dawie22

Now i know there there are already a few posts on this but i cant really associate with them.

First off, a lil about the plane:
it is a modified West Wing orion, being that the nose has been shortened by about an inch and i have re-enforced and put on a Cox 0.049 (this has been very successfully for me in the past on to of the same kit and allows me to gain enough height for about 45 mins flight on a good day), i have a modified 35mm camera film case as a take (worked in the past and cheap + gives me about 10 mins on straight fuel or 5% [X(])
the all up weight of the plane is 280g
with a mini 4 channel hitec receiver batt pack and 2 cheap micro servo's.

The problem is that on take off the plane will fly for about 50-100m (both powered and unpowered) and then just drop the right wing tip. while the plane is in level flight I'm almost fighting it to keep the nose up even though the C/G is almost spot on but it may be the servo's but dout it, and there is a slight tendency to want to yaw right but not a lot.

now I'm thinking that there is:
1. a slight problem with the wing angle (it being a little LE down)
2. that there may be a little difference in the washout (what looks to be wash out) on the right wing tip causing it to always drop when the model stalls..

any other views on this and other possible causes...
darv

Tall Paul

Your c.g. is too far forward. The up-elevator needed to maintain level flight is too much.. and the plane is stalling.
You might shim up the leading edge to add incidence without moving the c.g. but the plane will fly slower.

dawie22

hmmm, will try tomorrow, goes against me me Experience, but always willing to take advice from Experienced others, thank you and will let you know the results, much appreciated..

darv

BMatthews

What do you mean by "leading edge down"? Compared to what? The only thing that matters is the angle between the wing and the stabillizer. The rest is just window dressing. However if you're fighting to hold the nose up and you say the CG is good according to the instructions then it's quite possible your wing to tail angle relationship is off. An easy way to test this is to use a long straightedge off the base of the wing (assuming the typical flat bottom airfoil) and look at how the straight edge aligns with the stabilizer. The stabilizer (with elevator in neutral trim) should be either parallel to the ruler or have a slightly negative angle. If it's a positive angle to the straight edge then there's your problem. SHim as Paul suggests to get the stabilizer parallel or slightly negative.

dawie22

yep look slike your right BMatthews (so far), there was a slight twist from what i can see and aldo a little positive in the stab. nothing that cant be filed/sanded out. will do a test flight tomorroww (as bro beein on the helis and everything is flat).. thank you darv

Chocks

You don't have enough washout in the wing that is dropping. You have what is called a high speed stall. Do not try and keep flying until you fix it. I crashed a real beautiful Harlequin that had the same problem. It went iknto a high speed stall and crashed into a granite quarry wall. It went into a spin and would not come out. I freaked out but the pros that I was with explained what had happened. Just like a slow speed stall only with speed instead of slowing down. A slow speed stall you slow down to the point you can't control it. A high speed stall is the same except instead of it slowing down and possibly of giving you a chance to catch it a high speed stall picks up speed until either something breaks or it hits something. Make sure you have plenty of washout and the same in both wings. My problem was that I did'nt have any in the left wing and only about a 1/8 of an inch in the right wing. Make sure you have at least a1/4 -3/8 and you will be fine.