ER4. How many times during the last (TIME PERIOD) did an in-flight aircraft on which you were a crewmember experience uncommanded movements of any of the following devices…? [Question GER2 parts A through F on the GA questionnaire asks for the same information].

Without a post-flight analysis of the data, the pilot is unlikely to know which devices experienced uncommanded movements. Specifically, the pilot would not necessarily know if one surface moved initially and thus caused another or other surfaces to move, the secondary movement being what was observed and reported.

ER7. During the last (TIME PERIOD) how many times did an inflight aircraft on which you were a crewmember experience a total engine failure? [Question GER5 on the GA questionnaire asks the same question.]

A situation that might be interpreted as a total engine failure by the pilot may not, in the final analysis, be considered or reported as an engine failure in FAA or industry databases. For example, an accessory or component failure that reduced thrust or revolutions per minute could cause the perception of an engine failure, but upon analysis, it would be determined that the engine itself did not fail and the event would not be reported as an engine failure in FAA or industry databases because the event did not meet the established definition of an engine failure.

TU2. During the last (TIME PERIOD), how many times did an aircraft on which you were a crewmember encounter wake turbulence that resulted in 10 or more degrees of aircraft roll? [Question GTU2 on the GA questionnaire asks a similar question.]

The actual extent of the roll cannot be reasonably determined by a pilot without post-flight analysis of the flight data recorder. At some airlines, such post-flight analysis has often indicated that the “startle factor” of uncommanded pitch, roll, or yaw change has resulted in pilots overestimating the degree of change encountered. General aviation planes are not typically equipped with flight data recorders, which rules out even the possibility of a post-flight analysis of data in this segment.

WE5. During the last (TIME PERIOD), how many times did an aircraft on which you were a crewmember encounter wind shear or a microburst condition that resulted in an airspeed deviation of 15 knots or greater? [Question GWE4 on the GA questionnaire asks for the same information.]

The extent of the airspeed deviation cannot be verified without post-flight analysis of the flight data recorder. In such atmospheric conditions, it is very difficult for the pilot to assess the airspeed deviation accurately because of the limited time and ability to view the airspeed indicator during a recovery procedure.

There is an additional question—GER7, below—on the GA questionnaire that the committee believes asks pilots for information that they were unlikely to be in a position to have.

GER7. During the last 60 days when you were a pilot or copilot, how many times did you discover that (an airplane/a helicopter) had incorrect or bogus parts installed?

A pilot would not likely know that an incorrect or bogus part had been installed unless the people performing maintenance or repair on the aircraft communicated that information to the pilot.

The following questions from the AC and GA questionnaires were identified by the committee as questions in which there were problems with the structure and/or wording of the question:

AH10. During the last (TIME PERIOD), how many times did an aircraft on which you were a crewmember take off with an out-of-limit center of gravity?

It is unclear if question AH10 asks whether the pilot knew about the center of gravity (CG) condition prior to starting the takeoff roll or whether the pilot did not know about the CG condition until becoming airborne and experiencing flight control surface difficulties. In the first case, the error is with the pilot’s judgment for taking off in an aircraft known to have an out-of-limit CG, and in the second case the error is with the ground crew for failure to load the aircraft within its CG limits. From the standpoint of trying to reduce such potentially unsafe events, distinguishing between these two markedly different causes would be critical.

AH11. During the last (TIME PERIOD), how many times did an aircraft on which you were a crewmember take-off overweight?



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