UM T-28 motor problem
Beautiful morning for flying, just a whisper of a breeze, so tried the T-28 again, found it had too much positive pitch, which is why it looped like crazy yesterday, managed to smack the tape fence where I was flying and cracked the tail. Two pieces of tape and a tweak on the elevator pushrod, and back in the air it went, NOW it was flying nicely. Made a few passes around to get the feel of the plane, managed to lose it in the sun for a few moments, managed to gain it back without crashing, and proceeded to make a nice aproach and landing. YEAH, Got it back up and fly it around a bit more then lost it a few times, no damage, then while Ihad it up and doing a couple loops and rolls the motor started to sputter, so Ibrought it down, then managed to overshoot and smack the fence again. Cracked a wing this time, but other than that the plane is holding up well.
SO to find out why it was sputtering I held the plane and gave it throttle, it spun up and stopped. OK maybe thats what it does when the battery is low. So grabbed a fresh one, put it in, and no throttle. None whatsoever. Tried a different battery, same thing, no throttle, everything else is working. Ibrought it in, thought mabye I knocked the connector loose, and pulled the canopy off. Nope connector is snug and tight. Did the motor quit? Went and grabbed my mSR which is apart at the moment waiting for new blade grips and plugged the motor into where the main drive motor goes, put in a battery and connected the radio, motor fired right up smooth as silk and ran fine. So I put it back together, and noticed it has a 3 connector plug, and plugged it into the left and center pins, plugged in the battery and the motor took off backwards. Pulled it out, put it into the correct pins and put the battery on. Nothing, no throttle still.
Ithen decided, not really know why, to turn off the TX, and then back on. Motor started up and I had full throttle. OK This is crazy, so I pulled the battery, and taped the canopy back on, plugged the battery back in, no throttle. Ifiddled with the TX a few more times, and eventually got throttle again. Iran a full battery through, took about 5 minutes to deplete it, and the motor started to stutter and then quit. Not much warning, I would thing it would wind down first before it quit, but it just quits. Popped in a fresh battery, and again, no throttle. A dozen flips on the TX , still no throttle. Tried to rebind it, no throttle, picked a new slot on the TX, bound it, no throttle, Reset it to the original position, no throttle.
What the heck could it be? It didnt hit that hard, and everything moves smoothly, and the throttle, when it did work, was 0-100% just fine, no vibrations, nothing loose. Could it just be a flakey main board? The nose gear had clipped the fence on the last hit, and slotted the cowl, and that is about the only visible signs, other than a couple pieces of packing tape where the wing and tail cracked, but no dents or other damage, since Iflew at only half throttle and wasnt going very fast at all.
I really like how this plane flys, and am really not happy that I barely got one battery out of it before it quit working. I highly doubt the crashes caused this.