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Could airplanes, in theory, be designed to takeoff by first tying the tail to a post, throttling the motors to full power, and then letting loose?

Could it even take off while tied, if the cable is attached to a point that's higher than the tail of the aircraft?

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    $\begingroup$ A common short-field technique is to apply the brakes, then go full throttle. After the engine has reached full speed, release the brakes, and the plane begins moving very quickly for a short takeoff. $\endgroup$ – abelenky Jun 18 '18 at 12:55
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    $\begingroup$ Prior to WWII, 2-5 ground handlers would hold the airplane's horizontal stab or wings until full throttle was achieved. This technique not only provided the shortest takeoff, but it also allowed a quick engine test on planes without brakes. $\endgroup$ – jwzumwalt Jun 18 '18 at 15:58
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    $\begingroup$ For some time to climb record attempts, the plane was chained down, engines were brought up to full power and then explosive bolts were blown to release it. So the technique is doable, but not of normal use. $\endgroup$ – zeta-band Jun 18 '18 at 18:24
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As already mentioned, aircraft cannot take off without moving through the air, because it is the airflow around the wing that generates the lift required for take-off, and the only practical way of generating sufficient airflow around the wing is to move the wing through the air. This is typically done by moving the wing, and thus also the fuselage it is attached to, forward.

There is, of course, another way to look at that: aircraft can take off without moving relative to the ground, if exposed to a strong enough wind from the front of the aircraft.

That said, keeping the aircraft stationary, "throttling the motors full power, and then letting lose" is a very common short-field take-off technique at least for propeller aircraft; there's nothing theoretical about that. The aircraft is, however, typically kept stationary by applying full brakes while applying full engine power, rather than by using an external tie-down.

The tail likely isn't designed to take the force of holding the aircraft stationary while the engine is running at full whallop, although there's no reason why such an anchor point couldn't in theory be installed (see motor aircraft towing gliders to altitude, scale up somewhat, and you're close).

Since the brakes are already there and need to be powerful enough to at the very least hold the aircraft stationary during the engine run-up prior to take-off, which happens at a significant fraction of full power and can quite well happen at a hold short point just before the runway, there's no reason to spend weight on reinforcing the tail section to that point. Instead, just use the brakes for the few seconds needed.

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  • $\begingroup$ Commercial aircraft used to use this technique regularly. As a child*, I remember sitting on the plane listening to the engines spool while not moving, then the sudden sink into the seat as they released the brakes. *This would have been pre-deregulation in the US: early- to mid-1970s. $\endgroup$ – FreeMan Jun 20 '18 at 18:11
  • $\begingroup$ @FreeMan "Commercial aircraft used to use this technique regularly." Jet or piston? $\endgroup$ – a CVn Jun 20 '18 at 18:14
  • $\begingroup$ Jet. Couldn't be explicit on models, but I'd venture to say 707 & 727. As a kid, I distinctly remember the runup, but don't remember other details. $\endgroup$ – FreeMan Jun 20 '18 at 18:19
  • $\begingroup$ Nope. According to Wikipedia, Ozark Airlines was exclusively DC-9-x by the time I was flying them. (Champaign to LaGuardia via Dulles according to them, but I don't recall ever stopping in Dulles.) According to Wiki, they did order 2 727s but never took delivery. $\endgroup$ – FreeMan Jun 20 '18 at 18:24
  • $\begingroup$ Jets still do a stationary spoolup in short field conditions AFAIK -- fly out of KSNA sometime if you want to feel this sort of thing. $\endgroup$ – UnrecognizedFallingObject Jun 20 '18 at 23:48
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No, an airplane cannot takeoff while tied to a post.

What creates lift is the speed of the wings through the air.
(or the alternate frame of reference view: The speed of air over the wings.)

If the plane is tied to a fixed point, like a post, it is not moving in the air, and the wings will not have any lift.

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  • $\begingroup$ This might be a dumb question, but is it possible for the engines to produce enough wind over the wings for the airplane to take off, despite the plane being on a leash? I'm guessing that that's impossible, but it would be great if you could edit this answer to say so (or to say otherwise). $\endgroup$ – Terran Swett Jun 18 '18 at 14:54
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    $\begingroup$ aviation.stackexchange.com/questions/17406/… $\endgroup$ – abelenky Jun 18 '18 at 15:50
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Well that’s part of a catapult launch from a carrier.

The aircraft is held motionless on the cat by a holdback bar attached to the nosewheel or a holdback bridle which is also attached to an anchor point on the flight deck. The link between the bar or bridle and the aircraft is a frangible metal link, sometimes called the ‘dog bone’ because it is shaped something like a dog biscuit. It is strong enough to hold the aircraft still, even under full power but fractures when the force of the catapult or EMALS is applied to the airframe during the launch stroke.

For terrestrial takeoffs, I suppose one could do something like that but it is much simpler to just hold the brakes, run up to full power, then release the brakes and perform the takeoff roll. This is the preferred method of takeoff for light twins and turboprops, as it minimizes the length of the takeoff roll.

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