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Old October 7th 03, 09:56 PM
Ewald Bombelka
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"Scott Correa" wrote in message ...
OK people, what was the verdict.
I'm sure some logger equipped pullups were made.
Who wins?? Wet or dry.
I still think wet pullups go higher, but I can't prove it.

Scott.


Let's continue a bit with physics and math:

I solved the equation of motion for an ascending flight path of a
constant angle with the following parameters:

mass of the glider = 325 and 525kg (= 750 and 1160 lbs)
drag coefficient = 0.015 (constant with velocity)
wing area = 10.5 m^2
start velocity = 185 km/h (100kt)
final velocity = 110 km/h (60kt)

density of air = 1 kg/m^3
gravit.acceleration= 10 m/s^2

I did not account for the initial rotation from normal glide path into
the ascending flight path and I did not account for the subsequent
rotation back into normal glide.

Results for an ascending constant glide path angle of 10°
for the 325kg glider compared to the 525kg glider:

The heavier glider can go up with an angle of 10.8° in order
deaccelerate in the same time (9s).

Both gliders reach the final velocity after 380m flight path.

The 325kg glider climbs to 65m,
however the heavier 525kg glider reaches 70m.

The reason for this is, that the second deaccelarating term in the
equation of motion is: drag/mass, when resolved to acceleration; hence
deaccelaration due to drag is less for the heavier glider.
Robert has already given a vivid explanation for it.

This result (altitude difference=5m=16ft) is less than the observed
altitude difference for the two Venti
(where is the discussion thread ?).

Ewald