The captain's inputs were not consistent with pilot training or reaction to a stall warning, but were consistent with surprise and confusion. The captain had a history of failing simulator training sessions.
Earlier in his career the captain had received training on the Saab 340, which is susceptible to tail plane stall and provides a stick pusher. This may have led the captain to believe, the Dash 8 was suscecptible to tail plane stall.
Training at Colgan complied with industry standards but did not require to include training of recovery from a fully developed stall, did not include the element of surprise, autopilot disconnect or the increased stall speed setting (icing).
The civilian pilot certification just states, that a test was passed, however does not take into account the performance during the test or the number of tests failed before passing the test. This allows pilots to receive certification which would be "washed out" in the military pilot selection process and leaves pilots in the system, which are not really capable of being pilots. The investigation was an "eye opener" in that respect.
The crew squandered time and attention in conversation that should have been used to attend operational tasks. The male captain did most of the talking giving the impression, that the flight was just a means to him to talk to the female first officer.
The Dash 8-400's primary flight display does not provide a yellow "low speed" caution above the red "low speed" warning on its airspeed indicator and thus is not consistent with current recommendations and requirements. Crew perceive, that as long as the indicated airspeed is within the "black band", the speed is normal. Therefore if such a caution band had been available on the display, it would have likely raised a "red flag" with the crew.
Colgan's flight crew manuals did not provide any information about the symbology used on the air speed indicator, especially it did not explain the red band and that the stick shaker would activate upon reaching the top of the red band. A board member got the impression from talks with Colgan pilots, that they were not aware, that the red band was fundamentally equal to a barberpole, the airplane should never ever been flown into. The documentation as well as the checklists did not include the Vref switch creating the opportunity for confusion. Colgan actually did not have a full fledged manual to provide for their crew, just an interim manual that showed a lot of deficiencies and is seriously inferior to the de Havilland/Bombardier aircraft operations manual (AOM). The interim manual had been approved by the FAA however.
The Bombardier AOM creates confusion, too, by containing procedures in the landing section, which raise the impression of the airplane being susceptible to tail plane stall. When asked about that paragraph, Bombardier replied that paragraph was left in the AOM in error. The board member voiced the opinion, that the AOM was not thorougly worked through.
In discussing the AOM the board members agreed, that the captain pulling back on the control column would be consistent with the procedures for a tail plane stall and would be consistent with an 8 minutes FAA video about tail plane stall. The captain however did not take enough time to analyse the situation, his reaction therefore is consistent with being startled and confused. The first officer retracting the flaps supports, that the crew was following procedures for a tail plane stall.
Pilots holding ATPLs are not required to obtain or maintain proficiency in full stall recovery. The reason is, that pilots need to demonstrate capability to recover from full stall during their ab initio training. The full flight simulators are not capable of providing fidelity in a full stall scenario. Regulations therefore only require, that recovery from an approach to stall is being demonstrated during simulator training, but do not require to demonstrate a recovery from a fully developed stall.
Sterile cockpit requirements below 10000 feet were violated by the flight crew. Prior to the accident monitoring by FAA had not identified any concern with Colgan in that regards, following the accident the FAA identified several areas of concern. Colgan in the meantime provided their air crew with additional guidance. Pilots (intentionally) diverting from standard operating procedures like the sterile cockpit environment are three times more likely to make additional errors with consequences, studies and previous accidents and incidents have shown. In this flight the conversation clearly took precedence over operational tasks, although the conversation stopped about 2 minutes before the low speed cues appeared. "You do not adhere to standard operating procedures for flights where everything goes smooth, you adhere to standard operating procedures for flight where everything goes sour." The crew had completed all relevant checklists for the phase of flight at the onset of the stick shaker, however were doing some of the checklists late.
Both pilots showed precursors of fatigue. Their sleep prior to the accident had been interrupted and was of poor quality. The accident occured at about the time of the captain's normal bedtime. Witnesses describing the captain's as well as the first officer's usual behaviour and behaviour in the morning of the accident suggest, that both crew may have been fatigued although quantification is impossible. Performance degradation as result of fatigue, short of falling asleep, can however barely be identified. In the accident it is not possible to identify any decision that may have been impaired by fatigue, although the continuous conversation on the flight deck can be seen as result of fatigue. The crew was probably lightly fatigued, but is considered sufficiently fit for the flight. Rest times were up to the choice of the crew members. Colgan however changes procedures and guide lines addressing the issues of fatigue and introduce fatigue management with flight crew. Factors contributing to fatigue of the crew were loss of sleep (sleep deficit), which applies to both crew, and hours of being awake applying to the captain (15 hours awake). The board determined, that the sleep deficit by the captain was between 6 and 12 hours over the period of three days prior to the accident. Counter argument used was however, that the captain was performing a briefing during the approach and was interrupted by ATC, the conversation with ATC taking just shy of a minute. The captain resumed the briefing without "missing a beat". In addition, during the most recent training the instructor observed a tendency to overcontrol the airplane in unusual attitudes by the captain suggesting, that the captain's performance during the accident flight was not degradated but rather matched the captain's core performance.
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