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So, sort of inspired by this question, I was wondering if there were any passenger airliners with enough thrust to fly straight up, supported purely through the thrust of their engines rather than the aerodynamic lift generated by their wings - so that once it's flying along, it can just point its nose at the sky and go straight up; if you think about the launch of the Space Shuttle, you’ve got the right general idea. According to some of my comments, this is apparently called a "zoom climb". Note that I'm not asking about VTOL, since some aircraft that are capable of this may not be capable of VTOL due to a lack of thrust vectoring.

I know that some military fighter aircraft are capable of this, but based on some research with Wikipedia, it appears that the Boeing 747, Boeing 787, and the Airbus A380 can't - though the 787 would almost be able to do it if it had four engines rather than two.

Are there any passenger aircraft that are capable of doing this? Obviously they wouldn't do so while passengers were on board, but I'm just interested in the ratio between Operating Empty Weight and Maximum Thrust.

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  • $\begingroup$ Jets are kind of hopeless. The maximum thrust is like half of minimum weight. Props are close at low speed. Maybe Tupolev Tu-114 has some potential as its the most powerful prop plane. $\endgroup$ – user3528438 Feb 8 at 8:15
  • $\begingroup$ @user3528438 According to the formula for propeller planes on the Wikipedia page for thrust-to-weight ratios, the values vary dramatically based on how fast it's going; at its maximum airspeed, it's nowhere close (about a ratio of about .19), but it goes up the slower the plane goes. $\endgroup$ – nick012000 Feb 8 at 10:35
  • $\begingroup$ @ymb1 I just realized I removed your edit, just to explain: I think the question is basically about thrust to weight. Zoom climb is about converting horizontal speed to vertical speed, which (of course ) heavily involves aerodynamics. Question seems to exclude aerodynamics. I bet most airliners are capable of brief zoom climbs... $\endgroup$ – Jpe61 Feb 8 at 11:16
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    $\begingroup$ @Jpe61: Edits to improve clarity are a collaborative effort, so thanks. But now I don't see how it's different from VTOL or hovering, which would make it a duplicate to at least 3 questions on the site, of which the one nick012000 linked. If they can't hover, then they can't climb vertically with just the thrust. This is my confusion. $\endgroup$ – ymb1 Feb 8 at 11:30
  • $\begingroup$ @ymb1 My question isn’t about VTOL because a plane that might not be capable of VTOL but still qualify for my question if it’s not capable of vectored thrust. If its thrust is horizontal, then it would need to take off horizontally before pulling back and pointing its nose at the sky to climb vertically. $\endgroup$ – nick012000 Feb 9 at 0:23
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No, there are few planes that can do this at all. In order to be able to climb out straight up you need a thrust-to-weight ratio greater than 1. In other words you need enough thrust to propel the full weight of the aircraft up without the wings generating lift.

Wiki provides a brief list of aircraft and associated thrust to weight ratios, the Concorde comes in on top at 0.372 with full afterburner but this is at max weight. Although at its empty weight it was pushing a 0.877 ratio. Even running on fumes would not have done it at full afterburner in the Concorde. For comparison the 757-33 has a ratio of 0.6 at Operational Empty Weight assuming a maximum thrust of 42,600 lbf per engine.

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  • $\begingroup$ Wayne Handley had the Oracle Turbo Raven which at the time at least was the only such aircraft with such a thrust-to-wait ratio: youtube.com/watch?v=DvxqbX3s_oE $\endgroup$ – Kirk Woll Feb 8 at 14:15
  • $\begingroup$ The Turbo-Raven was a single seat-aerobatic craft with not a single passenger, it was not an airliner. $\endgroup$ – Guy Inchbald Feb 9 at 14:26
  • $\begingroup$ @GuyInchbald of course, which is why it was a comment. I just thought it was an example that might be of interest to others. $\endgroup$ – Kirk Woll Feb 9 at 14:54
  • $\begingroup$ Then may I suggest you modify the assertion that it was the only "such" aircraft (which in the present context implies it was an airliner) to, say, the only civil aircraft? $\endgroup$ – Guy Inchbald Feb 9 at 15:14
  • $\begingroup$ @GuyInchbald I see your point. I can't edit my comment at this point, but if I could I would have rephrased to "was the only aircraft with such a thrust-to-weight ratio". $\endgroup$ – Kirk Woll Feb 10 at 0:31

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