> > > While flying the airplane, it felt like I was seated inside a bubble of > alumninum foil attached to the back of a giant spinning anvil. > >
I remember reading about ML's experience in an RV6 which sounded very similar. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ List-Post: [email protected] Date: Nov 3, 2007 7:16 AM<http://www.maddyhome.com/krsrch/thread?tt=d&on=4&hit=5> From: Mark Langford <[email protected]><http://www.maddyhome.com/krsrch/thread?tt=f&on=4&hit=5> Subject: Re: KR> Panel Vibration<http://www.maddyhome.com/krsrch/thread?tt=s&on=4&hit=5> Robin Macdonald wrote: > Before you worry about vibration in the panel I think you would be better to > find out where the vibration is comming from & correct that first. You may > be masking another problem. > I'll come over & balance your engine/prop for you. That's a fact! My Corvair is so smooth you can't feel any kind of vibration on the panel...and certainly can't see any! I got my engine balanced at a Corvair College last year. I thought it was smooth before I had it balanced, but there was a real difference afterward. According to his numbers, he reduced it by about a factor of five! That reminds me...I need to do that to this one, although (again) I can't imagine how it could be any smoother. I've done a lot of prop testing lately (several props from other people's airplanes), and one of them vibrated so badly it made me want to land immediately and take it off to prevent damage to my engine. It turns out that engine was properly balanced, but was not aerodynamically balanced (one blade was pulling harder than the other one), and this was made by a "reputable" prop maker! I was at Moontown a few months ago and an RV6 guy asked if I wanted to fly around the patch with him. Sure, why not? When he did the runup it was so rough that I thought one whole cylinder of that IO-360 was completely gone, but he seemed unbothered. We ran down the 2200' grass strip and I thought "surely he'll abort the takeoff, it's so rough", but no, we kept going. On climbout I thought surely we'd land immediately to see what the problem was...but no, he just flew away. I asked "doesn't that vibration make you nervous?". He said "Oh, that's the way all these big four cylinder Lycomings are!" I do know that he's never had his engine/prop assembly balanced, and suggested he do so ASAP. I'm glad I fly behind a Corvair. I guess you have to experience it to believe it. I realize there are no Corvairs in Australia, Phil, so this is not aimed at you. But engine/prop balancing is worth every penny. Just make sure you have your final spinner installed and painted before you do it. Mark Langford, Huntsville, Alabama see KR2S project N56ML at http://home.hiwaay.net/~langford <http://home.hiwaay.net/%7Elangford> email to N56ML "at" hiwaay.net +++++++++++++++++++++++++++++++++++++++++++++ -- Darren Crompton AUSTRALIA My web site: www.kr-2s.com
