9Z and 401 Help / Information

[FyrFtrEmt]

I have been flying for about a year using the 9Z and am now into forward flight. My gyro was setup by someone else and I want to understand it as I am having a little "drift" to one side now.

:oops: I do not understand the difference between the 2 following settings:

1) CND->GYR->DUAL->GAIN 1 = 72% GAIN 2 = 45%

2) CND->ATV->GYR Channel -> RATE A = 72% RATE B = 54%

Can someone explain the difference in ATV and GYR Channel Rates?? ARe they set where they should be or is this causing my "drift" problem?

Is there a place I can find step-by-step instructions for setting up the 401 using the 9Z? The directions stink... :P

Thanks in advance for your help!

[DavidH]

First you should be using the Gyro menu and the ATV's ( Channel 5) to set the gain on the gyro. You can use the gyro menu ( DUO) and leave the ATV's at 100% each side on the gyro channel for each flight condition.
Or you can use the ATV's ( Channel5 gyro)to set the gain and inhibit the gyro program in each flight condition. Pick one of the above methods and use it.

For me with the GY 401 it is easier to inhibit the gyro program in each flight condition. And then set the gain for the gyro with the channel 5 (gyro) ATV in each flight condition. One side of the ATV will be AVCS mode, the other side will be Normal mode.

The DUO mode in the gyro program was basically designed for the GY 502 and 601. You can the GY 401 with the DUO mode, but I have found that most people just use the channel 5 ( gyro) ATV to control the gain with the 401.

Your drift problem is probably not caused by the gain setting. The drift is probably caused by the neutral being different between AVCS mode and Normal mode. Or you did not set up the rudder linkage correctly with the gyro in Normal mode. Also is the subtrims and the trim all set to 0 on the rudder channel in each flight condition?

David

[FyrFtrEmt]

Thanks for the info David!

I guess that's why I was confused. It seems both methods were used when the heli was initially setup and I could not understand why.

I will go this afternoon and use one or the other. I feel certain the trims and subtrims are zeroed...and fairly confident the linkage was setup properly as the drift just started happening.

The servo is mounted on the tail boom, but I will double check the linkage and see if it is correct.

Thanks again for your reply!

[WillJames]

I had a 601 go to drifting very recently. Sometimes I could reset the heli (turn if off and back on) and the drift would stop for the flight. Most other times I could add rudder trim to trim it out. (I know definitely not the preferred way to do things)

It was the Sensor unit. Changed it out and now all iw fixed. :)

Is your 401 in warranty?

[FyrFtrEmt]

I was afraid you would ask the warranty question. I was asking someone at IRCHA about the problem and he told me the same thing. Said the gyro may be faulty. I do not believe it's under warranty.

My brother crashed his Raptor and sent all the electronics back to Futaba for inspection. They charged him $50 for some work on the receiver and replaced his gyro totally!

My luck they would charge $199 for repair...lol!

I may send it in. Was thinking of buying a 50 and selling the 30 complete with gyro and electronics (starting over).

[pilotError]

A rich or lean engine condition could also cause this. If your excessively rich or lean, you will see the tail vibrate (fins shake) and that will also cause the tail to drift.

Mike...

[Dan Lewis]

David helped me get through a similar issue just a few weeks ago! He's very knowledgeable with Futaba. Thanks again David ;)