yak

[George Petrie]

Hi Guys.
I have finished building a wild hare Yak 80". I flew it at the week end and it wanted to dive, even when it was taxing on the run way. The C of G is as the manual. What I want to know is the incidence angle of the wings and the stabilisers. or any other suggestions I can look at to help. I had to trim the elevators to there limits to help fly level hands off. Look forward to your help.

G.Petrie

PS. This is one very nice model

[yakpilot]

Can you post any pics of your plane? Or maybe some more details about your setup and equipment choices. How much elevator are you having to push when inverted? The standard test for checking CG is to fly level at about 2/3rds or 3/4 throttle and then pull to 45 degree angle(a true 45 is steeper than most people think) and then roll inverted. the plane should continue on the line for a short distance before very gradually falling to the canopy. If it dives right away or takes a significant amount of down elevator to hold the line, it is nose heavy. If it climbs, at all it is tail heavy. Don't take this the wrong way but check that the landing gear isn't on backwards if it has any swwep to it. Yes, I've seen it done more than once I'm afraid.

[gapple12]

	Quote: Originally Posted by yakpilot
	Can you post any pics of your plane? Or maybe some more details about your setup and equipment choices. How much elevator are you having to push when inverted? The standard test for checking CG is to fly level at about 2/3rds or 3/4 throttle and then pull to 45 degree angle(a true 45 is steeper than most people think) and then roll inverted. the plane should continue on the line for a short distance before very gradually falling to the canopy. If it dives right away or takes a significant amount of down elevator to hold the line, it is nose heavy. If it climbs, at all it is tail heavy. Don't take this the wrong way but check that the landing gear isn't on backwards if it has any swwep to it. Yes, I've seen it done more than once I'm afraid.

Yes, what yakpilot said and make sure your engine thrust is correct.