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Old 22nd October 2008 | 20:28
  #66 (permalink)  
ChristiaanJ
 
Joined: Jan 2005
Posts: 2,315
Likes: 10
From: France
Originally Posted by ft
ChristiaanJ,
welcome to the dark side!
LOL.... But I don't mind admitting I got it wrong.... Nothing beats pen and paper and thinking about it, rather than "off-the-cuff".
However, L = W*cos(ca) does hold true.
Right. My mistaek was not looking up cos(ca) for something like 6° climb angle, which is pretty well negligeable compared to sin(ca), hence negligeable in the vertical force balance relative to T*sin(ca), even with T ten times less than W.
You forgot to factor in D*sin(ca) in the world-vertical force balance. Have a look at balsa model's diagram in post #26.
Oops. Yes, I goofed there. But even in my quick-and-dirty example, T-D is still 200 kgf, so the vertical component is still 20 kgf, so the lift will still have to decrease by about 16 kgf.

Thanks all! I'm enjoying this.

CJ
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