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Old 7th April 2002 | 20:39
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overstress

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Sorry mate & at the risk of starting to sound boring, the question I asked was (at the start of this thread) when is lift greatest.

Not CL!

Cl varies with aoa, not lift

Lift = weight in S&L flight

Forget max aoa etc, it's a red herring

Please don't question the lift equation I quoted because a chap called Bernoulli (who was cleverer than I will ever be) invented it.

In your example you forget that as soon as the ac starts to climb, there is a vertical component of thrust which is helping it go up

May I suggest the excellent description at the Nasa website which shows the diagrams I am referring to

here

You will see that as you incline the aircraft in its climb, the lift vector rotates away from the vertical and it actually becomes LESS than the weight.

The ultimate example of what I mean is the rocket - it goes up but there ain't a whole lot of lift generated initially!

The answer isn't as simple as you think!

PS -please no more replies I've had enough

Last edited by overstress; 7th April 2002 at 20:53.
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