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Ailerons & Crosswinds

To The Letter

Directional Control on Runway

Dear Editor:

After reading Transportation Safety Board of Canada Final Report A97Q0015, referenced in your "CRM Classic - Takeoff Gone Awry" article published in ASL 4/98, I was struck by the brief mention of, but not the emphasis on, what I believe may have really triggered the accident.

It is true from the crew resource management (CRM) aspect that a bad chain of events was set up by the crew. The trigger, however, was the directional control on the runway. I would bet that the pilot flying did not have enough, or, more likely, any aileron deflection into wind. I came to this conclusion before going back and checking the runway alignment and wind direction and, sure enough, there it was, a 50 degree crosswind at 20 kt. gusting to 30 kt.

Over the years, while supervising pilots, I have been astonished at the total lack of attention to deflecting ailerons while taking off and landing. It seems to be the very first thing that pilots forget after their private licence, yet it is critical input if proper directional control is to be maintained. On wet, icy, muddy surfaces with a crosswind, aircraft will drift downwind on the roll, both taking off and landing. The application of ailerons counteracts this. In extreme cases, full aileron is insufficient, but this generally coincides with exceeding the maximum crosswind tolerance of the aircraft.

Even on the most icy surface, proper application of ailerons enables good direction control in a crosswind, coupled with proper technique. Most aircraft that are not high-lift types are more forgiving under these circumstances. If you perceive that most newer pilots are flying nosewheel, non-high-lift aircraft and encountering crosswinds and slippery runway surfaces on an infrequent basis, then it is apparent that their level of competency is not too high. Associated with wrong technique, they are a set-up for disaster.

An argument may be made for differential power to correct drift, but this is application of a yawing technique that produces some weathercocking. The power settings are altered, and, assuming full power is set and required, the pilot is decreasing power on the upwind engine at a critical time, and increasing his ground roll. The proper application of ailerons will normally negate the need to adjust the power.

The report mentions only "...It appears that the loss of directional control was caused by the condition of the runway, the environmental conditions, and the late application of corrective measures." It does not mention what kind of control input the PF (pilot flying) was making (or not making). I don't like second-guessing without the facts, but if I am correct, if he is typical of what I have observed, then I am wondering if he has figured it out yet, ready for next time. To all pilots who drift unaccountably on runways in crosswinds, check the position of your ailerons!

Sincerely,
John Warner
Leduc, Alberta

Dear Editor:

In ASL 4/98, "CRM Classic - Takeoff Gone Awry," there is much talk of the first officer (F/O) giving an insufficient take-off briefing, not informing the pilot-in-command (PIC) of his difficulties maintaining directional control, and making the non-standard call "I have reached the speed." With phrases like, "It is possible that the PIC would not have cut power if the F/O had clearly and precisely communicated the loss of directional control of the aircraft and his intention to continue the takeoff," and "...the PIC had very little time to analyze the situation...," the reader is left with the impression that the poor PIC is simply a victim of a bad situation.

Based on your account, the PIC was the major cause of this accident. The first thing I learned in my two-crew training is that, at the command of the PF (pilot flying), in this case the F/O, the PNF (pilot not flying), in this case the PIC, sets and maintains take-off power, monitors the engine instruments and airspeed, and makes any calls covered in the take-off briefing loudly and clearly enough for the PF to hear them. The PNF is not relieved of these duties until after climb power has been set. Had the PIC followed this most basic rule of crew resource management (CRM) there would have been no incident no matter what deficiencies there were on the part of the F/O. This incident happened only because the PIC did not call V1 loudly and clearly enough, and then made the cardinal sin of abandoning his duties altogether by looking out the window. It makes this reader wonder how much of the directional control problems were caused by an asymmetrical power setting by a PNF who was looking out the window instead of doing his job.

Sincerely,
Ian Shipmaker
Salmon Arm, B.C.