Vx/Vy
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Vx/Vy
Just reading up on some POF - looked through some old posts and came across this: "Vy is the speed of maximum excess power = power available - power required. If power available were not a function of speed, that would be the same as minimum power required speed (minimum sink rate for a glider). But since power available increases with speed, Vy occurs at a higher speed than minimum power required."
*"But since power available increases with speed" - can someone explain this to me?
*"But since power available increases with speed" - can someone explain this to me?
Join Date: Apr 2010
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The power available for jet aircraft does increase with increasing speed, assuming constant thrust with increasing speed:
P = F * v
If thrust force (F) is constant and the speed (v) is increasing, power will be increasing as well.
P = F * v
If thrust force (F) is constant and the speed (v) is increasing, power will be increasing as well.
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The power available for a propeller-driven (whether it be piston or turboprop) aircraft also increases with speed up to a point. Essentially 'power available' is 'thrust available multiplied by speed'. Propeller thrust decreases with increasing speed.
