On Saturday, June 29, 2013 8:22:46 AM UTC-6, Nigel Pocock wrote:
Excessive initial ecceleration can cause problems with certain types. I

have experienced it with 2 types.

PW5 with stick fully forward at the start of the launch. Hard acceleration

caused the glider to rotate from the nose wheel to the tail wheel and

rocket into the air. I only managed to regain control at about 50ft.

The other one is the K8. Light glider, high wing. Similar problem.



If slow acceleration is a safety problem what about the ground run and take

off with aerotow using belly hooks, and autotows?

Here's a PW-5 winch launch done right. Note the 1 second ground roll.
http://www.youtube.com/watch?v=IseFvZXK7Dw

Here's a K8 also with a one second ground roll.
http://www.youtube.com/watch?v=ict8W0Q5ZpA

Both of these launches were at accelerations greater than 1G. Neither showed an "uncommanded" pitch up. So, neither the gliders nor the acceleration are a problem.