need help,, possible ignition interferance problem???
Ok Fellas, I need your help,,
I have a giant ESM 96" B-25. I have probably about 15 flights on it now and have a problem that has me stumped. I fly with a spektrumDX-18 G2, it is a proven radio, I have been flying with it for 2 years, never any issues, and all of my other planes and turbine jets fly just as they should . My B-25 has two DLE-35 gas engines , the ignitions are controlled with a smart-fly regulated dual igntion fiber optic cut-off Ignition Cutoff, Regulated for Dual Ignition Engines , powered by a 2600 fromeco LI-ION. The receiver is a spektrum 20ch powersafe telemetry receiver. The Rudders on the B-25 are in each stab, so one servo per rudder,, they are however together with a Y-harness on a single channel. The servos are hitec HS225, they were brand new for the plane, as well as the Y-harness and extensions.
Now,,,,, Here is the problem, and it does not happen all the time, just random but when it happens its consistent and dangerous. The rudders will deflect, and go a substantial amount either direction on their own, This will only happen when the engines are running, and usually get worse as you advance the throttle as observed on the ground after landing. When the engines are not running it is rock solid, I shake and bounce the plane to see if it is a loose connection and the rudders never move, it only happens when the engines are running. I have had it happen to me a couple times in flight, forcing a fairly tense landing, the plane will yaw side to side unpredictably sometimes worse than others, once landed you can see the rudders pulse side to side, give it throttle and see it get worse, and I am not talking about the normal shake from vibration, this is alot of movement I am talking about. kill the engines, and the rudders are rock solid again. Wait for a little bit, start the plane back up, do a preflight check and the rudders dont do it, but while in flight it will happen again.
I have checked my caps and they are secure on the plugs,, my best guess is there is some kind of interference with the ignitions causing the rudder movement? but why only the rudders? and How can I be getting this interference using a fiber optic ignition kill? How can I fix this, guy at the field mentioned some kind of magnetic ring. Of course another member believes its a bad connection at the Y harness, although I always use servo safety clips. Another club member believes the rudder has "a dirty Pot" I looked at him and told him there are two rudder servos, he said probably both of them are that way, but I dont buy that idea at all. I am always learning and hoping someone can put their input or experience in on this to help me out as this is the first time I have had this kind of problem, Thanks Fellas
Ronnie Dean
Last edited by raron455; 07-28-2018 at 12:23 PM.