Bill,

This is starting to make sense. I take it that there are 2 phases of flight during launch: the "pre-airspeed" and full airspeed phases.

During pre-airspeed the correcting dihedral forces are not strong enough to correct the reactionary torque. Once the model reaches flight speed, however, the dihedral kicks in.

(With rubber power I thought it had to do with the huge burst of energy at release, but I imagine airspeed is also a factor with rubber power)

So, I'll change the thrust angle by about 2 deg (the model is only 14 oz) and launch with a bank-- we'll see what happens.

By-the-way, why do you need to launch with an upward angle when launching into a bank?

Thanks,
George