paulace

A question for Andy....or whoever can help. I recently bought a Madhawk 300 (Coast Guard) heli and while futzing with the transmitter, accidentally changed it to a wrong mode and the heli flew into a wall before I could shut it down. No visible damage to the main rotors or rotor head assembly or fuselage, but I did snap all the blades off the tail rotor. Replaced it and everything looks fine, but when I try to fly, the heli spins in a CCW direction and the tail rotor is noisier than I remember. What I'd like to know is - how do I go about diagnosing the problem logically. And what's the most likely cause of this knowing that a smack into a wall caused it. Seems to me it could be A) some part of the linkage in the tail rotor assembly, or B) gyro problem.
Given that the tail rotor seems to be noisier now, I'm leaning toward a mechanical problem in the tail linkage somewhere. I've disassembled as much of the tail as I could without removing the fuselage, and inspected the gears....everything looks OK and the gears all seem to mesh just fine. I've tried holding the tail rotor with my hand and rotating the main rotors manually, and Ican move the main rotors....actually, if feels the same whether I'm holding the tail rotor still or not...if that means anything.

So I'm just not quite sure how to logically pinpoint the source of the problem....anybody have any ideas/techniques? Anything I"m missing?


thanks in advance,



an addendum:

I took the thing apart, and saw that one end of a black wire going from one circuit board to the other in the receiver unit had broken off. Does anybody know where the other end of the wire needs to be attached? I've attached a photo...or at least tried to...


Or is that an antenna?

yadac123

ok if your motor make a loud sound then I'm sure it broken or fried. Please check the tail gears and make sure the gears are still intact and quickly replace the motor. You do not know if the gyro has problem or not unless you for sure know the tail motor is working 100%.

Andy

paulace

Thanks Andy....I've already ordered a new motor.  I'll replace the old one and let you know what happens.

   

yadac123

Andy

paulace

OK, Andy...replaced the motor first. Maybe that wasn't the thing to do, but that's what I did. It didn't fix the problem...the tail was still noisy and the copter spun CCW. So, I replaced the beveled tail gears next even though they looked good to me.. That fixed the noisy part, but the copter was still spinning. So last replacement was the receiver. Put in the new receiver and it seems to work now, though it's very touchy with spin and the tail rotor. I'm going to try to adjust the screw on the receiver that's marked "sensitive"

Any words of advice?

paulace

You know, the copter seemed to work fine before I put the fuselage back on, and when that was done, it began to fly a bit funny....flew OK for about 30 seconds, then started to spin intermittently. So I removed the fuselage and it few allright again. I shortened the tail section of the fuselage by 1/8th of an inch because it seemed to be pulling the tail rotor shaft out a ways to make everything at the tail end fit. I'm still trying to get it to stop spinning with the fuselage on. Anyone heard of anything like this?

yadac123

sensitive is to adjust the tail going in left and right frequently. You want to dial the sensitive down when you are having this. I your tail tends to slowly drift towards a side, you'll need to the use the rudder trim to offset it but there is so much you can do. Would you like me to send you a new motor?

Andy

paulace

Thanks for the offer, Andy, but I'm already on my second motor, and I don't think the problem ever was the tail motor...I think the original motor was probably good. The problem was with the tail rotor linkage all along, I think. And I figured out what the sensitive pot does on the receiver through trial and error. Like I said, it flies well without the fuselage on...it's when the fuselage goes on that the funny stuff happens - that is, the spinning and lack of control of the tail motor. I can't think of what would cause that.