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A blended airfoil fixed pitch

Jerry Fischer

Well Known Member
I visited the booth at Sensenich at SNF and the rep indicated their props from Vans are blended airfoil. However the sight in the accessory catalog doesn't speak to this. I went to Sensenich web site and found no info on blended airfoil...I'm confused.
Jerry
 
Its marketing and symantics Jerry.
Bolting a boat oar to your crank flange and you could call it blended too.
Blended does not have any specific scientific meaning. Its a name coined for a design type but nothing says any prop could not be considered blended. After all, blended is blended right:)
 
Sensenich has a really cool new ground adjustable prop for the 0-200, and 0-235 in a few weeks. It has a cam that you replace and it adjusts the pitch equally on each blade. No protractor needed. You can change pitch in 10 mins.
 
Name does not matter performance does.

I visited the booth at Sensenich at SNF and the rep indicated their props from Vans are blended airfoil. However the sight in the accessory catalog doesn't speak to this. I went to Sensenich web site and found no info on blended airfoil...I'm confused.
Jerry
Any one that has read my prop post, knows I'm a fan of two fan's, Hartzell for constant speed props and Sensenich for fixed.

Proof is in the eating of the pudding. Simply stated the Sensenich is as fast and efficient in cruise as the Hartzell. The Sensenich is MADE specifically for RV's. That is really all you need to know. Nuff said. Don't get hung up on terminology.

What does "blended mean"? You will not find it in aerodynamic text books. Why is it important to you? What is important? Performance.

Obviously the Sensenich is not a direct competition for constant speed Hartzell, its a fixed prop.

Comparing the Sensenich with other fixed props, Sensenich has my vote. Why? Its the fastest and I challenge any one to say other wise. Bring it on, lets do some test.

Sensenich performance is better than other wood props because they are thinner. The Sensenich comes from a large company that will be in business and it can be re-pitched. Lets say you go into a major drag reduction project down the road on a RV you have flown for a while, e.g.: new gear leg & wheel fairings, new wing tips, new cowl or pressure plenum. Now you find your prop is too fine and over Revving in cruise. You can re-pitch it. A fixed wood prop means you must buy a new prop. I also think metal is more durable.

Metal props have negatives like more weight, possible vibration related RPM restrictions. However with a well balanced prop vibration is not an issue. If you want to race around over RED LINE with a hot rod engine, than may be a metal prop might not be for you, fixed or constant speed. For most pilots in typical flying, RPM restrictions is not an issue.

Sensenich did not coin a term like "Blended", but don't have envy. They should call it the RV prop, because that is what it's tuned and optimized for. It's not a generic prop. Like the Hartzell BA, it's made specifically for RV's.

What matters is performance. Van did a Prop fly-off with constant speed props. The Hartzell BA came out on top and the older but still excellent F7666 blade Hartzell did well. They also tested one Sensenich for comparison. At the same RPM in cruise, the Sensenich bested all the constant speed props except the top one or two of them.
 
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Repitch

Wood props can be repitched. We have had several Sterba wood props on RV's and set then back for a slight repitch. I think he does this by reshaping the prop so I don't think you can do too much to it.
 
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