[Unified-mailman] Fluids question F1

[Mark Drela]

>So do I have to calculate the acceleration of the plane 
>from t=0 to t=4. a=(v2-v1)/delta t or
>are you saying that the acceleration 
>is so small during the brief rotation period that I can say acceleration=0 
>and that v is just a constant=vtakeoff

The latter.

But the reason why you can assume v=constant over the rotation
is not because acceleration is small.  It's because the rotation
time interval  delta t = 4s  is short enough to produce only 
a neglible velocity change v2-v1 during the rotation.  So
v2 ~ v1 ~ vtakeoff