Broken prop or something out of sync. Your ESC board might have a channel that is not providing power at the same rate as the others. If you are hovering, can you hear the flutter smooth out?

When this started the other day, you could only hear the flutter at high throttle.......

After upgrading to BF 3.3 the flutter is almost always there.........

Could this be a firmware issue on the 4 in 1 esc ?

Or hardware failure ?

Problem solved !

I am running the Hobby wing 4 in 1 ESC and Hobby wing FC.

I did not file down the plastic header enough on the 4 in 1 and some of the copper pins were starting to short against the carbon fiber plate directly above it.

My own fault.........
But, the bird is running great now !

Thanks for all the input !

(11-Apr-2018, 01:07 PM)DannyZ Wrote: Problem solved !

I am running the Hobby wing 4 in 1 ESC and Hobby wing  FC.

I did not file down the plastic header enough on the 4 in 1 and some of the copper pins were starting to short against the carbon fiber plate directly above it.

My own fault.........
But, the bird is running great now !

Thanks for all the input !

Good find!!! Glad you hear you are sorted!

Glad you found it, good job troubleshooting. I once had an issue like this on one of mine and what I had to do was break the rules and run it one motor at a time with props on in BF. It has a bottom battery and I held onto it while I spun up each motor separately until I found the offending sound which turned out to be a bearing, it wouldn't do it with props off. Had to hold tight since there was a surprising amount of pull when a prop is spinning.

Hmm I have a 3in with a similar sound. But it's smaller so it's higher pitched and whistles.

I've just ignored it as it flies fine. I've used the racekrafts 3076 and azure 3060. The 3060 flutter less

Hello Danny!

I viewed your upload three times and I think that you are hearing a motor bearing that is on it's way to FPV heaven my friend...
I do not believe that you have an ESC problem, but know that I have been wrong before.

If possible, try what Lorentz suggested. I think he is on to something!


All the best,
FPV4ME

Good catch! And I was wrong again....


All the best,
FPV4ME

No worries fpv4me !
I greatly appreciate any and all suggestions even when I figure something out I still learn things from the suggestions that people make I make a mental note or I write it down on paper because it's going to happen again sometime in the future

I had the same problem with my quad. For me, it was because Self-Leveling mode was not functioning properly. Also, try getting the center of balance right with the battery.