I flew this plane for the first time yesterday. At moderate speeds if you give it full up elevator it tip stalls to the right violently. The throws are at min. for test flights. The CG is on the 130mm.The elevator servos are y'd like I use on my other planes. Any suggestions would be appreciated to help correct this.

First I would check the lateral balance, Then I'de check for a lazy or weak servo on one side of the elevator. Then I'de cut down more on the throw. Half of an inch up and down is a good starting point.

I am not having a lot of luck getting mine to 3d very well, it wont harrier and doing an upright elevator without a lot of wing rock has taken quite as bit of work to achive but it can be done. Inverted elevator is solid. I can get a couple of really tight waterfalls that are truly end over end but after two flips it falls to the side, upright flat spins but while it rotates flat it is not very tight and falls kinda fast. inverted flat spin okays but is very touchy and will fall out of the spin if everything is not just right. snaps are very good. But what really keeps me flying the katana is its Knife edge and roll capabilites. This plane flies very easily in knife edge and rolls are super crisp and responsive. Keep the elevator movement on low rate to around 15 degrees of movement for general flying, anymore may cause the plane to snap, if you setup high rates for 3d use plenty of expo. don't be scared of it just know its there and respect it. it doesnt take a lot of elevator for it do tight and fast aerobatics. i set my low rates to the point that a full up elevator input @ 3/4 throttle will not cause the plane to snap out of a loop. Plane lands fine, won't drop a wing until it has almost zero airspeed

good luck
zonk

I think you could benefit from this thread... http://www.rcuniverse.com/forum/m_14..._1/key_/tm.htm
I think I did!!!

live long and prosper

Thanks to everyone who answered. The plane only has 12 degrees of elevator throw on low rates and is laterlly balanced. I had to put 8 oz. of weight on the firewall to balance on the aft end of specs or 130 mm. The battery is in the engine box and throtle servo is on the firewall so cannot move anything more forward. The plane has a saito 150 on it with a 16/8 apc prop. Not doing anything radical it will snap at 50% throttle and full up elevator on low rates from dead level flight. I have been flying 40 years and this is a first . I have had this happen many times with other planes at too much speed and to much elevator. This is my first plane of this style. I know that I am overlooking something simple. The plane cannot do even a simple square loop. Any other suggestions appreciated.

I had a similar problem with mine, I thought one elevator had more thow at max defelection than the other but it was actually too much throw. I believe your problem is not enough speed entering your loop or too much elevator throw. Try less throw and see what happens.

In looking at mine I plan on strengthening the elevator tips as they look a little flimsy. Perhaps your elevators are flexing unevenly.
Just a thought.

_matt