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Old 18th Jan 2013, 02:37
  #36 (permalink)  
Brian Abraham
 
Join Date: Aug 2003
Location: Sale, Australia
Age: 80
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No your right Brian, when the flight controls are failing, a crew calls up dispatch to talk to let the chief pilot know to have catering ready when they land.
You're a jerk (first class), but almost forgivable in a non pilot such as yourself. They did no such thing, as the dialogue of discussion with dispatch I posted above proves.

Lets have a look at the reports discussion re failing controls. I absolutely hate introducing facts into the discussion.
The Safety Board recognizes that, from an operational perspective, the flight crew could not have known the extent of airplane damage. Although flight crews are trained in jammed stabilizer and runaway stabilizer scenarios, the loss of acme nut and screw engagement exceeded any events anticipated in emergency training scenarios, and the flight crew was not trained to devise or execute appropriate configurations and procedures to minimize further damage to the airplane or to prevent the accident. However, the flight crew’s earlier attempts to activate the trim motor and configuration changes may have worsened the situation. As previously discussed, the captain’s activation of the primary trim motor at 1609:16 precipitated the release of the jam and the initiation of the initial dive. However, it was not clear how many times previous to that the flight crew activated the primary trim motor nor was it clear whether or to what extent the prior activations hastened the release of the jam. Therefore, the Board could not determine the extent to which the activation of the primary trim motor played a role in causing or contributing to the accident.
2.2.5.5 Adequacy of Current Guidance

The Safety Board notes that after the flight 261 accident, Boeing issued a flight operations bulletin outlining procedures to be followed in the event of an inoperative or malfunctioning horizontal stabilizer trim system. The bulletin advised flight crews to

complete the flight crew operating manual (FCOM) checklist(s). Do not attempt additional actions beyond that contained in the checklist(s). If completing the checklist procedures does not result in operable trim system, consider landing at the nearest suitable airport.

The Safety Board agrees that this advice is generally appropriate. However, the Board does not agree that the flight crew should merely “consider” landing at the nearest suitable airport if accomplishing the checklist items does not result in an operational trim system. In such a case, the flight crew should always land at the nearest suitable airport as expeditiously and safely as possible. Further, the bulletin provides additional information regarding the possibility that repeated or continuous use of the trim motors may result in thermal cutoff and states that the motor may reset after a cooling period. The Board is concerned that this additional information addressing repeated or continuous use of the trim motors may weaken or confuse the initial guidance to refrain from attempting troubleshooting measures beyond those specified in the checklist procedures.

The Safety Board concludes that, without clearer guidance to flight crews
regarding which actions are appropriate and which are inappropriate in the event of an inoperative or malfunctioning flight control system, pilots may experiment with improvised troubleshooting measures that could inadvertently worsen the condition of a controllable airplane. Accordingly, the Safety Board believes that the FAA should issue a flight standards information bulletin directing air carriers to instruct pilots that in the event of an inoperative or malfunctioning flight control system, if the airplane is controllable they should complete only the applicable checklist procedures and should not attempt any corrective actions beyond those specified. In particular, in the event of an inoperative or malfunctioning horizontal stabilizer trim system, after a final determination has been made in accordance with the applicable checklist that both the primary and alternate trim systems are inoperative, neither the primary nor the alternate trim motor should be activated, either by engaging the autopilot or using any other trim control switch or handle. Pilots should further be instructed that if checklist procedures are not effective, they should land at the nearest suitable airport.The Safety Board also believes that the FAA should direct all Certificate Management Offices (CMO) to instruct inspectors to conduct surveillance of airline dispatch and maintenance control personnel to ensure that their training and operations directives provide appropriate dispatch support to pilots who are experiencing a malfunction threatening safety of flight and instruct them to refrain from suggesting continued flight in the interest of airline flight scheduling.
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