Mustang Prop Arrived

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TXFlyGuy

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The propeller we have all been waiting for just arrived. And it is a beauty!

This new prop really looks the part of the Hamilton-Standard blade design from 1942.

One big reason the production took so long is that Jim Rust (Whirlwind Propeller - El Cajon) is such a stickler for efficiency. He tweaked the airfoil design many, many times in order to get it at what he considers the peak or max efficiency available with the current state-of-the-art.

The diameter, blade twist, pitch angle, were all worked, and re-worked until he hit the "Goldilocks" zone..."It's Just Right".

I admit, it was frustrating for me, waiting for 3+ years to get this. But all of us here (even my wife) are absolutely thrilled with the final product. In combination with the LS376/480, this should be "off the charts" performance wise.

The total weight is 55 lbs, 20 pounds more than the 84" propeller. Gearbox + Prop = 145 lbs. 90 inch diameter. Both the prop, and the hub, are super High-Tech.

E13FE285-BD17-4997-A6CE-C84D637B2BAF.jpg
 

fly2kads

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That's pretty exciting! I guess it's a good thing you started the process a long time ago. Were you expecting the weight difference? That's still a reasonable weight for a prop of that diameter. (Assuming that's four blades?)
 

TXFlyGuy

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That's pretty exciting! I guess it's a good thing you started the process a long time ago. Were you expecting the weight difference? That's still a reasonable weight for a prop of that diameter. (Assuming that's four blades?)
Yes, 4 blades. An MT Prop of that size is almost 100 pounds.
 

pictsidhe

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The first two goals conflict. It's the wrong shape for a very efficient design at your flight speeds, though not as bad as at mine ;)

Mimicking the shape of a Rotol on my Hurricane Mk103 hurt the numbers more than I like. The early DeHavilland is better. Weren't those 'inspired' by Hamiltons? Even better is when I put the DH on a bit of a diet and reduce the blade width a bit more until the gains get small. Mine will be highly reminiscent of a full scale prop, but certainly not accurate. Lacking a V8, I would rather have performance than exact shape...
 
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TXFlyGuy

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The first two goals conflict. It's the wrong shape for a very efficient design at your flight speeds.....Lacking a V8, I would rather have performance than exact shape...
That is the primary reason why it took years to get the propeller designed and manufactured. Jim (Whirlwind) did multiple tweaks on the airfoil. He is a stickler for efficiency, and did not quit until he came up with a design that he was 100% satisfied with.

Looking cosmetically correct was a goal, for sure. You would never put a scimitar blade on a Mustang. And there were many compromises made. Twist, chord, diameter, were all factored in.

In another thread on this forum, nearly everyone chimed in saying that Jim was the smartest guy in the room, God's gift to propeller design.

We are just happy to have a propeller. The timing is perfect as we are soon ready to fly...after we get out of the paint booth (this week).

For more on design, see this: https://whirlwindpropellers.com/aircraft/engineering/
 
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Saville

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Apr 28, 2014
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Boston Ma
The propeller we have all been waiting for just arrived. And it is a beauty!

This new prop really looks the part of the Hamilton-Standard blade design from 1942.

One big reason the production took so long is that Jim Rust (Whirlwind Propeller - El Cajon) is such a stickler for efficiency. He tweaked the airfoil design many, many times in order to get it at what he considers the peak or max efficiency available with the current state-of-the-art.

The diameter, blade twist, pitch angle, were all worked, and re-worked until he hit the "Goldilocks" zone..."It's Just Right".

I admit, it was frustrating for me, waiting for 3+ years to get this. But all of us here (even my wife) are absolutely thrilled with the final product. In combination with the LS376/480, this should be "off the charts" performance wise.

The total weight is 55 lbs, 20 pounds more than the 84" propeller. Gearbox + Prop = 145 lbs. 90 inch diameter. Both the prop, and the hub, are super High-Tech.

View attachment 86182
Sorry just saw this....on what airplane will this prop be going on?
 

TXFlyGuy

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Republic of Texas
Here is another good view of the Ham-Standard. Note how square the blade actually is, looking like a large tongue depressor, or a "paddle". See the data block stenciled near the root. There is a bit of variation here, from plane to plane.

P-51 Glam Gal red nose.jpg
 

TXFlyGuy

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Republic of Texas
Once we do everything possible we can to make it perfect then we can be satisfied if it didn't quite make it.

That's my idea of it anyway.

It's a beautiful prop and I feel sure it's gonna be a real performer.
It should be a great propeller in efficiency, surpassing the current prop in use. Yes, perfection has been the goal, but there are areas where we have fallen short. In the end I'm confident that we will all be happy with the final result.
 
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