Finn Lassen wrote:

Nice flight up, interesting flight back (postponed a day due to bad weather) over
a solid cloud layer most of the way. Really, the noise level at altitude (say
more than 3000') is really not bad.

Can't really say. We didn't do any external comparisons. Do bring your RS sound
level meter! When flying in Tracy's back seat I had on his Bose ANR headsets -
makes a HUGE difference on low frequency noise! I did try to take them off in
flight. It's really hard to make an objective comparison - I'd say his cockpit is
slightly less noisy - maybe. Need that sound level meter.

The biggest benefit from the trip was the results from the prop swap. We both
have Performance Propeller's props. Tracy's a finished 68"x71". Mine is an
unfinished 68"x74" (for some reason I thought his was 72"x74"). I don't know if
I've mentioned it on this list, but at 4500RPM static run up my prop starts
making a highpitched noise and RPM drops to 4200 RPM no matter how much throttle
is advanced. I call it prop flutter - assume prop blade bends-unbends. So at
take-off I keep RPM below 4500 until I've reached takeoff speed and then feed in
throttle. We thought that it might have been a Ross re-drive problem (radial
play). Now we know that it's the prop for sure: does the same thing on Tracy's.
We did note that my blades are significantly thinner.

The most amazing thing is that the difference between 71" and 74" pitch did not
make any significant difference at cruise on Tracy's plane. Maybe a 25 - 50
engine RPM prop (Tracy has the correct numbers). Something is definitely not
right with my prop.

F16? Haven't followed the news. You want the engine?

Finn

 
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