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A small highly loaded surface (in this case the elevator) will just stall if forced to too high an incidence. Hence the way to generate more aero load for a given incidence, is more airspeed. The ground effect is most likely also increasing which will be going in the wrong direction I.e requiring more nose lift moment. So now for take off velocity at rotation Vr, goes up and the kinetic energy increases by the square, which is bad news for stopping within the remaining runway (aka balanced field length). The brakes convert the kinetic energy into potential energy and the amount of energy they can accumulate before melting is governed by the thermal mass in the disc’s. That’s impossible to change if you’re original calculations are wrong but you can get a bit more stopping performance from a reverse propeller pitch (beta pitch, ok for flight test but a no no for certification) ….. as long as you don’t run out of runway.

<blockquote data-quote="Zoo Tycoon" data-source="post: 624818" data-attributes="member: 1642"><p>A small highly loaded surface (in this case the elevator) will just stall if forced to too high an incidence. Hence the way to generate more aero load for a given incidence, is more airspeed. The ground effect is most likely also increasing which will be going in the wrong direction I.e requiring more nose lift moment. So now for take off velocity at rotation Vr, goes up and the kinetic energy increases by the square, which is bad news for stopping within the remaining runway (aka balanced field length). The brakes convert the kinetic energy into potential energy and the amount of energy they can accumulate before melting is governed by the thermal mass in the disc’s. That’s impossible to change if you’re original calculations are wrong but you can get a bit more stopping performance from a reverse propeller pitch (beta pitch, ok for flight test but a no no for certification) ….. as long as you don’t run out of runway.</p></blockquote><p></p>

[QUOTE="Zoo Tycoon, post: 624818, member: 1642"] A small highly loaded surface (in this case the elevator) will just stall if forced to too high an incidence. Hence the way to generate more aero load for a given incidence, is more airspeed. The ground effect is most likely also increasing which will be going in the wrong direction I.e requiring more nose lift moment. So now for take off velocity at rotation Vr, goes up and the kinetic energy increases by the square, which is bad news for stopping within the remaining runway (aka balanced field length). The brakes convert the kinetic energy into potential energy and the amount of energy they can accumulate before melting is governed by the thermal mass in the disc’s. That’s impossible to change if you’re original calculations are wrong but you can get a bit more stopping performance from a reverse propeller pitch (beta pitch, ok for flight test but a no no for certification) ….. as long as you don’t run out of runway. [/QUOTE]

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