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  #1  
Old 08-09-2017, 07:06 PM
cardinalflier cardinalflier is offline
 
Join Date: Jul 2015
Location: Granite Bay, Ca
Posts: 131
Default Hartzell blended airfoil blade

What improvement in speed and climb rate shpuld I expect if I replaced my standard blade Hartzell with a blended airfoil blade Hartzell on my IO360 powered RV6? Thanks
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  #2  
Old 08-09-2017, 07:30 PM
schaplerrh schaplerrh is offline
 
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Location: Alexandria VA
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You should see better climb performance because of your wallet - and thus your aircraft - will be much lighter
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  #3  
Old 08-09-2017, 07:47 PM
6 Gun 6 Gun is offline
 
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Default Prop

Most report 3 to 4 knots. Lots about that to goggle.
Bob
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  #4  
Old 08-09-2017, 08:22 PM
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Larco Larco is offline
 
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Location: DVT Phoenix
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Quote:
Originally Posted by schaplerrh View Post
You should see better climb performance because of your wallet - and thus your aircraft - will be much lighter
Having done it. I agree! 😀
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  #5  
Old 08-09-2017, 08:43 PM
DNeufeld DNeufeld is offline
 
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Quote:
Originally Posted by Larco View Post
Having done it. I agree! 😀
So you are saying having done it you got nothing out of it? How about some help? I am thinking about the same change on my RV6 IO360 standard Hartzell to Blended airfoil.
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  #6  
Old 08-10-2017, 10:22 AM
BillL BillL is offline
 
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https://www.google.com/search?site=&...k1.HW5-vAgPHj0
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  #7  
Old 08-10-2017, 11:07 AM
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FasGlas FasGlas is offline
 
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Location: Idaho ID40
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For what it's worth I swapped out a Hartzell 7666A prop with a 7068 scimitar. Gained vertical and lost horizontal. Not all planes perform the same and different props perform very differently on different airframes. Swapped two props on a Lancair 360 and a Glasair II. Both props were lackluster on each plane as they were. Swapped one to the other and it was night and day for both planes. Only difference was the airframe. I've found that a longer standard prop goes faster than a blended airfoil. There are other factors as well in the mix.
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  #8  
Old 08-10-2017, 12:50 PM
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maniago maniago is offline
 
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Location: Bowie MD
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Quote:
Originally Posted by cardinalflier View Post
What improvement in speed and climb rate shpuld I expect if I replaced my standard blade Hartzell with a blended airfoil blade Hartzell on my IO360 powered RV6? Thanks
I just bought a used -7666. Half the price of the blended which you cant get used. So if you trade up thats 1Kt/$1k. Gotta believe you can spend that kinda money more wisely elsewhere......unless youre racing; then I get it.

BTW theres a guy on here selling a -7666 who had the blades re shaped by Precision Prop in Boise. He claims what hes got is as good or better than the blended. I pinged the shop and they said yes they can reshape -7666s to "better meet your mission" but wouldnt answer my follow on about compared to the blended. In anycase, they said its about 1k to reshape&repaint. Might be worth investigating.
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Last edited by maniago : 08-10-2017 at 12:57 PM.
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  #9  
Old 08-10-2017, 01:51 PM
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rvbuilder2002 rvbuilder2002 is offline
 
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When talking about just a 3 Kt performance change, it is not something that is easy to measure.

It takes many flights done in controlled conditions (absolutely smooth air being one) in both configurations to quantify what actual amount of change it causes.

When the blended airfoil prop was originally being introduced by Hartzell, one was offered to Vans for evaluation. Quite a bit of comparison flight testing was done and in the end a speed increase of between 3 and 4 kts was determined.
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