vibration at 4000 rpm
Posted: Thu May 08, 2014 5:24 pm
Good afternoon fellow flyers.
Am hoping one of you can assist me with a vibration issue on my aerie.
I have a Bushbaby taildragger with a Rotax 582 Blue top and E series 3.47 gearbox...both relatively new.
Prop is a wooden 2 blade DeNekker 72" x52...it was recently redone by Oom Pieter..totally refurbished and rebalanced and is 100%..tracking is also within manufacturers specifications.
I also had it balanced on the plane by someone from Rand airport using some fancy equipment.
Everything is 100% and smooth except between 4000 and 4800 RPM...at this rpm I get one hell of a shudder/vibration coming through the airframe.. Its really bad and very uncomfortable.....it feels like when you stick your head out of a car windows at high speed...you get this huge shudder.
Once above or below this RPM, it is smooth again and a real pleasure.
Oom Pieter De Nekker asked me to rotate the prop by a few degrees/ bolts..which I have done...same problem.
Carbs have been balanced using vacuum gauge, plugs changed, new rubbers fitted, etc...
Besides buying a new prop, or finding someone who will loan me a 3 blade warp or similar to compare, and see if its the prop or something else, any ideas as to what is causing this?
has anyone else experienced this with the above setup?
many thanks for your assistance
Joe
Am hoping one of you can assist me with a vibration issue on my aerie.
I have a Bushbaby taildragger with a Rotax 582 Blue top and E series 3.47 gearbox...both relatively new.
Prop is a wooden 2 blade DeNekker 72" x52...it was recently redone by Oom Pieter..totally refurbished and rebalanced and is 100%..tracking is also within manufacturers specifications.
I also had it balanced on the plane by someone from Rand airport using some fancy equipment.
Everything is 100% and smooth except between 4000 and 4800 RPM...at this rpm I get one hell of a shudder/vibration coming through the airframe.. Its really bad and very uncomfortable.....it feels like when you stick your head out of a car windows at high speed...you get this huge shudder.
Once above or below this RPM, it is smooth again and a real pleasure.
Oom Pieter De Nekker asked me to rotate the prop by a few degrees/ bolts..which I have done...same problem.
Carbs have been balanced using vacuum gauge, plugs changed, new rubbers fitted, etc...
Besides buying a new prop, or finding someone who will loan me a 3 blade warp or similar to compare, and see if its the prop or something else, any ideas as to what is causing this?
has anyone else experienced this with the above setup?
many thanks for your assistance
Joe