Vibration when flying

Sv.grainne

Super Member
Joined
Jan 14, 2020
Messages
1,173
Location
Kerrville, Texas
We are test flying my Aviomania Genesis and Eric had noticed a vibration at 4200-4600 RPM. What are some suggestions on how to narrow this down? I'm thinking best to start with prop pitch, repitch a small amount and see what that does. I do not have access to a prop balancer. Others have said that some vibration at specific RPM ranges is common.
 
Last edited:

Mike G

Junior Member
Joined
Jun 16, 2005
Messages
1,704
Location
Lillebonne France
Aircraft
Owned Magni M16 now ELA 07
Total Flight Time
550FW + 500 gyro
How did you/Eric arrive at 4200-4600 rpm?
I think you have a 912, so prop imbalance would be nearer 2000 rpm and the blade passing frequency would be around 6000 rpm (assuming 3 blades) so I doubt if it's the prop.
If the 4200-4600 is engine rpm then look at carb balance especially if the vibration reduces with higher revs. If not out of balance crank (unlikely) or engine mounts.
Mike G
 

Sv.grainne

Super Member
Joined
Jan 14, 2020
Messages
1,173
Location
Kerrville, Texas
Readjusted prop, took 1deg off, ran it up on the ground, 5580rpm WOT, no vibration. Eric will fly next week and see if that changes anything.
 
Last edited:

Aerofoam

Active Member
Joined
Dec 2, 2020
Messages
230
Location
Az.
Aircraft
Pteradactyl, AC 447/503, too many UAVs
Total Flight Time
Over 3k....(From the ground !)
Readjusted prop, took 1deg off, ran it up on the grounds, 6580rpm WOT, no vibration. Eric will fly next week and see if that changes anything.

I've got a couple you can come balance......
 

Tyger

Super Member
Joined
Nov 25, 2017
Messages
2,017
Location
Clermont, NY
Aircraft
Magni M16
Total Flight Time
475
You corrected it, so nothing to comment on... but what "response" are you talking about?
 

Greg Vos

Active Member
Joined
May 26, 2019
Messages
517
Location
Cape Town
Aircraft
R44/22 H269/300 MD 500 Magni (all); Xenon RST; DTA; ELA; MTO Trojan
Total Flight Time
Stoped counting at 2000
I’m chasing down a damn cabin hop in my xenon gyro 😡 can I get it better?

 
Top