Originally Posted by Dutch M
Let's extend this: Headwind 49.99 kts and the Storch is having a collide with a tower, best would be just above a platform.
What would happen: A very gentle little bump against the tower and then the subtle drop/land on the towers' platform. Nothing bent.
Not quite. The plane would still be "flying" while touching the platform as long as the platform is not applying any force to the plane. If you change the control surface settings you can generate a net downward (and backwards) force on the platform that must be taken into account. Or you can lift off again and ride along 0.2 mm off the surface of the platform. When in that stable condition the forces on the aircraft are balanced, and easiest viewed and determined by considering the ground as your reference.
(Then ask yourself if having said sail plane stationary 0.2mm above the ground neither ascending nor descending is at all realistic.)