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According to comments, it was nowhere near vertical, which is why they didn't show it from a side angle. Apparently indicator light goes off at 30 degrees, indicating imminent engine stall.

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I'm assuming you mean angle of attack, not flight path angle. The aircraft could certainly be capable of a 60 degree climb until it slowed down enough that it couldn't maintain a low enough angle of attack. It probably could only sustain something less than a 30 degree climbing flight path angle (while empty), as that would be pushing the limit of the thrust to weight ratio. That being said cameras can be used in ways that make things look much more dramatic than they actually were.

As a side note, at 30 degrees AoA the aircraft will not be able to continue flying anyway, the wings will have stalled well before that, and the pilot would be made painfully aware of this fact through stick shakers, aural warnings, and very rough tail buffet.

I'm a flight test engineer, so this stuff is what I get to do for work! :)

The video is filmed from a distance using a long telephoto lens, compressing the perspective. The 2011 movie Tinker Tailor Soldier Spy used the trick in a similar scene to a great dramatic effect [1].

[1] https://petapixel.com/2016/01/25/this-dramatic-shot-was-done...

Is that a scene that makes more sense in context? Out of context, I'm having somewhat of a hard time distinguishing it from a bad composition.

One of the characters is trying to get information out of the other by threatening him with being put on the plane, which, it's implied, would take him to an extremely disagreeable destination.

(Unintentionally reduced spoilers due to having forgotten many details of the film.)

Such a good film and book. Oldman plays an impressive smiley

Yes. The staring man (Smiley, played by Gary Oldman) is looking for a spy in his organization. The man being stared at is worried that Smiley is going to kill him (by putting him on the plane). The audience feels the same anxiety by proxy, because it appears that the actors are about to be hit by the propellers.

Look again at the actors. Smiley never stops studying the others' face, while the other looks scared, nervous, shifty, and guilty the entire time. Even without context you should be able to pick up that Smiley is cool as ice, and that the other man has something to hide.

Might have as well been filmed in front of a projection of that plane landing - it looks that way in the beginning anyway.

I think you are referring to the "Pitch Limit Indicator". This is not exactly a light, it's two yellow bars superimposed on the artificial horizon.

The PLI is capped at 30 degrees pitch, but that does not mean that the plane would stall at 30 degrees. You could climb much steeper than that if you had enough speed:

> However, the PLI also is limited to 30 deg of pitch attitude, regardless of AOA. If AOA or AOA margin to stick shaker were to be used as the first and primary focus of the flight crew during windshear escape or terrain avoidance procedures, extremely high pitch attitudes could be reached before stall warning if the maneuver is entered with sufficient speed. Therefore, the PLI shows the lesser of either margin to stick shaker, or 30 deg of pitch. (http://www.boeing.com/commercial/aeromagazine/aero_12/attack...)

Nevertheless, at least according to some Wired article, one of these steep takeoffs was done at a little under 30 degrees. (https://www.wired.com/2014/07/watch-test-pilots-push-the-new...) I guess the pilots use the PLI to judge their pitch attitude.

https://www.youtube.com/watch?v=KYbM-3E11Qo&t=117s

Boeing also released a video of the pilots rehearsing the routine. There's an overhead view of the takeoff - that's a lot steeper than 30 degrees, unless it's a perspective trick.

EDIT: 50-55 degrees seems to the actual pitch angle.

One of the videos I saw of the test planes appeared to be well above 60 degrees. Agreed, not vertical, but far more vertical than a standard airliner. Also, they only maintain the aggressive angle of attack for a very short time, which may lead credence to an engine stall, or an imminent engine stall.

What do you mean engine stall?

As long are you have enough thrust, airspeed and no system preventing you to go above a certain pitch or AOA, then the plane should fly just fine...

I mean the engine stalls, from lack of thrust, and airspeed. A 787 has about a 1:2 thrust to weight ratio. It's not a fighter jet.

Excessive AOA causes streamline detachments in the diffuser that cause compressor stall: http://www.free-online-private-pilot-ground-school.com/image...

Right, but there's no excessive AOA here... except during recovery maybe but I doubt they let it go that high...

Please state clearly and plainly that it is your assertion, as a claimed expert pilot and aerospace engineer, that a stock 787 as shown has enough thrust to achieve vertical flight, as you are strongly implying in your comment. Thank you.

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