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Old 2nd September 2006 | 15:58
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Luc Lion
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Joined: Mar 2006
: PPL
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From: Vance, Belgium
The position of the CofG (provided it'swithin limits) does not influence much the AOA of the wings. The wing AOA will be what is required to produce the lift at the given speed.

However, the AOA of the elevator is directly influenced by the position of the CofG since the elevator has to exactly negate the moment arm produced by the pair weight@CofG / lift@CofP.

For the cruise, the optimum elevator AOA is the one for which the drag is minimal. For a symetrical elevator, this is AOA 0° producing no lift and thus matching a CofG exactly at the CofP.

For the best climb rate, the optimum elevator AOA is the one which produce as much lift as possible for a limited drag. This lift adds to the wing lift and thus increases the climb rate. This elevator AOA produces an upwards moment arm that matches a slightly aft CofG.

Last edited by Luc Lion; 2nd September 2006 at 16:16.
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