Spirit Elite drops wingtip...

[dwoel]

I need some help here. I have been flying a spirit 2 meter that I built from a kit. It flew great. I was then given a Spirit Elite kit (not the ARF). I built that and it is my first full house ship. My problem is that it wants to drop the wingtip in a turn. The inboard wingtip just drops into a spiral dive unless you make a really big turn. I don't know if it's the plane or my flying technique. I currently have it set up without aileron flap mixing, so the bank is only controled by the outboard aileron surface. Could that be my problem? I'd like to here some thoughts on this. Has anyone else had a similar problem? Thanks for any thoughts.

[e-sailpilot86]

sounds like you're getting a mild tipstall... It occurs with my DLG if I'm flying too slow, or if I have a tailwind, and if I'm pitching up too much upon entering the turn, a habit that a pilot pointed out to me a few months ago, I didn't know I was doing it either! :p It shows how delicate a balance you need just to turn efficiently. So, fly a little faster, ensure you aren't popping up upon entering the turn, and maybe add a little camber across the entire wing during turning. Oh! It could be because you don't have any aileron differential as well. So, I'd assess these things first, and aftwards, I hope your plane flies well. :)

[Harvard]

Also check for wing warp. Place or tape some stright dowel or square stock across the under side of the wing and sight them to see if the wing is twisted. It could be that one of the wing tips has negitive washout, twisted down. It could cause that side to stall before the other and cause it to drop into a spiral. I have a Sprit 78" and it does the same thing if you dont keep the speed up and check and fix warps with a heat gun.

Good luck

Harvard

[11b2c]

Try an experiment- enter your next turn at a higher airspeed than normal with the same amount of bank you would have used at a lower airspeed. If she tracks well through the turn, you should have a pretty good idea that the problem was energy management- previously you were turning at too slow an airspeed, or you may need washout. If she still goes into a spiral, you know it's not a tipstall; rather it may be a coordination issue.

You may have to find a different turning style than you're used to. For example, my Gentle Lady needs constant rudder in the direction of the turn to maintain bank angle, whereas my old Spirit and Gemini needed opposite rudder in the turn to keep the turn from tightening. In some older full-size glider designs like the Schweitzer 2-33 it is perfectly normal in a tight turn to apply rudder in the direction of the turn and nearly full aileron against it. This is due to the long wings of a glider- the inward wing is naturally going slower than the outside wing. In effect, in this type of turn you are effectively increasing the camber on the inside, slower moving wing to compensate for its slower speed. One of these techniques, when applied correctly to your glider, will produce nice, tight, coordinated turns.

SO experiment with different inputs of elevator, aileron and rudder and, combined with good energy management (I.E. keep the speed up), you should be able to correct the problem.

[dwoel]

Thanks for the tips guys. I'll check everything out the next available flying session. I see your point about the different techniques. i am used to flying a poly ship, and the Elite's dihedral wing will probably take some getting used to. I do have differential set up in the ailerons, but only the amount called for in the instructuions. I'll watch my speed and experiment. Thanks again

[Al M]

With my Spectra, I had to reduce control throws. I cut decalage to 2 degrees and the tip leading edges are sheeted. I also used a V tail. It also reguired some washout. At first I used a lot of washout but as I got things under control I found I could greatly reduce the washout. I am not sure if it would be ok without any but I am not about to try at this point. It started out as an ugly flyer and became a pleasure to fly. On occasion it will still tip stall but it is not violent and it can be caught without a large altitude loss.