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Old 16th February 2005 | 15:05
  #22 (permalink)  
Sootikin
 
Joined: Jul 2004
Posts: 17
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From: Home for bewildered engineers
FakePilot :
>Consider: A 737 with 2 engines produces max 50K thrust. But it
>can lift and hold some 130K pounds. So in this case, you get >80K pounds for "free."

This time, a reply without sarcasm.

Forces are vector : they have both magnitude AND direction. Generally, Thrust and Weight act at right angles to one another, and thus do not interact.

I refer you to the Lift/Thrust/Drag/Weight diagram at:
How Planes Fly
For steady, level flight you just need Thrust = Drag, and Weight = Lift. There's no direct relationship between Thrust and Weight.

(Yes, it's a bit simplistic, but it is basically correct.)

Try considering your 737 flying vertically upwards : you'll soon see that you're not getting 80K for free.
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