I recently watched a video of the Boeing 787 training before Farnborough. This aircraft climbed very fast; does someone know the maximum pitch of this aircraft?
1 Answer
30 degrees.
Boeing aircraft, including the 787, have a Pitch Limit Indicator (PLI) in the flight display that tells the pilot how far the wing's angle of attack (AOA) is from stall.
the PLI also is limited to 30 deg of pitch attitude, regardless of AOA.
But it depends on aircraft configuration
During takeoff climb, there is no single target AOA to fly that will guarantee certified takeoff performance. Takeoff-climb AOA will vary with such factors as airplane gross weight, thrust, altitude, flap setting, and CG. Takeoff-climb speeds (hence, AOA) are limited by stall speed, tail clearance, and minimum control speeds. The higher speed and greater thrust of an all-engine takeoff reduce the AOA significantly relative to an engine-out takeoff at the engine-out climb speed (V2 ).
From Boeing Aero No.12
At Farnborough 2014, pilots Neville and Bryan were pulling stunts that would get airline pilots fired. Most airlines limit pitch to 20 degrees (or in a few cases 25) from what I've read.
They kicked off the demonstration with a spectacularly steep takeoff, pitching the plane up just shy of 30 degrees.
I'd guess they flew just inside what Boeing consider unsafe for those conditions.
Boeing won’t reveal ... just how steeply it can take off
From Wired - "terrifying" (my emphasis).
I think we can be reasonably confident that no production 787 will ever, after take-off, initially climb at greater than 30 degrees.
Flight envelopes
The way I understand it, asking about the "maximum" of anything for an aircraft is less useful than understanding the flight envelope. This is because the maximum depends very greatly on the exact situation of the aircraft including things like altitude, weight, speed etc.
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$\begingroup$ Ok, the aircraft speed depend of Altitude, Engines and all of this stuff. But the conditions of the demonstation, I think, was : Takeoff in Farnborough (238 ft) at maximum power of Engines, and an aircraft without interior. See the demonstration here $\endgroup$– KromenCommented Jul 31, 2014 at 12:18
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$\begingroup$ @Kromen: From that angle it looked more dramatic than it actually was. See updated answer ... $\endgroup$ Commented Jul 31, 2014 at 13:05
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$\begingroup$ Thank you, obliviously is not considered as safe takeoff but it's very spectacular. $\endgroup$– KromenCommented Jul 31, 2014 at 14:27