Wikipedia:Reference desk/Archives/Science/2017 December 19

= December 19 =

Jumbo jet
Dear Wikipedia. Can a Jumbo jet fly upside down? If so, has this ever been done? Please answer accurately as there is £50 riding on this. And if at all possible by 11.00 pm (which is when the pub closes). Thank you. 86.187.163.251 (talk) 20:53, 19 December 2017 (UTC)


 * Only if Tex Johnston is flying the plane. Count Iblis (talk) 21:00, 19 December 2017 (UTC)


 * Can a Jumbo Jet fly upside down? No. Dolphin  ( t ) 21:19, 19 December 2017 (UTC)
 * Both Federal Express Flight 705 and United Airlines Flight 93 flew upside down for short periods as violent struggles for control occurred in their cockpits; they were smaller aircraft, not wide-body aircraft, but I see no reason that the larger aircraft couldn't do the same . Nyttend backup (talk) 21:26, 19 December 2017 (UTC)
 * I take it back — FEF 705 used a DC-10, which is a jumbo jet. So yes, one hijacker proved that it is possible to fly a jumbo jet upside down, and seeing that he and the crew all survived and landed under control (despite his best efforts), it is proven that it is possible for a jumbo jet to do this without breaking up under stress.  Nyttend backup (talk) 21:29, 19 December 2017 (UTC)


 * Don't think a Jumbo (or other passenger aircraft) has flop-tubes in the tanks to continuing feeding fuel to the engines when flying inverted. Aerodynamically though, sure, even a ham-fisted pilot should be able to keep the kite in control -until it hits the ground. So yes, a Jumbo will fly  inverted but without power. Aspro (talk) 21:28, 19 December 2017 (UTC) 21:27, 19 December 2017 (UTC)
 * I was thinking more of a large loop or barrel roll which will keep positive g. Greglocock (talk) 21:29, 19 December 2017 (UTC)
 * To do a barrel roll, press Z or R twice! --47.157.122.192 (talk) 05:48, 20 December 2017 (UTC)
 * Well maybe a bit...
 * "Goodrich, a 32-year pilot - first with the Air Force, then with Delta Air Lines -- trained pilots to fly MD-88s, which the movie's (Flight (2012 film)) plane most resembles. During production, Goodrich said he reminded Zemeckis and Washington that "you can turn an airplane like this over, but it's not going to fly like this very long. It's gonna go down." "He looked at me and he said, 'Can it fly upside down for a little bit?' I said, 'Yeah a little bit, but eventually you're gonna lose lift in the wings and you won't have the power to keep the airplane up.'". Can airliners really fly upside down? by Thom Patterson, CNN (January 2013) Alansplodge (talk) 21:34, 19 December 2017 (UTC)


 * Virtually any plane can fly "upside down" if it can maintain positive G forces and a non-stalling Angle of attack. "Upside down" can still satisfy those requirements.  Jumbo jets can do barrel rolls.  What they are not good at is recovering from an aerodynamic stall/spin.  Acrobatic and military fighter aircraft recover quite well.  In addition, the positive G requirement is needed for proper fuel and oil flow.


 * Recap:' So which way is this £50 bet going to go ? Think it is agreed that even a Jumbo is controllable whilst inverted. Yet, like any other aircraft that is not designed to be fully aerobatic it wont fly like that for very long. There is only 55 minutes left before the UK pub closes at 11' O'clock, so time is of the essence P.S. Contrary to popular belief, even a pig will fly if provided with enough momentum, from being placed in say a Trebuchet. But I must admit, that they have a little bit of trouble taking off unassisted. Aspro (talk) 22:07, 19 December 2017 (UTC)
 * Some "pigs" can actually take off unassisted, though. 2601:646:8E01:7E0B:0:0:0:64DA (talk) 09:52, 20 December 2017 (UTC)
 * Along those lines, I recall there's a saying among aerospace engineers that "even a brick will fly given sufficient thrust". The Space Shuttle was sometimes called a "flying brick" in its glider mode (re-entry to landing), because it arguably "fell with style" more than it "flew". Shuttle pilots trained to "fly" it in an aircraft with the landing gear down and the engines in reverse, to match the Shuttle's "flight" characteristics. Here's a video on this. Anyway, there isn't really a "right" answer here. Human language is full of ambiguity; you could argue endlessly over the definition of "fly". For "real" disputes along these lines, we rely on a justice system to resolve them. This is why legalese is so stilted: to try to minimize ambiguity. --47.157.122.192 (talk) 05:48, 20 December 2017 (UTC)