Perry Mick wrote:

Here is a photo of my new prop. It has a tapered hub, that will form

part of

the "spinner". I finally got the dynamic balance worked out yesterday,

but

it's been too foggy to fly. Hopefully I can take it up tomorrow and

see what

it will do.

Perry

Thanks for the report Perry. Any data on cooling for the first flight?
Does this engine have rubber motor mount?

Paul Lamar

Ambient temps have been cool. The two flights I did so far were too short. I
was concerned about ground cooling, but it did survive a taxi to the runway
+ wait for traffic + high speed taxi test + taxi back + long wait for
traffic + takeoff with no abnormal temps so it might be ok. The "big fan"
might do a better job of sucking air through the rad than the little fan
could with no fanduct.

I have the parts cut out to make the new motor mount, but haven't done it
yet. It's difficult to take the plane down, would rather keep flying. When I
do build it, I will raise the thrustline back to normal, probably add a prop
extension, and then will have to make a new cowl.

Perry

So for the new people Perry has been flying for years with the engine bolted
solidly to the air frame. The wankel is that smooth.

Paul Lamar

I think that works with a direct-drive fan, but it's definitely not the
way to go with the prop and gearbox. The prop is now balanced, but there
is still strange vibration at certain RPMs associated with the gearbox.
I will have to take the plane down soon to build the new mount with
rubber bushings. Good thing it's wintertime.

I snuck in a quick flight this evening before sunset. Temps got pretty
high on climbout on a cool day, so cooling is worse. But I'm making a
little more power. Climb rate is better, 1300-1500 fpm vs. 800-1000. I
throttled way back and let it cool off a bit. Leveled off at 3500 feet,
didn't go full throttle, but took it up to 5800 RPM (2670 prop, 252 fps
ideal 68" pitch = 172 mph), indicated airspeed 140 knots, GPS ground
speed 150 knots (173 mph, what a coincidence!). This is faster than it's
ever been. It was running hot in that realm too, so I definitely need
that double-decker rad now.

 
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