vandiggity22

Hey all, running into a little problem with my GWS beaver. When I first flew it the other day, it wanted to bank/roll left all the time, so I had to correct with lots of right rudder to keep it flying. This was with about 3 degrees of right thrust and about 2 degrees of down thrust. Made for a real interesting landing, pretty much no rollout. So I took it home and shimmed the motor for about 5-6 degrees of right and 3-4 of down. This did help some, but it still crabs in flight, almost like when you're fighting a crosswind when landing(it does this to the same side going both directions down the field, so I know it's not crosswind.) And speed doesn't seem to be a factor..........Also, it I checked the vertical stab, it's straight. Checked the wings, they're level and don't have any noticable twist. I'm using the 350 gearbox motor and 10x4.7 prop with 1250mah 2cell lipo. Any insight appreciated!

Pilot352

First, they do make ointments for them beaver crab critters!!!

Okay, joke done!!! *laugh* *laugh* *laugh*

I feel better now!

I'm assuming that the plane flew correctly before right? The only things I can recommend checking would be:

1. Wing and vert stab straight. (you did that)
2. Wing isn't twisted. (you did that)
3. Motor not mounted on any angle. (normally these types of planes put some down force in the motor mount, but not side to side).
4. Did you make sure the wing struts aren't causing drag?
5. Did you make sure the wheel struts and wheels aren't causing drag?

If you check most everything, drag on one side over the other or balance may be off. Check the roll balance from nose to tail. Make sure you don't have one side heavier than the other.

Good luck

-Pilot

vandiggity22

Yeah, I had a major brain fart for not catching that title right off.....oh well. I don't believe that the struts are causing drag as they are the same on either side. Also the landing gear is the same from side to side. I've played with the fairings on both a little, but it doesn't seem to make any difference. Also, I should have noted that it has flown like this from the start. thanks!

soarhead-RCU

Van:
Sure has the symptons of a warped wing and in the GWS potato chip wings it is pretty common. Try holding the plane out in front of you nose to nose at arms length and level. Then site across the wing with the TE just showing below the LE. Should be equal. Or take the wing off and put each panel on a known flat serface and see if they lay flat. If warped they can be twist straight with a good hair dryer.
Just my thoughts
Bob

vandiggity22

Ok, I think I've got a bead on it now. When holding it at arms length and viewing it from the front, everything looks good, nice and straight/even, neither trailing edge droops or anything, but still was having the banking/crabbing problem this morning. Well, after my third Crab/spot/bounce landing I was taxiing back to my truck and caught a rock and nosed it over. With the sun coming through the foam wings, I could see a difference between the two wing panels. When I was assembling the wing, everything seemed even, thickness was the same, no twist etc. But now I can see that the left wing panel seems less dense inside the foam. When I flexed and twisted the wing panels( I never did this before because I didn't want to bend/break them)the left was FAR LESS rigid than the right. So I think what's happening is when it's in the air, and the wings are under load, the left one flexes up towards the trailing edge tip and causes a up aileron effect. (Note: this model does not have ailerons, I just couldn't think of a better way to describe it.) So I"m going to have to come up with some way keep the wings from flexing around. Maybe a different wing altogether.................

mrluke

or add alerons

soarhead-RCU

If you have any foam(depron-bluecore maybe even thin balsa) you could make some ribs and it might give it enough support so it wont flex. Also did you do the strapping tape on the TE and the X mod? That may just help you out also
Good Luck
Bob