boxbeam

My Feedback: (188)

I have an Ikon N'wst Taylorcraft that I built and am having a real tough time with it on takeoffs. This is a 90" span plane with a Magnum FS-91 engine in it with a 14-5 prop. I do a long roll takeoff and at about 4' in the air it wants to do a hard left wing over. It isn't much fun in the air either. It is balanced at the forward manufacturers specs, the wings are straight and the incidence is correct, checked with the Great Planes lazer meter. I have right rudder trim and right aileron trim set for takeoff and it still wants to cut hard to the left when it is barely airborn.
What am I missing here that I should be able to correct this situation?

Ron

alan0899

G'day Ron,
I'm thinking that the plane needs more airspeed, it sounds like it is just above stall speed when you lift off, try a prop with more pitch, or a bigger diameter & more pitch, maybe bigger wheels will help it get up to flying speed quicker for take off, if on grass.

jetmech05

advance the throttle to full power on takeoff..helps elemenate a stall. have you checked laterail balance? how about engine thrust? does it pull more with power than at idel?

boxbeam

My Feedback: (188)

Alan, you may have just hit the nail on the head. The manufacturer warned that when it stalls, it will stall hard like the real plane so keep the flying speed up when coming in for a landing. I am taking it out again tomorrow evening and I will get it up with more throttle, I like a nice slow flying old time highwing, but then again, this is no Piper Cub. I have not been utilizing all the throttle I have and when it does get it into the air, it most likely begins to stall. I never thought of that but now that you mention it, it makes more sense than adverse yaw. Thanks again!

Ron

boxbeam

My Feedback: (188)

No JetMech, I haven't checked a lateral balance, but will just in case that is adding to it. I was just telling Alan that I will use more power on the takeoff also. I was looking for a nice slow climb out, but got an exit stage left. When I cut the power and go into glide mode, the left banking tendency stops. Down thrust is right on the money according to manufacturers specs, that I did double check along with the CG. Thanks for the input.

Ron

da Rock

Throttle like was suggested, but don't do it suddenly.

Bring it up like before until the tail comes up. Then don't slam it, just advance it steadily. You want the airplane to be flying before it gets the power.

And you don't want it to get a sudden shot of power anytime from taxi out until you reach WOT.

Clint H

My Feedback: (1)

I had the same problem on a small ME-109 I built. The tendency to roll left was so bad, it rolled knife edge on me once. I thought of everything mentioned here: balance, high stall speed, warped wing, ect. However, I noticed one other peculiarity, when I pulled into a vertical upline, the model yawed HARD left. When trimming for IMAC this normally means too little right thrust built into the firewall. Once I added more right thrust, the problem disappeared, and now it launches beautifully. I would try adding some washers or a shim behind the left side of the motor mount. Start small and see if it works, then, if it helps, you can work on perfecting it.

-Clint

boxbeam

My Feedback: (188)

Already done that Clint, but I will also add a little bit more like you suggest and see what happens, that did cross my mind earlier. It certainly can't hurt what is happening to me now. Thanks for sharing.

Ron

Fredsterman

Try right rudder, zero ailerons to oppose the torque from the prop, and plane.[8D]

jetmech05

4 useless things in aviation
1. fuel in the fuel jug
2. altitude above you
3. runway behind you
and
4. airspeed you don't have
I always teach to use full power on takeoff's and go arounds...speed and altitude is life...for a more scale like departure..once a positive rate of climb is established you can always keep the rate of climb down and reduce power a little.
sounds like on landings you're need a couple of clicks of throttle, fly the airplane down, as you cross the runway threshold go to idle and begin to flair

boxbeam

My Feedback: (188)

Well guys, I took it out again this evening and it seemed to be that it lacked power on the takeoff as Alan had first suggested, so it has been pilot error all the time. [&o] HOWEVER,,,,, it seems to want to wander quite a bit on its own and requires almost constant control adjustment to keep it level. It needs more downthrust and I think less control surface deflection, it may be a little bit too sensitive because of too much throw. I am going to study through the instruction sheet to see if any recommended throw specs are given, I don't recall seeing any. Any other input would be appreciated.

Ron