Whirlwind install - Are all Australians as dumb as me?

I can't work out my whirlwind GA200L prop adjustment.

The manual says to adjust to 20 to 24 degrees.

I set my IPhone with a suitable app to the hub front and pressed zero.
Placed the wooden paddle on rear of left hand blade (horizontal) and adjusted the blade to 22 deg.
I could not get more than 1500 RPM Static
I reducd the blade angle in 2 degree increments until I could achieve 2400 Static - that was 10 times that I adjusted it until my paddle measured only 12 degrees.

Flys great and thank you to all who have recommended this Prop. But what gives with the set up instructions? What am I missing? Did they send me the wrong paddle, can my and my neighbors smart phones be that inaccurate? Is the documentation incorrect?


Curently achieving 2400 static but only 2600 WOT. Does that sound about right. Sure feels good.

Goldy

Colin, I would say that the manual is in error. Your 12 degrees sounds about right. I would reduce the angle until you get 2700 WOT.

How does this prop compare to your old one? Take off, climb and cruise? I suspect that with the lower weight that your trim is more nose down giving you a bit more speed.

Colin, I went through the same thing when I installed my ww prop. That 20 degrees was way off, so I kept reducing the pitch just like you did. I tried using my iPhone 6 with the level app and wasn't happy with it. My neighbor had a new digital level that I used and it worked. I settled on 13.5 degrees, which gives me @ 2300 static and 2750 wot. Because I made so many adjustments the nord lock washers were a concern so I ordered new ones and replaced them all one bolt at a time so I didn't change the pitch setting.
my overall impression of the prop is good. Takeoff performance is about the same but cruise speed at 2450 added 6-8 mph. Fuel burn also is .5 gph higher than before and it's really smooth. I'm sure spending the extra time getting both blades exactly the same pitch is worth it even though I had to replace the lock washers. Larry v.

Well that makes me feel better. I thought I had missed something simple.

Didn't get a lot of time to test the performance as it was quite rough air. But I had installed the carbon fibre floor boards and removed the odesy from the rear seat and mounted the earthex on the firewall. Flew it with the borer and it was very nose heavy and I couldn't fly slow - it was really blowing hard and I couldn't tell but t seemed like my minimum speed was 33 knots. It was not good. So decided to throw the whirlwind on.

It is so responsive. Just rips me of the ground. And with the lower overall weight it just blows the tail up.

My old comfortable cruise was 22 inches 2300 rpm 80 knots. Now at 22 I get 2400 RPM and better than 80 I think but hard to tell in the rough air. But can't get more than 2600 WOT. Not sure why that is.

Also, but it might be my imagination, I feel like I have better vis over the nose when flying? Feel like I am sitting high in the seat.

Larry, I will definitely change out those Nord washers. The prop is not as smooth but I thought maybe it just needs a ballance. Maybe the iPhone is not that accurate.

Thanks guys.

Colin

Interesting that you are at 2300/2750 and I am at 2400/2600. Thought maybe the split would be the same.

I do do have a crapola tach though

cgoldy said:

The prop is not as smooth but I thought maybe it just needs a ballance. Maybe the iPhone is not that accurate.

But can't get more than 2600 WOT. Not sure why that is.

Thanks guys.

Colin

Click to expand...

Try to adjust the blade angle to within tenths of a degree between the two blades. Preferably no difference at all. Blade angle differences contribute to roughness.

The wide open rpm is limited by blade angle being too high. Reduce the angle for increasing rpm and increase blade angle for lower rpm.

Skywagon8a is correct, shoot for 10ths of degrees. My iPhone only reads whole degrees, so that's what I wasn't happy with it. Also the blade horizontal position needs to be exact location during the setting of degrees. My tach is a T-30 digital tach made my Flight data systems and I also have the optical tach check unit verifying the T-30 during testing. The differences in static and wide open of your install vs mine may be contributed to a number of things like temperature, air intake systems differences, exhaust system differences, density altitude etc. bottom line is set your blade angle that's comfortable to you. Larry v.

We've gotten more repeatable results from blade to blade with a smart level that projects a laser beam. We shoot it on to the floor, mark it, and repeat on the next blade. Then get everything tightened up and do it again[emoji1]

I love my panel decal supplier, but his instructions suck, and are confusing too..... https://pulsarprofx.com