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I have heard of pilots rolling airplanes that aren't approved for it (Cessna 172, Learjets, etc.), and other than the obvious legal issues, are there any mechanical or safety reasons to avoid it?

DISCLAIMER
I do not advocate doing anything (like this) that is not legal, but am looking more for additional reasons that I can use to dissuade people from doing this when they say that it isn't hurting anyone or something along those lines.

voretaq7
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Lnafziger
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  • Wouldn't it be approved, if it were safe to do so? – Keegan Nov 03 '14 at 03:49
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    @kjmccarx Not necessarily, the aircraft manufacturer may not have wanted to spend the money to certify that with the FAA due to the cost. – Lnafziger Nov 03 '14 at 05:55
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    @SpongeBob: Also remember that while barrel roll does not involve any unusual loads and should be doable with almost any aircraft, an average pilot not trained for it may easily loose spatial orientation. A business jet crashed couple of years ago because the pilots (it was ferry flight, so only the pilots were on board) wanted to try a barrel roll and lost spatial orientation. – Jan Hudec Jun 04 '15 at 14:00

3 Answers3

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There are a lot of good reasons not to roll such an airplane.

  1. If the plane has gyroscopic instruments, you might tumble them (cause the spinning gyro to hit the inside of the instrument). This can be expensive.

  2. You might easily over-stress the air frame. Normal category light aircraft are rated to -1.5 to +3.8Gs. (That's for a new aircraft) A botched roll can easily hit 4.5 or higher.

If you over stress the air frame, you might just put a lot of very expensive "wrinkles" in the skin that would be very hard to explain to the FBO, your boss, or the insurance company. Trashing the gyros would be cheaper.

If you're not lucky, the wings fold up and you fall out of the sky. It's a stupid way to die.

  1. Non-aerobatic aircraft typically have limited elevator authority; once upside down, you might find it very difficult to keep the nose pushed up high enough to keep the roll going. Turning a botched roll into a "split-S" is one of the worst "recovery" mistakes you can make, and you're setting yourself up for it.

  2. Non-aerobatic aircraft often have gravity-feed fuel systems. A little bit of 0 or negative "G" and it will get very very quiet in the plane. Some people consider this silence detrimental to the continued safety of the flight.

  3. Non-aerobatic aircraft rarely have inverted oil systems. As the engine gets quiet, it also loses most of its lubrication. Bare metal on metal friction can be detrimental to achieving TBO.

Having said all that, in the hands of an expert, it is technically possible to barrel roll most aircraft.

A good way to tell if you're an expert is to call your insurance company and tell them exactly what you plan to do. If they'll quote you affordable coverage, you might be an expert.

Obligatory links because if I don't include them someone else will:

If you want to roll an airplane, contact your local aerobatic club. In the US and some countries, it's the [International Aerobatic Club][5]. Get some competent dual instruction in a suitably rated airplane.
MaximEck
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Dan Pichelman
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    I think it was a 707 that Tex Johnson rolled. It was done during a presentation of the plane, in front of the president of Boeing and an FAA representative. There were reporters on board, and one of them managed to get a photo out of the window when the plane was inverted. – Edward Falk Dec 30 '13 at 22:36
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    And as shown in the Bob Hoover video, a properly-executed barrel roll is a gentle positive-g maneuver all the way through. In theory, you could do this with any plane, as Tex Johnson demonstrated. In practice, don't do this unless you're Bob Hoover. – Edward Falk Dec 30 '13 at 22:40
  • @EdwardFalk - you are correct, it was a 707. I've updated the answer. Thanks – Dan Pichelman Dec 31 '13 at 20:06
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    +1 for "Some people consider this silence detrimental to the continued safety of the flight". That made my day. – Colin Cochrane Aug 18 '14 at 15:05
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    Tex Johnson got chewed out by the head of Boeing for that one. – GdD Nov 09 '15 at 15:05
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    LOL super answer, dude :) – Fattie Nov 12 '17 at 13:14
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    on thing, the "iced tea" video is actually behind a BBC regionwall in most regions, perhaps someone has a better link for that. – Fattie Nov 12 '17 at 13:16
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    @ColinCochrane Mine too!! – Cpt Reynolds Dec 19 '18 at 17:38
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    I’d give another +1 if I could for one of the the best universal life hacks ever seen on aviation SE so far: “A good way to tell if you're an expert is to call your insurance company and tell them exactly what you plan to do. If they'll quote you affordable coverage, you might be an expert.” – Cpt Reynolds Dec 19 '18 at 17:43
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    Tex Johnson's roll was the result of an expert test pilot, keeping the aircraft at 1G during the entire roll, so the aircraft wasn't stressed and the lube systems weren't affected. Most weekend pilots don't have the experience to pull that off and keep the G forces constant throughout the roll. An impressive display of precision piloting. – tj1000 Dec 20 '18 at 02:53
  • Points #3-#5 seem to be referencing the type of roll ("aileron roll"?) where the G-loading goes negative when the aircraft is inverted. The definition of "barrel roll" may not be entirely universally agreed on, but it's not that. (Definition of "aileron roll" may not be entirely universally agreed on either--I've seen some rolls that stayed positively loaded described as "aileron rolls", they just involve less total heading change than a "barrel roll".) A "slow roll", on the other hand, unambiguously goes negative. Maybe there's a new ASE question in the making here. – quiet flyer Jan 30 '23 at 17:03
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A barrel roll, when properly executed, does not put the aircraft through any unusual stress and is possible with almost any aircraft.

However it is only true if it is properly executed. Make a small mistake and you can easily put more stress on the aircraft than it can handle, put it to a spin, starve the engines of fuel (if you let it slip into negative G) or simply loose spatial orientation (especially in older aircraft with mechanical gyroscope that would tumble) and then you'll end up like these two pilots in Cessna 550B Citation in Germany in 2010.

Jan Hudec
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  • A barrel roll is not a ‘cross-controlled’ manoeuvre. Done properly, the slip/skid ball stays centred, a glass of water on top of the panel will stay in place with the water level exactly even. You could leave your seat belt unfastened and Mr Hoover could pour you a cup of tea. – Forbes Jan 28 '23 at 12:23
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Do not even think about it unless you are an expert. I read about an incident in Sport Aviation in which a non-aerobatic performer rolled a piston twin. The airframe was overstressed and it broke up in flight. All four on board were killed.

ptgflyer
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