HELP! FUTABA 7CHP Issues

[GrayMatter]

Just got back from a rather scary, to say the least, flying session. Two separate planes, both maiden flights.

Flight 1. Yak-54, Futaba PPM Rx, Futaba Digital Servos. Radio check went fine, as expected. Engine start, taxi to runway and rollout went fine. About 100' beyond point of takeoff things just went wierd. At first I thought that I had overlooked something and left something loose. Soon after, it was evident that something significant was happening. Every control surface, but not the throttle, was all over the map. It was all I could do to keep the thing in the air. At times I was full lock with any given control surface. It was far more than a trim issue as direction would vary through pitch, roll and yaw. This has never happened before and as such I was completely overwhelmed. I was able to land somewhat successfully and lost only the landing gear. It was torn from the bottom of the plane, but will be a relatively easy fix. Could have been so much worse.

Flight 2. Seagull Ultimate Biplane, Saito 1.25, Futaba PCM Rx (not the same as the first flight) , HiTec Digital MG & TG servos. I made the mistake here of thinking that the first flight was unique in it's ugliness. Again with the radio check, control surface check, motor run-up and all. Taxi out, rollout to liftoff and let the fun begin. Not quite as eventful as the first flight, but still just not quite right. I've been flying for quite some time now and I've flown all sorts of aircraft in all sorts of conditions. This was obviously not right. Same type of behavior as the first flight. Jerky motions and basically just not a smooth flight feeling. Not necessarily jittery, but just all over the place. I have never had to work so hard to keep something in the air. Fortunately, I was able to land this one successfully and without any damage. Skill? I think not. I'll give full credit to luck on that one.

Flight 3, because I'm an ass. Maybe this last one was just an odd coincidence... yeah right. After a very thorough inspection of the aircraft, wiring, wire routing, antenna routing, throws, etc... I made the idiotic decision to fly again. Surely it must have been an odd moment, two times in a row. So, same ol' stuff. Off the tarmac and then the fun begins, but in a so much more exaggerated and sweat inducing manner. Off the runway, hard left aileron (not of my doing), correct and discover full down elevator, correct and here we go for the roller coaster ride. It's important to mention that left of the runway at this point is NOT open flying area. This would be the spectator, setup, parking and pavilion area. Thirty seconds were spent in what I can only call the ugliest balled up hover over all previously mentioned areas. Luck again prevailed and I somehow pulled the plane back from the brink of balsa heaven. A miraculous landing and cleaning of the shorts soon followed.

It's obviously not coincidence. It's not me and I'm quite certain it wasn't radio interference. The only common factor here is the radio. Futaba 7CHP. What sort of a disaster did I experience? How do I fix it and ideally, how do I prevent it in the future? So, where do I go from here? I'm at a loss. I have four other aircraft programmed into the same radio, some of which have the same receivers. I've done hundreds of flights with no problem and then this. Is it the radio? Is it just plain sh*t luck?

HELP!

[thewrap]

It could be a crystal problem from transmitter to reciever or it's something seriously wrong with your transmitter. Try your reciever with another transmitter.

[Quicksdraw]

Hey Gray,
Notice my post on the 7c. I feel your pain. I have sent mine back for service they said they couldn't find a problem but they replaced the processor as a precausion. Guess what......... nothing has changed. I usually get funky elevator or aileron inputs sometimes throttle and only one lock out. Probably averages two per flight over time.
Maybe we should start logging serial numbers or something?

It does keep me on my toes! I want to say it's made me a better pilot but then again maybe I would be a superstar if my planes didn't have a mind of thier own.
Alex

[JOSE S]

if you have the time check the same radio with another receiver if the problem is still there change the radio for another on the same frequency an another thing do a range check with the engine running it could be the vibration on the engine.

[Matchless]

You mentioned that the only commonality of the flights was the radio, but thats not quite right.... don't forget the environment. Did anyone have an illegal wide band radio? Are there any other known sources of interferance at your field? ETC?

[Quicksdraw]

Mine has hit on all my planes at least six different receivers.

Environmentally, correct me if I'm wrong but won't radio interference effect broadband (all channels) not just elevator or just aileron?