I have a biplane Pheaton II from Balsa Usa. I have a Magnun 65 engine which is a little bit bigger than recomended (Recomended .40 to .60). The engine fits a bit too hight from the cowling (almost imposible to put cowling).

My question is: What would happen if I bring the engine mount about 3/4 or 1/2 an inch down?

Would it have any effect on the performance of the plane?
Would it fly? What would it do?

Thank you,

Paul

The engine center line and fuse center line must be the same otherwise your plane will tend to climb or dive all the time depending on the position of the engine. Sorry I forgot this is biplane and I don't know much about them :stupid:

My dad has one of these that has bee through about 50 wars. I don't think ANYTHING is where it's supposed to be anymore, and it still flies fine. I don't thing dropping the engine 1/2" or so will hurt. Unless of course, your planning to fly it in competition

The moving the thrust line down a bit will have very little adverse effect if any. Do watch the incidence setting on the wings though. On mine, I found that the top wing needed to be about 1.5 degrees less angle of attack than the lower wing. I did have to add some right thrust also but, once trimmed out, this was one of two bipes I have that require no trim changes when you go inverted; i.e. hands off level flight either upright or inverted.

some times as the engine speed changes the plane will go up or down a little when the engine has been move from the thrust line,some times nothing changes,I have seen some planes improve in performance,not a very firm answer but that has been my personal experience.

Thank you for all your responses

Paul