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Old 29th Aug 2011, 09:36
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Diablo Rouge
 
Join Date: Nov 2009
Location: Great Britain
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Serious question for a QFI

Ladies / Gents,

Ones son has asked a question concerning the four forces on an aircraft when under 'G' and I would be grateful if someone were to offer a simplistic answer.

He understands the four forces and that to maintain flight lift has got to be equal or greater then weight or gravity. He has stated that when pulling '+G' the aircraft and occupants weigh many times their static weight. Logic therefore states that increased lift is required when pulling +G.

In trying to answer, I mentioned that G is always married to momentum at which time he shot me down by posing a question about approaching the top of a loop and losing momentum whilst maintaining +G. Clearly the aerofoil section and surface area are a constant on all but swing wing aircraft, therefore how is the need for increased lift met on a conventional aircraft whilst sustaining G.

To keep things resonably simple; in a scenario of a run-and-break for example. Genuine question requiring sincere replies please.
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