At 13:43 14 March 2009, The Real Doctor wrote:

Bad example, since tow planes pull - give or take a wee bit -
horizontally, regardless of climb angle.


Well, our tow plane certainly does not pull horizontally!

I figure it pulls at about a 10:1 angle or about 5.5 degrees.

So if you didn't like my last example here is some more for you:

If we took a 900# glider and pulled it up at 5.5 degrees climb angle, the
lift would be 895#......

Just for ****s and giggles, if we had a (lot) more more powerful towplane
we could get the following:

Climb angle 10 degrees......lift 886#
Climb angle 20 degrees......lift 845#
Climb angle 30 degrees......lift 779#
Climb angle 40 degrees......lift 689#
Climb angle 50 degrees......lift 578#
Climb angle 60 degrees......lift 450#
Climb angle 70 degrees......lift 307#
Climb angle 80 degrees......lift 156#
Climb angle 90 degrees......lift 0#

As climb angle increases, lift decreases!

Same for dive angle!

Granted, at "normal" climb and descent angles the reduction in lift is
tiny, but it is a reduction non the less. Just trying to dispell the
rumor that lift somehow must increase in a climb.

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