Tip stalling Extra
 

Hi, hope someone can help!

I have a Mid west Extra with a Zenoh 45 in it. The span is 78". The model is mint to look at, and it flys as if on rails. It will do any trick in the book i am capable of doing! I have been flying for twenty years now with many diffrent models, but cannot get my head round this one so hense the posting.

The Extra will fly fast and smooth. It will hover in a light ish wind, but when it gets close to the ground on landing, bang it tip stalls (always to the left loking from the front) no warning at all. I have played with the c of g, and balanced it side to side. Nothing helps. I bring it in fast but it will still try to stall and anyway the result of a fast landing and the tip stall are the same. The undercarrage comes off. I am sick of it being a one flight wonder when you go out for a days flying. I have got to the stage now that the airfame as nice as it is will be retired. I thought that i would post this in one last attempt to crack the problem.

If the landing could be fixed it would make a perfect model.

Regards

Paul

RE: Tip stalling Extra
 

Serpant: Have checked to make sure that your "incedence" is correct? I have corrected some of the aircrafts tendacy to drop a wing and stall, by simply putting a couple turns down trim in my ailerons. Seems to give a little more lift at lower landing speeds. Good Luck.

RE: Tip stalling Extra
 

Hi, i have tried a little up and down, and mixed flaps in with the elevator. That did not cure it. I was thinking of adding a little packing under the front of the wing and the airframe to change the incedence, but not really sure why. In my mind if i angled the wing down lightly it may have better lift with the nose up. Maybe someone might say weather that is a good or bad idea.

RE: Tip stalling Extra
 

Sundance: If you're not sure that your incedence is correct, add a 1/8th shim under the leading edge of the wing. Do not shim the back of the wing up. Sounds like you may have a little negative incedence. Keep us informed on how it fly's after you raise the leading edge a little.

RE: Tip stalling Extra
 

I had a Midwest Cap 232 with Zenoah G45 and experienced the same stalling characteristics on landing. What I observed was that the plane was fairly heavy, probably approaching 17-18 lbs, and it was a matter of wing loading. The Midwest planes build heavy compared to the latest ARF's. I eventually changed the engine to a BME 44, which is considerably lighter than the Zenoah, and this helped somewhat.

You didn't mention the weight of the model.

I know that there is no quick fix to reducing weight, but this may at least explain the problem.

RE: Tip stalling Extra
 

I was thinking the same thing. a heavy plane won't slow down with high wing loading. and it does have a zenoah up front which is heavy to start out with.

RE: Tip stalling Extra
 

Hi, will give the shim a try weekend weather permiting. The plane is at a guess 15lbs. I will weight it. A guy at our field has the same plane with a moki 210 in it and the model is perfect no tip stalling at all. I do know that we have a mid west cap in our club with a Zenoah 45. That will tip stall but no where near on the scale of my Extra. I can expect it if i was flying to slow, or on a dead stick landing with no wash over the plane from the prop, but at a good brisk pace i think the plane should be better.

Thanks for your imput this far.

Paul

RE: Tip stalling Extra
 

I agree totally about the symptoms of flying a heavy plane. His complaint is that it tip stalls. He says it flys fine when its flying fast. Just because it lands fast shouldn't cause it to "tip stall." My suggestion to raise the leading edge by 1/8th inch will allow the wings too have a little more positive attack angle as the aircraft slows down. Of course you will have to re-trim the plane at high speed. It's my opinion that nothing affects the way an airplane flys more than ....... # 1, wing incidence. and #2 the balance point. I repeat......This is my opinion only.

RE: Tip stalling Extra
 

Hi Bob

I agree if the plane was to heavy it would need landing faster. As the other guy's have said. I think, and hope you are onto something with the wing incidence. If it hovers in a brisk wind with only prop wash, but then tip stalls at speed near the ground i dont think that is weight related. I think with it only tipping one way is another clue. I think that when i flair out on landing if the incidence is wrong will create this stall.

I hope this is the case as the plane is mint and it would be a shame to break it.

RE: Tip stalling Extra
 

Hi, this is a link to a photo of the plane

http://www.3drc.info/directory/gazextra.JPG

RE: Tip stalling Extra
 

Very pretty airplane Serpant. Sincerely hope you get the problem worked out.

RE: Tip stalling Extra
 

Here's the Problem...the plane is Heavy on the wing...plane and simple, High Wing Loading = poor slow flight

I have some experiance with the same plane, ours came in at 18 lb and with onle 1200" on the wing it flew crapy...Yes as long as you flew fast it was ok, but when we tried to slow it down it was tippy and eventualy we retired it to the inferno...

Sorry to be so harsh on this plane...

RE: Tip stalling Extra
 

Not necessarily. Many aircraft fly in overweight conditions without tip stalling. You're correct that planes with higher wing loading will not slow down for landing as well as the same aircraft with a lighter wing loading. I have flew airplanes that were 25% heaver than advertised and the still did not tip stall. If the incidende is correct, the wing is ballanced with no warps in it, it should just drop straight down when it looses all lift. No harm in trying to get the incedence right.

RE: Tip stalling Extra
 

Bob you are correct, infact there are many things you need to have setup correctly before ruling out or giving up on the plane..I only shared my experiance with this particular plane, others Im sure of, have had better results with this plane...

RE: Tip stalling Extra
 

Mu2driver: I concur 100 percent with your statement. Check every possible cause that is suggested (and recommendation) and rule out everything before you totally give up on the plane. If after making any, and all corrections that you find are wrong, then try a lighter engine. If that doesn't make it fly the way you want it too, put it on RC universe for sale. Just fully describe the problems you've had with it and refer them to this thread for reference. I would suggest that you take a picture of it as it is the day you put it up for sale, along with the picture you have of it flying. As a matter of fact...... Just so you can sell it with a clear conscience, why not just auction it off! With a bid starting a $1.00 + shipping. I'll bet you'll be surprised at how much it will bring. Just explore all of your options before you decide what you want to do.

RE: Tip stalling Extra
 

Had a Dave Pratt 330L that had the same simptoms, fairly light bird. Problem turned out to be bad servo on one of the elevator halves. Never got to fly it long enough to really tune it up, it was one of those that shook itself do death.

RE: Tip stalling Extra
 

I'm sorry to hear that your Midwest is tip-stalling. Mine has a Brison 3.2 and flies and lands great. Have you checked the throws on both elevators to make certain they are equal throughout their range of movement? Also, if the ailerons are drooped at all, it will make the airplane tip-stall. Raising the ailerons just a little might help prevent that. Just a couple ideas to hopefully help your bird start flying properly.

RE: Tip stalling Extra
 

Hi thanks for all your imput so far. I do fly it with the ailerons mixed with the elevators. I did think that was a good thing? If i put in more up elevator i get a downward movment is both aileron. Do you think that maybe making the problem worse. I set all my planes up like that.

RE: Tip stalling Extra
 

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RE: Tip stalling Extra
 

Yes, that will DEFINITELY make the problem worse!! The ailerons are outboard on this plane. When they both go down, the wing tips are at a higher angle of attack than the root and it will tip-stall. Take out the mixing (this plane doesn't need it), line up the ailerons with the trailing edge as best as you can and give it another shot. This plane has a lot of potential, once you get this problem worked out you'll be a lot happier with it.

RE: Tip stalling Extra
 

It would have been nice to know this type of info from the begining..

RE: Tip stalling Extra
 

I agree with mostly everything posted. I have flown some peoples overweight airplanes that would not tip stall, while light ones that would snap if you breathed on the elevator or slowed it down. My old H9 540 would 3D decently, but had the same problem. Had to come in at a very high speed or you would drop a wing hard. It was OK at high speeds, fine in high alpha, but it hated being in between. I think it had a warp that got worse over time in the trailing edges of the wing tips, and it weighs 16.5 lbs wet, so that wasn't helping the problem at all either.

Brandon