Hi all

first post

i recently built a seagull Harmon RocketIII. This is my 4th plane in my fleet and have had it flying (6 flights so far) pretty good in slightly windy conditions. It seems to have a tendency to fishtail (wag its tail) when above half throttle.

I cant seem to work out whats causing it. all my linkages are working correct and there is no slop. ailerons and elevator are hinge taped.

I am running a OS 50sx with a 11X6 master airscrew scimatar prop. Other than the fishys in flight (it tracks straight on the runway) there are no other problems with this beautiful model.

any help on this problem would be greatly appreciated. thanks

Daniel