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Old 29th October 2012 | 10:49
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Tiennetti
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Joined: Nov 2004
: ATPL
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From: CarrotLand
Your last question, made me think about a glider.

When you pull a glider with another airplane, there is no "thrust" as such, nor vertical component of the same (it is pulled forward and normally it lifts off befor the pulling airplane)
In that case, YES the lift overcomes the weight of the same

On the same principle, on your A320, you use the thrust to accelerate along the runway... imagine an infinite runway and no speed limitation, your aicraft will be lifting off in a flat attitude just because at that speed, the lift is bigger than the weight.
What you do at "rotation" is changing your Cp (and thus your lift, considering the same speed), not rotating the thrust vector upwards

The thrust vector is there, indeed, but its effect is playing a negligible effect on the vertical axis

Last edited by Tiennetti; 29th October 2012 at 10:51.
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