"The Real Doctor" wrote in message
...
On 20 Mar, 01:15, Bob Cook wrote:

If we draw vector force diagrams of two identical gliders, one with flaps
extended, and the other with flaps retracted, we can easily see that
"lift" is essentially the same in both cases.

What happens if you extend the flaps on a glider while keeping
everything else (AoA, airspeed) constant?

Ian

I have really been trying to avoid getting involved in this thread. It seem
too much like "I'm smart and you're not". However, I just want to point out
that to maintain the same AoA while lowering the flaps will require the
pilot to lower the nose of the aircraft. This is due to the change to the
wing's effective angle of incidence.

I really question if it is posible to lower to flaps while keeping the AoA
and airspeed constant. I know that maintaining a constant airspeed of 50
kts while lowering the flaps to 90 degrees on my HP-14 results in a 45+
degree nose down attitude. I am positive the wing's AoA changes while doing
so.

Respectfully,

Wayne
HP-14 "6F"
http://www.soaridaho.com/Schreder