RE: Diving on downwind?
Hi,
Based on what the two Jims have said, (do two Jims make a James?). Do you change anything flying up wind or down wind?
All I can think of is you have something loose that changes if you vary the throttle or the battery has moved changing CoG. Jim/Gollowock is correct up wind or down wind the only thing that changes is ground speed unless you are flying close to a landform or structure that causes turbulence such as a hill top, building, stand of trees.
Sorry nothing more to suggest. You have me intrigued. Please post the problems cause when discovered.
Cheers,
Colin