Quad does the boogie when coming down...

[Hionimi]

Heya, support has been awesome on this forum, so I'm going on ahead and shoot another question.

My Quad shakes quite violently when coming down, spectators always go: "Go higher!" And I don't mind making them happy, but when I wish to get the Quad back down again, it shakes eerily violent. Could this be a bad I-gain setting or just a limitation of the Flight Controller? I haven't tested it with Auto-level off by the way, maybe it could be that?

 

[xuzme720]

It's from the propwash..try moving laterally as you drop instead of straight vertical. You have to get away from most of the downwash of the props as you descend. Like come down in a diagonal instead of straight down. I don't know if I'm making sense.

 

[Hionimi]

Ah, thanks, makes sense the way you explain it, will try out your tip on the next run.

 

[Cyberdactyl]

And I don't know if you are using them or not, but three-bladed props are much worse regarding prop wash.

 

[Tymtravler]

I agree with Xuzme this action is know as "Settling with Power or the Vortex Ring State". As an R22 helicopter pilot this is a very dangerous condition that can slam a copter into the ground. As soon as you observe the copter starting to shake just apply some forward cyclic to stop the problem to get out of your own thrust. Now you can do a maximum performance landing where you can come straight down but you must descend very slowly to prevent SWP.
Hope this helps