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I would think, for example, all modern fighter jets can maintain 90 degree climbs due to having thrust to weight ratio greater than one.

Are there any other air planes which can do that?

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The general answer to your (general) question is: all airplanes can do that. With every air plane you can accelerate to maximum speed pull the stick until you reach 90°.

The problem is that not all planes will be able to recover safely from that maneuver. Most planes will not maintain enough speed to continue the flight in a controlled manor. That's why the flight management software of modern Airliners will prevent that from happening.

On the other hand there are quite a lot planes out the able to do acrobatics like this. They have specially designed aerodynamic behavior and, if powered, mass/thrust ratio. The powered versions also need special engines that keep running at zero or negative G.


Are you certain that every plane has enough inertia at Vne and enough elevator authority to reach 90° before stalling? – StephenS

My claim holds, when any aircraft can reach a pitch of 90° before its speed is 0 and the pitch rate does not exceed the structural limits of the plane.

When flying strait upward gravity is slowing down the aircraft with 1G (9.81m/s²).

The time to decelerate an aircraft to 0 with 1G is=

t = v/1G

While "rotating" from horizontal flight to 90° angle this deceleration gradually raises. Therefore real time til full stop is longer. But lets keep the calculation simple.

For a Sailplane (no thrust) like an ASK21 top Speed is 250km/h = 70m/s

t =  70m/s / 9,81m/s²
t =  7,135s

The ASK21 must be able to pitch to 90° in roughly 7 second, which is a pitch rate of 12° per second (and it is, I've done it already... ;o))

Lets recalculate for an A380:

Cruising speed 900km/h = 250 m/s

250m/s / 9.81m/s² = 25s
90° / 25s = 3,5°/s

On a quick search I could not find a resource giving the maximum pitch rate of an A380, but I'm pretty sure it is higher.

Conclusion: The faster the plane the more time is available and the less pitch rate is needed to rotate to 90°.

And yes, I keep my statement that (from a physical point of view) every aircraft can reach 90° pitch. But may not safely recover from it.

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    $\begingroup$ See edit. He would want to know an example of a plane with TWR above 2 $\endgroup$
    – Abdullah
    May 15 at 12:28
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    $\begingroup$ Above 1 would surely be enough @Abdullah $\endgroup$
    – Sanchises
    May 15 at 13:31
  • $\begingroup$ @Sanchises typo $\endgroup$
    – Abdullah
    May 15 at 13:46
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    $\begingroup$ Are you certain that every plane has enough inertia at Vne and enough elevator authority to reach 90° before stalling? $\endgroup$
    – StephenS
    May 16 at 3:56
  • $\begingroup$ @StephenS I did dot restrict to stall speed being the a limit, just reaching 90° pitch still moving upward potentially below stall speed. But after the calculation in my update I'd say yes to that too (still saying that it will not maintain enough speed to recover safely). $\endgroup$ May 16 at 11:11

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