Spirit System
https://www.spirit-system.com/phpBB3/

Elevator oscillations
https://www.spirit-system.com/phpBB3/viewtopic.php?f=20&t=3914		 Page 1 of 1
Author:  Almhagen [ Mon 27. Apr 2020 16:02:18 ]
Post subject:  Elevator oscillations
Hi guys,

Recently bought a second hand Logo 700 Extreme with a Spirit Pro gyro. I am having some issues with the heli oscillating about the elevator axis and I can't find any mechanical reason so now I am thinking that it could be the gyro.

The rotor head has been lubed and everything is running smoothly, blades are balance and there are no visible vibrations. I have tried RPMs ranging from 1350-1800 without any luck. I have tried cyclic gain values from 50-70% with expected changes in performance but the oscillations persist. I have also tried different values on the elevator filter and surprisingly 0 seems to work best.

Anyone experience something similar? Any ideas of how I might remedy this?

I don't know if it will work, but I have included a FB link with a video of the heli.

https://www.facebook.com/jesper.almhage ... 69134/?t=0

Thanks in advance!

//Jesper
Author:  ZeXx86 [ Mon 27. Apr 2020 21:31:22 ]
Post subject:  Re: Elevator oscillations
Hello,

please attach your settings so I can help you with a parameter values.

The problem might be in unit mounting - do you use supplied tape? (only single piece)
Another problem could be wrong value for Geometry 6° (likely too high).
But mostly it is caused due to asymetric balance of the rotor head.
Some missing part in the head, blade balancing, too tight blade holders, bent main shaft or any part in the rotor head.
Author:  Almhagen [ Mon 27. Apr 2020 21:47:50 ]
Post subject:  Re: Elevator oscillations
Hi,

Thank you very much for your reply!

Unfortunately I don't have any of the tape that came with the gyro as I bought the helicopter second hand. It is mounted using V-bar Blueline mounting tape that is also very firm.

I'm pretty sure that I had the cyclic right at 6 degrees during the set-up, however, I will go back and confirm this.
Regarding the rotor head, everything is running smoothly. The shafts are straight, blades are perfectly balanced, bearings and dampness are lubed. All components are accounted for. Blades are not too tight.

Please find my settings attached.

Regards,
Jesper

Attachments:
Xxtreme Initial Settings 20200518.4ds [255 Bytes]
Downloaded 31 times
Author:  thestructured [ Sat 02. May 2020 6:47:00 ]
Post subject:  Re: Elevator oscillations
The headspeed is very low in the video - does the problem go away with higher headspeed?
Page 1 of 1 All times are UTC + 1 hour
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/