Crashing and cant figure out why

[collegeboye]

http://helifreak.com/images/icons/icon1.gif Crashing and cant figure out why
Hello
I bought a used Raptor 30 from a guy about 3 months ago. It came with radio, jr500 ring gyro, and ready to fly. I flew if as is for about two months but decided to upgrade the radio to my DX7 once I was used to the heli. I also put a o.s 37 in it since it had a .32 in it. Once I installed everything, I took it out for a test flight. The heli felt like a new machine. The responce even seemed quicked. I broke the .37 in and began to do some sport flying. On a landing approach, the heli started to slowly to the left without and input and It didnt respond to my inputs. All other inputs seemed to work, as I attempted to punch out of the landing. Only the tail didnt respond. Long story short, I crashed.:mad: gave it a quick look over and the tail servo was responding to my inputs just fine.

I finally got it back together today and decided to take it out. Flew a few tanks and she flew pretty good. After my third refueling, I began a slow lift off and the heli started to turn nose left again with no input. Clicked it in throttle hold and attempted to bring her down but it didnt go so good since the heli had a nose down attitude.

The same thing is causing me to crash but I dont know what it is. All servos seem to work fine, Engine is running good and the gyro holds great except for these few instances. Can some one please help. Its getting pretty dang expensive buying new blades and replacement parts.

What could cause this?:arggg:

[vandelescrow]

perhaps a defective receiver.

[collegeboye]

I hope not. Its a AR7000 and its a hundred bucks on top of repairs. thanks for your input

[forjer]

I've got a couple friends that tried old or cheap gyros with disastrous results. You may want to consider a new or newer gyro. Futaba GY240 is a good start. Of couse yoy can't go wrong with a GY401 and a nice digi tail servo or a Spartan. Stay away from the ring gyro.

[collegeboye]

I think I may go ahead and get another 401. I have one on my t-rex 500 and it holds great.

[Raven_darkcloud]

It sounds like gyro drift. 401 will do you good.

[vandelescrow]

Oh sorry, I read your original post wrong, I thought you said none of your servos were responding when you crashed.

Possibility. Not sure on what equipment you have so bear with me. If you have a gain wire for your gyro, it is probably just 1 wire in a plug for 3. This may not hold tight enough in your receiver and fall out due to vibration. You can try a short servo lead extension from your receiver, plug the gain wire into it, and tie the connectors together so they can not come undone. I've seen in a few magazine articles where people use dental floss for this.

[MXRACERX43]

What kind of headspeed are you running? Also your gaun settings. What about your throttle and pithc curves? You may be lifting offf with to low of a throttle point causing your headspeed to be to low. This would cause your tail to loose holding authority. Same thing may be happening on your landing aproaches. You need to keep a constant headspeed on decents in N mode.

[collegeboye]

Head speed may be the problem. I just chaged to the DX7 and had to redo all of the curves. I dont have a tach yet but I never had the problem before with the old radio/reciever. It did only happen when I was lifting off and landing too so that sounds very reasonable. Too bad I just ordered a new 401 servo combo for the think. As soon an I get it together I will see if head speed is too low. I met a local guy who has a tach. Thanks for all of the replies guys. If it werent for you guys I would probably quit the hobby and just stick with R/c cars and riding my Hayabusa as hobbies.
You guys rock:Bang