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Old 3rd Feb 2020, 18:39
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pattern_is_full
 
Join Date: Jan 2008
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Given that the FAA handbook is aimed mostly at newbie-fliers getting into the seat of a C-172 for the first time, I'm not sure all its recommendations can be extended to large transport-class aircraft.

What I notice is that most aircraft in which holding the nose off for aerodynamic braking is common (Shuttle Orbiter, military fighters) have a bob-tail construction - less fuselage behind the main gear. Thus they can achieve higher pitch angles on the ground than the general run of airliners, without risking a tailstrike, especially as airliners have been stretched for more capacity. Same may be true to one extent of another for Concorde or other tail-engine aircraft, due to the weight distribution and main gear being further aft, and/or having taller main-gear relative to tail length.

I would imagine that AB drag/effectiveness goes up exponentially (as with many things in flight physics) with the pitch angle that can be achieved.

(One could argue that dragging some aluminum along the ground will add its own braking effect - but it's not very economical: Accident: ACT B744 at Dammam and Jeddah on Feb 1st 2020, tail strike on departure . But as a last resort....maybe better than the alternative)

As a last resort AB has another weakness - the drag will decrease exponentially as airspeed drops. It won't help as much if delayed to the last second.

All that being said, AB is a real effect. It may or may not be a significant effect (deceleration of x-many m/s^2) in any particular combination of situation and aircraft type.

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