Swept Propellors

[flhrci]

The newest AOPA Pilot has an article about swept propellers. As I understand them, the airfoil is the entire propeller on each side of the hub.

Do I understand this correctly? And if they are so much better, why was this design not adopted in the GA sooner? The improvements mentioned in the article seem to be big. Not practical for a 172 or Piper?

I think I am missing something here.

David

 

[dell30rb]

Link?

 

[flhrci]

Link?

Here ya go...

https://www.aopa.org/News-and-Video/All-News/2013/July/1/Clean-Sweep.aspx

If that does not work for non-AOPA members, try http://www.raisbeck.com/ for the manufacturer website.

David

 

[Velocity173]

Scimitar props have been around since the early 1900's. Kinda like winglets, it's not a perfect design that works in all applications. Best application is multi blade turbo props where you're trying to minimize the noise and drag that come from the tips at transonic speeds.

It seems like the homebuilt racing guys see the benefit running high speed scimitar props. Seen guys put vortex generator tape along the span as well. Lots of tweaking to extract the maximum efficiency from the prop.

 

[Dan Thomas]

Scimitar props have a small constant-speed effect. Under heavy load they twist and the pitch reduces somewhat. Works well in wood, not so good for metal.

Dan

 

[VanDy]

Scimitar props have a small constant-speed effect. Under heavy load they twist and the pitch reduces somewhat. Works well in wood, not so good for metal.

Dan

I was jut going to say they are popular with, and look good on Pietenpols!


-VanDy

 

[Ted]

The big benefit to them, and I think the reason why we're seeing them more today than in years past, is noise reduction. People are getting more sensitive to noise be it because they value their hearing, understand the fatigue benefits, passenger comfort, or because some countries actually have regulations about it.

Count me in the group that wants them. The 310's old school McCauley 3-bladed props are LOUD. Even if new props gave us 0 knots additional airspeed (realistically I think a modern prop should gain a couple knots), if they dropped noise by 5-10 dB, I'd be thrilled.