ‘Heading made good’ distracted the pilot vision to establish visual contact with the runway.
  10. The lack of visual reference with the runway caused the crew to lose their situational awareness.
  11. The VOR Approach procedure for Kathmandu RWY 02 was never briefed and followed properly.
  12. A/C continued descent after Missed Approach Point instead of carrying Standard Missed Approach procedure.
  13. Though PIC communicated FO three green, the landing gears were not in extended position.
  14. Gear Unsafe tone and EGPWS warning continue but both the crew never noticed or neglected the warning.
  15. The loss of situational awareness hindered the consciousness of PIC to execute a ‘goaround’ to gain altitude for wider vision and better ground orientation at any time during the conduct of visual flight at low heights.
  16. The situational awareness having lost, the aircraft was flown manually in both vertical and horizontal planes at very low height with abnormally variable speeds and bank angles.
  17. PIC had realized his mistake of talking a lot during the critical phases of flight.
  18. During the final phase of the visual landing, the aircraft was flown manually at a very close proximity of the runway with high-angle bank of approximately 30 degrees in order to align with the Runway.
  19. Considerable amount of centrifugal force persisted at this time due to high degree of bank angle, rapid descent rate and excessive threshold speed with apparently inadequate inner rudder input to generate sufficient centripetal force as a counter measure to centrifugal force.
  20. Circumstantially, the aircraft made one outer main wheel hard contact with the runway and thereafter skidded out of the runway before catching fire.
  21. The accident occurred during a visual landing phase of flight under the control of the PIC, who seemed to be unaware of the danger until it was too late.

They go on to discuss medical and human factors issues, including:

  1. The PIC was declared unfit to fly in 1993 due to his medical condition (depression). He was later cleared medically only in 2002.
  2. Medical examination of PIC in successive annual medical was not focused on his previous medical condition of Depression; which seemed mandatory. This may have been missed as this was not declared in self-declaration form in annual medicals.
  3. There was no evidence that the pilot suffered any sudden illness or incapacitation which might have affected his/her ability to control the aircraft.
  4. Toxicological analysis was Negative for Insecticides, Narcotic drugs, Ethyl alcohol, and Methyl alcohol and Phosphine gas. However the toxicology testing did not include prescription medications that are commonly used to treat depression (e.g., anti-depressants) or anxiety (e.g., benzodiazepines, anxiolytics).
  5. There is clear evidence that PIC was harboring severe mental stress. The effect of stress was evident with the fact that he was irritable, tensed, moody, and aggressive at various times. This is probably the reason for his undue aggressive behavior and anger aimed at ATC personnel as well as operation staff.
  6. The foul language and abusive words he was using in conversation with a junior female FO was very inappropriate and certainly not expected from a level headed person.
  7. PIC also seemed to be fatigued and tired due to lack of sleep the previous night as well as due to the stress he was harboring.
  8. PIC seemed very unsecure about his future as he had submitted resignation from this company, though only verbally. He said he did not have any job and did not know what he was going to do for living. The financial insecurity may have augmented his stress.
  9. FO asked PIC about Missed Approach Procedure of Kathmandu but PIC never briefed her, rather got engaged in unnecessary and personal talks. Failure to react after missing the runway for the first time, not doing standard go around procedures after missing the Missed Approach Point (MAP) and impaired decision making; all were probably due to stress.
  10. The PIC seemed to have loss of situational awareness. He did not realize that they had crossed VOR and was under impression that they are still behind it.
  11. Even in the last moments of flight, PIC had fixation to land at any cost and he never considered for go around procedure even after realizing that flight was not configured to land. One of the reasons could be him trying to prove FO that he is a very competent pilot and would be able to safely land the aircraft in any adverse situation.

There are further findings which we have not reproduced here.

The AIC Probable Cause and Contributing Factors

The Accident Investigation Commission determines that the probable cause of the accident is due to disorientation and a complete loss of situational awareness in the part of crewmember.
Contributing to this the aircraft was offset to the proper approach path that led to maneuvers in a very dangerous and unsafe attitude to align with the runway. Landing was completed in a sheer desperation after sighting the runway, at very close proximity and very low altitude. There was no attempt made to carry out a go around, when a go around seemed possible until the last instant before touchdown on the runway.

Contributing Factors:
a. Improper timing of the pre-flight briefing and the commencement of the flight departure in which the operational pre-flight briefing was given in early morning but the flight departure time was around noon and there were four domestic short flights scheduled in between.
b. The PIC, who was the pilot flying, seemed to be under stress due to behavior of a particular female colleague in the company and lack of sleep the preceding night.
c. A very steep gradient between the crew.
d. Flight crew not having practiced visual approach for runway 20 in the simulator.
e. A poor CRM between the crew.

AIC Safety Recommendations

To the CAA Bangladesh (the air operator’s regulator):

  1. Before the renewal of license of any permanently grounded pilot due medical reason, a thorough periodic physical and psychological status should be assessed. A system should be adopted so as to monitor the medical condition closely in all subsequent medical examination as well.
  2. Commission recommends that all airline pilots should undergo psychological evaluation as part of the training or before entering into the service. The airline shall verify that the evaluation has been carried out. The psychological part of the initial and recurrent aeromedical assessment and the related training for the aeromedical examiners should be strengthened.

To the air operator:

  1. …give emphasis to the proper and effective implementation of CRM in the company.
  2. …establish a system to ensure the proper implementation of SOP in all phases of flight.
  3. …establish an effective mechanism to monitor and assess mental status of the crew in regards to profession development, financial issues as well as personal and psychological issues.
  4. …establish and implement a policy to de-roster any crew member found to be stressed, fatigued or emotionally disturbed.
  5. …reexamine its system to ensure that all the relevant documents are timely reviewed and updated.
  6. …revise their training process to include circling approach for RWY 20 Kathmandu on the simulator.
  7. …reassess its preflight briefing to ensure that a proper pre-flight briefing to the crew by the dispatcher has been conducted at the appropriate time.
  8. …revise their training process to include provision of safety pilot during KTM Route clearance training for less experienced pilots.
  9. …ensure that Line Oriented Safety Audit (LOSA) should be carried out periodically.The operator should encourage the crew members to be specific regarding their medical issues and habits in the medical self-declaration form.
  10. …reinforce firm policy regarding No Smoking in the flight and have a system in place to monitor it proactively and take actions accordingly.

To CAA Nepal:

  1. CAAN should strengthen the capacity of the ATCs, by developing the appropriate training programme so that they become more assertive when handling the traffic and issuing clearances to such traffic especially in the event of the abnormal or emergency situations.
  2. The ATC to be more vigilant and shall visually look out for the aircraft after the landing clearance has been issued in VMC.

Other Safety Resources

This is not a fundamentally new problem in aviation.  On 30 October 1959 DC-3 N55V of Piedmont Airlines crashed at Bucks Elbow Mountain, Virginia, killing 26 of the 27 occupants.  Investigators of the Civil Aeronautics Board (CAB), forerunner to the NTSB, found the Aircraft Commander had suffered from “serious emotional and mental stress episodes since 1953. He was under psychotherapy at the time of the accident” and ” likely taking Prozine in the period leading up to the accident, an antipsychotic medicine”.  The CAB stated that the investigation “demonstrated the need for re-examination of the use of drugs that might affect the capabilities of a flight crew member” and “if a flight crew member’s personal situation demands tranquilizers he should be removed from flying status while on the drugs.”

See also:

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