I'm not assuming anything. I am just recommending something. Something that would likely have prevented many crashes, including all of the ones mentioned in the report that involved serviceable aircraft.
It is not a checklist. It is a simple look around at key items after the checklist has been stowed(although one could argue that it is a mental checklist). Takes about ten seconds or so. It becomes a good habit after a while.
Agree. You could label it as good airmanship, a now discrediited term replaced by Non Technical Skills 1-5 or even more?
The following NTSB report is similar to the accident to the Essendon King Air in that the takeoff run was started with the rudder trim full scale to one side. Why the rudder trim was like that was never determined. However reading the NTSB full report on the 737 accident it seems the captain had trouble keeping straight while taxiing for take off so he used the nosewheel steering wheel to help him. That was the first clue that there was someting unusual going on during taxiing. The rudder pedals were offset while the aircraft taxied and during the initial part of the takeoff run flown by the copilot. It was the copilot that alerted the captain that he was having directional control problems during the early part of the takeoff run. The captain took control and aborted the takeoff but due to a combination of pilot error factors the aircraft overran the end of the runway and slid into a river.
In the case of the 737, the rudder pedals can turn the nosewheel a limited amount in either direction but for more turning capability the steering wheel must be used. On the ground a full scale offset rudder trim will cause the rudder pedals to move in the same direction as the trim so in theory it should be obvious from the beginning of taxiing that a directional control problem has occurred. In the case of the 737 an electrical fault most probably caused the rudder trim to move uncommanded. A a matter of interest I experienced this fault during simulator training in UK in 1989. On that occasion I gave the rudder trim a tweak during a one engine inoperative exercise only to find the rudder trim went to full scale without further pilot input.
See more detail below. Keep in mind while the discussion is on the Kingair accident involving rudder trim operation a similar accident to the Kingair occurred in a 737-400 during the takeoff roll.
tcasblue is online now
Report Post
On September 20, 1989, USAir, Inc. flight 5050 was departing New York City's LaGuardia Airport, Flushing, New York, for Charlotte Douglas International Airport, Charlotte, North Carolina. As the first officer began the take off on runway 31, he felt the airplane drift left. The captain noticed the left drift also and used the nosewheel tiller to help steer.
As the takeoff run progressed, the aircrew heard a "bang" and a continual rumbling noise. The captain then took over and rejected the takeoff but did not stop the airplane before running off the end of the runway into Bowery Bay. Instrument flight conditions prevailed at the time and the runway was wet. The National Transportation Safety Board determines that the probable cause of this accident was the captain's failure to exercise his command authority in a timely manner to reject the takeoff or take sufficient control to continue the takeoff, which was initiated with a mis-trimmed rudder.
Also causal was the captain's failure to detect the mis-trimmed rudder before the takeoff was attempted. The safety issues discussed in this report were the design and location of the rudder trim control on the Boeing 737-400, air crew coordination and communication during takeoffs, crew pairing, and crash survivability.
…………………………………………………………………………………………………………..
NTSB Investigation
The Safety Board collected about 90 reports of rudder trim anomalies for the Boeing -737 300/400 aircraft. The majority of these reports were received after the accident and were from pilots who had heard of or read about the accident in various publications. Boeing knew only of six anomalies and the FAA Maintenance Discrepancy Reports showed none. Many reports described the inadvertent setting of rudder trim by the foot of the jump seat occupant behind the captain’s seat. Their shoe sole pushed the trim knob counter clockwise and set left trim. Pages 28 and 29 of the NTSB Accident Report covers this in more detail. The NTSB report is well worth reading in its entirety especially as the Boeing 737-300/400 series aircraft is still used by Australian and New Zealand registered operators.
See: http://libraryonline.erau.edu/online...s/AAR90-03.pdf