Aerobatics Undefined

At the airport the other day, we got into a discussion of FAR 91.307, lovingly known as the “parachute” or “aerobatics” reg depending on who you talk to. The point of confusion was that an instructor had been told by another pilot a while back that doing spins was illegal since they weren’t wearing parachutes. The concerned pilot had seen 91.307 (c) and assumed that since spins exceed 30 degrees of pitch in most cases, that the reg had been busted. However, reading further to 91.307 (d) (2) it clearly states that spins and other checkride-required maneuvers are legal to fly without a parachute. In fact, there is no restriction on attitudes whatsoever provided everyone in the aircraft is a crew member. Actually, 91.307 (c) gives us a lot more latitude than we think. It states the following:

(C) Unless each occupant of the aircraft is wearing an approved parachute, no pilot of a civil aircraft carrying any person (other than a crewmember) may execute any intentional maneuver that exceeds–
(1) A bank of 60 degrees relative to the horizon; or
(2) A nose-up or nose-down attitude of 30 degrees relative to the horizon

If you and a fellow pilot go up and do a 90 degree bank wingover, you do not need parachutes. If you go up solo and pitch up to 50 degrees and do a reduced-G float over the top, that’s legal without a chute as well. If you take your non-rated friend up, you either have to provide parachutes for the both of you, or keep the angles to the 30/60 limit. Also, if you and 3 other pilots go up, the 2 pilots in the back seats do not count as crewmembers so the 30/60 limitation will also apply. Note, that 30/60 is not the boundary of aerobatic flight. The litmus test for what defines aerobatics for your aircraft is in the operating manual. If your manual states that aerobatics are not approved except spins, Chandelles, accelerated stalls and Lazy-8s, then you know that rolls are out of the question. But nowhere in the FARs does it describe aerobatic as being flight in excess of 30/60 degrees. FAR 91.305 defines aerobatic flight as:

For the purposes of this section, aerobatic flight means an intentional maneuver involving an abrupt change in an aircraft’s attitude, an abnormal attitude, or abnormal acceleration, not necessary for normal flight.

That’s pretty vague, probably one of the most open ended regs next to 91.119. What defines abnormal? What is abrupt? And what is normal flight? I get the feeling when this was written, it was with point to point transportation in mind. As such, the regulation is conspicuously open-ended to allow for other types of operations that involve more aggressive maneuvering. The catch is that the FAA can also randomly define what “normal” and “necessary” is in response to a complaint or to issue a violation. But there is still another catch. “Aerobatic” also counts as a category of aircraft.

Say that I’m out over farm fields at 3,000 feet AGL in a utility category airplane doing wingovers. My airspeed never even gets into the yellow arc and my G-load never goes over 2.0. An overeager observer down below assumed that I was “hot-dogging” and “barnstorming” and called the FAA to say that I was doing “flips and tailspins in a Piper Cub” (it’s always a Piper Cub to non pilots). Short of having a data recorder onboard, its my word against theirs. Lacking this hard data, its very hard to validate what you did or did not do. And knowing what maneuvers were flown is critical in order to defend yourself. After all, it is entirely possible to do “aerobatics” in normal category airplanes without imposing more than 2Gs on the airframe. Before you get angry and call me dangerous, I’ll explain.

While it would be tempting fate to do a snap roll in a normal category aircraft, you can freely apply full control deflections (well below Va and in one direction only), pitch, roll or yaw to whatever attitude you like. The danger is in building up too much speed in an extreme nose low attitude and needing to pull more G than the airframe is rated to (that’s when you hear the loud POP and then enjoy the rush of the wind as your wingless, tailless airframe plummets to earth). However, an abrupt change in attitude does not always imply a high load factor. Imagine using full aileron in a Piper Saratoga to roll into a steep turn (50 degrees) quickly. Was the maneuver abrupt? Compared to “normal flight” in the same type airplane, yes. Is the attitude abnormal? Not really? Was the acceleration abnormal? Not even close. So was it aerobatic? Ask your FSDO…seriously, find out how they define it.

The more knowledge you have about what you’re doing, the better. An untrained observer may say that they saw an airplane doing “acrobatics” and “stunts” when really you were doing Chandelles. If you can confidently state what maneuvers were performed along with some rudimentary info on entry altitudes and speeds, it may convince whoever is inquiring that you aren’t just throwing the stick around to see what happens. Unfortunately, society loves to point out when they think someone else is doing something wrong or unsafe without actually knowing what was going on in the first place. If you take the chance of actually having fun in other than straight and level flight, there’s the risk that someone with an iPhone is going post video of everything you did while commenting on how “unprofessional” and “dangerous” the pilot of that little airplane was.

Quite frankly, every time you fly, you are at the mercy of someone’s self-narrated cellphone video (even an airplane well above 1,500 feet AGL will show up on a phone camera). The only way to protect yourself legally is to make sure you understand the regulations fully. However, the only way to keep yourself alive is to make sure understand the aerodynamics fully. Use 91.307 to your advantage. Go up with an instructor and practice really unusual attitudes. Take some aerobatic lessons. Get used to the fact that airplanes operate in a three dimensional ocean of air. If your comfort zone ends at 30 degrees of bank, work your way up to 45 and 60 degrees (maybe even a little beyond). Once you experience that an airplane will not just drop out of the sky because the bank angle increased beyond 45 degrees, you will have a lot more confidence in handling it in all phases of flight.

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About Christopher Williams
It's easier to lie about being boring than it is to be honest about being extraordinary.

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