A Tale of Two Takeoffs

On Mon, 19 Jun 2017 03:58:42 +0000, George Haeh wrote:

My limited exposure to aerodynamics textbooks leaves me with the
impression that airflow behind the vehicle is neglected.

When heavy jets came out, there was a spate of light aircraft crashes in
wake encounters, followed by NASA research and guidance on avoiding.

I have not come across any formulae for air behavior behind aircraft.
There

FWIW the angles and wake thicknesses I quoted work well for free flight
model design, where we know from experience that a model with its
tailplane in the wing wake is not stable in pitch. I've used these values
when designing an F1A with its wing on a low pylon to check that the
tailplane would outside the wing wake. Drawing the diagram said the
tailplane should be in clean air above the wing wake. The model's in-
flight behaviour shows that was a good prediction.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |