Airplane Structure

Q: The NTSB recommends that airlines and pilots be made aware that structural protection of an aircraft is not guaranteed when certain, extreme control inputs are made. Why is it possible to make control inputs that jeopardize the integrity of the aircraft? Why isn’t a plane designed so it is impossible to make such inputs? To use a crude analogy, my car does not let me drop into reverse at 60 mph.

True, and neither do state-of-the-art aircraft allow you to bank past certain parameters, pitch past certain parameters, and so on. Airbus was the pioneer, in fact, at using electronics to help keep human beings from crashing airplanes. But it’s very hard, and probably a bad idea, to program out every last edge-of-the-envelope temptation. There can be cases when severe, otherwise dangerous, inputs are needed.

Just as with driving, certain actions are foolish only under certain combinations of circumstance. Just as you wouldn’t feel safe in a car that can never be dropped into reverse, you wouldn’t feel safe in an airplane that can never be banked, pitched, or yawed past certain values. This gets complicated, but in a way that’s the point: trying to fine tune exactly how and when certain inputs might be harmful begins to introduce more and more variables — speed, angle of attack, altitude, etc., etc., — to the point where such safeguards become immensely complex and, possibly, prone to failure.

And there are plenty of ways in which you can still wreck your car, even as the most obvious ones are automatically disengaged.

This article is part of a collection that originally appeared on Patrick Smith, 38, is an erstwhile airline pilot, retired punk rocker and air travel columnist. His book, Ask the Pilot (Riverhead) was voted “Best Travel Book of 2004” by Patrick has traveled to more than 55 countries and always asks for a window seat. He lives near Boston.