View Single Post
Old Oct 10, 2012, 04:30 PM
Alan Hahn is offline
Find More Posts by Alan Hahn
Registered User
Chicago 'burbs
Joined May 2006
1,728 Posts
Originally Posted by Raydee View Post
Alan I am using the standard Trex 700e motor and gearing. Like I said in the post above I know i need to lower the RPM for the gov to work properly. When I put 2200rpm into the program it did warn me but I wanted to try it anyway and make sure.

Do you think when switching to 1950 and having the head speed drop way off before it picks back up is a indicator that the gain is to low?
I'm not an expert on the drop-off issue---I just tend to fly at one headspeed for the entire flight, including takeoff and landing.

I have heard of other's problems with the drop-off. I am not positive what exactly causes it, except that when you flip to a lower rpm, the rotor rpm can tend to decouple from the motor rpm--due to the one-way bearing. So the ESC sees that the motor load drops dramatically and lowers the current way down in an attempt to keep the new low motor rpm--with the motor seeing almost no load. At some point the main rotor slows down enough to have the oneway engage, but now the motor current is really low, so the governor has a long way to go to get it up to sustain the head rpm.

Not sure if that is a real explanation of the problem or not. Sounds good to me !

I am not sure if goosing up the gain will help this or not, and whether the higher gain may cause other problems.

But like I said, it is easy enough to land at any headspeed, as long as you can lower the pitch appropriately. So I don't experience the problem in the way I fly.
Alan Hahn is offline Find More Posts by Alan Hahn
Reply With Quote