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I was reading this question and trying to think of ways to park an aircraft tail-to-terminal without using reverse thrust, and this question popped into my head:

Are there any aircraft that could, under their own power, do donuts on the ground without risking significant damage to the aircraft?

Intuitively, it seems like there'd be two main problems:

  • Donuts are hard on the tyres even for automobiles, and for aircraft, which usually use much-higher-pressure tyres carrying much-higher loads than automobiles, dragging the tyres sideways across the tarmac could be expected to produce a much-higher risk of serious tyre damage than with an automobile.
  • Keeping the aircraft from accelerating forwards during the maneuver would probably be difficult.
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    $\begingroup$ It is called ground loop (en.wikipedia.org/wiki/Ground_loop_(aviation) ) isn't it? :-) Maybe not exactly, but it shows you main weak point, fuselage, landing gear attachment etc is generally rather weak against such forces. $\endgroup$
    – Martin
    Feb 25, 2023 at 15:32
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    $\begingroup$ Certainly many small planes can turn with one main not moving (pivot around the wheel). No great smoke show though. $\endgroup$
    – tedder42
    Feb 25, 2023 at 15:34
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    $\begingroup$ A tailwheel airplane on ice can do donuts nicely for multiple revolutions without dragging a wingtip. Wheels sliding very sideways but admittedly not smoking! At least, that's been my firsthand experience with radio-controlled models. $\endgroup$ Feb 25, 2023 at 16:32
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    $\begingroup$ @AdityaSharma, merely “going around in circles” isn’t the same thing as doing a donut… A donut entails breaking traction on the back tires(s) to make a circle much tighter that otherwise possible, like this: youtube.com/watch?v=PY6Xh5YyfYQ That bush plane is actually doing the opposite, making circles much larger that it is normally capable of turning. $\endgroup$ Feb 27, 2023 at 17:21
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    $\begingroup$ @MichaelHall Well then that's probably the closest we can get to a plane doing donuts 😅 because as you said, in order to brake traction at the rear wheels, you need to transmit power through them (or in FWD cars, you must use the handbrake to lock the rear wheels), and planes normally cannot do that. I do agree with what you say about the turn radius... $\endgroup$ Feb 27, 2023 at 20:44

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No.

Burnouts, fishtailing, powerslides, drifting and donuts are done by breaking the traction of the back tires on high horsepower rear wheel drive cars. Once the wheels are spinning there is then very little resistance to side forces. Aircraft do not power their wheels, therefore there is no similar means to break the back end loose.

The only way to enter a slide would be to make a hard turn at high speed. However, if you tried to do this on anything but the most slippery icy surface the aircraft would likely just tip over and scrape the outside wing.

Other that very low CG race cars, most cars will roll if thrown into a sideways skid on dry pavement. Aircraft typically have an even higher CG than cars, plus a narrower track and taller struts, so there's no good reason to expect you could perform a controlled slide.

But, really there's no need to even consider such an option since airplanes can turn much tighter than cars by locking the inside wheel and pivoting around it.

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  • $\begingroup$ I don't know much about "drifting" but I thought it's what the "cool kids" were into and they seem to like front-wheel-drive imports --?? -- just a thought-- I really don't know anything about it, occifer Friendly (joke) -- may or may not be related to a way to edit answer to improve-- $\endgroup$ Feb 26, 2023 at 19:44
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    $\begingroup$ @quietflyer, No, pretty sure drifting is the exclusive domain of RWD cars. One of the "cool kids" works at my place, and he explained how he modified his AWD Subaru to RWD only for drifting by disconnecting the front transfer case. $\endgroup$ Feb 26, 2023 at 19:47
  • $\begingroup$ Cool-- got it-- $\endgroup$ Feb 26, 2023 at 19:50
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To make a donut, the power must be transmitted to the ground by the wheels. Airplanes instead transmit their power to the air using a propeller or a fan.

However airplanes do also burn rubber during landings, for instance when the wheels have to almost instantly match the spinning rate the runway is asking for.

Or when landing under strong crosswind, in which case the wheels touch the runway at an angle relative to their rolling direction, and do skid a bit along this lateral component.

The B-52 bomber is equipped with a swiveling landing gear that, among other induced benefits, mitigates this issue during crosswind landings, by orienting the wheels along the runway, even if the bomber approaches at some significant yaw deviation relative to runway axis.

If such a swiveling landing gear could allow full 360° rotation, then an airliner equipped with this system could taxi towards a terminal, and convert its final small forward momentum into some elegant half donut maneuver about its center of gravity, allowing a tail to terminal stop.

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    $\begingroup$ In all fairness, the donut is made by sharply turning (resisting forward motion and creating a yaw). This sets up a condition (not unlike a spin) where the outside tire (with the engine revved and clutch engaged) travels further than the inside one, making it less prone to lose traction. The inside one "burns rubber", the outside one drives the vehicle around. A "donut" with an aircraft can be done with differential braking, creating the same effect, especially combined with hard prop blast on the deflected rudder. Abuse of an airplane though. $\endgroup$ Feb 25, 2023 at 20:39
  • $\begingroup$ @RobertDiGiovanni, I disagree. In all but the most slippery conditions the outside wheel is likely to “grab”, causing the airplane to tip and scrape the wingtip. $\endgroup$ Feb 26, 2023 at 16:34
  • $\begingroup$ @MichaelHall there are actually a few ways to "donut". The one Quietflyer mentioned works because the rudder does the spinning and none of the wheels has traction. But, yes, if the outside wheel can grab, the inside wheel would have to be locked. If done too fast, like you said, the airplane tips. $\endgroup$ Feb 26, 2023 at 16:46
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    $\begingroup$ @RobertDiGiovanni, yes, on ice. As I said, "in all but the most slippery conditions" the answer is no. $\endgroup$ Feb 26, 2023 at 16:58

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