C

Christopher Murphy

Well Known Member
Does anyone here know the exact airfoil that the RV-4,6,7,8 use? I can look at my RV-4 plans for the profile but I don't recall the exact airfoil.

What airfoil does the rocket evo use?

I have been reading about different airfoils ( laminarflow and airfoils with the max thickness at 50 to 60% chord) and would like to compare the qualities of the airfoils used on the faster RV aircraft.

Thanks
Chris M. RV-4
 
NACA 230 Series airfoils

Two-seat RVs except for the RV-9/9A use the NACA 230 series airfoil, specifically a 23012.5 IIRC (12.5% thickness). This is a turbulent flow airfoil.

The RV-9/9A uses a new Roncz airfoil design with enhanced low-speed performance.
 
I was going through that same process recently and stumbled across this awesome list of airfoils:

http://www.aerofiles.com/airfoils.html

According to that page, the RV-3 through -8 all use the NACA 23013.5 foil. I was curious about specs on the EVO wing too, esp. with regard to wing loading, etc., but couldn't find anything online. Other stuff I found useful and cool was the Wikipedia page on NACA airfoils, and Van's description of the RV-10 development process.

Hope that helps.
 
According to my records from 1990 the RV3 is a 23012 and the RV4/6 23015. Not sure about the rest.
tm
 
Christopher Murphy said:
What airfoil does the rocket evo use?
Click to expand...

I understand its the MS(1)-313 aerofoil developed in the ?70s by NASA.

The Evo wing designer told me that this aerofoil has been used on a wide range of aircraft from an ultralight to a 50-seater commuter aircraft. (I think it was also on the 707 and the Finnish PIK glider, but he didnt mention that.) Not only is drag reduced by some 20%, but he views an important feature being the fact that it lends itself to kit plane production since it is insensitive to minor production errors in the wing surface. This insensitivity also applies equally well to insects or rain. At the stall, the lift reduces progressively rather than abruptly, leading to a safer wing from the pilot?s perspective.

That is only what I was told though since I know little of these things.
 
PIK-20 glider..

Steve Sampson said:
I understand its the MS(1)-313 aerofoil developed in the ?70s by NASA.

The Evo wing designer told me that this aerofoil has been used on a wide range of aircraft from an ultralight to a 50-seater commuter aircraft. (I think it was also on the 707 and the Finnish PIK glider, but he didnt mention that.) Not only is drag reduced by some 20%, but he views an important feature being the fact that it lends itself to kit plane production since it is insensitive to minor production errors in the wing surface. This insensitivity also applies equally well to insects or rain. At the stall, the lift reduces progressively rather than abruptly, leading to a safer wing from the pilot?s perspective.

That is only what I was told though since I know little of these things.
Click to expand...

...is a 60's era Wortmann FX-67-K-170 airfoil optimized for the use of positive and negative flaps - it is a thick airfoil designed before the use of carbon fibre spars allowed thinner sailplane wings.

It's the same arfoil as my Mini-Nimbus ot the same era.
 
thanks

That list of aircraft/airfoils is very interesting the 230 series airfoil seems very popular. I read a comment from one expert to the effect that the 230 series
airfoil performs well up to about 400 mph, but I find that hard to believe.

I thought I read somewhere that the -4 and the -8 have different airfoils??
 
The last three digits indicate thickness. So for a 23013.5, the thickness is 13.5% of chord. The -3 is different from the -4,-6,-8 in that it has a thinner airfoil, with the thicker airfoil on subsequent models used to raise the cubic area of the spar, for strength. I believe Van's airfoils are slightly modified 230XX series airfoils, with a slight cuff on the bottom just aft of the leading edge. On my "sport" wing F1, if you put a Van's wing rib to the wing for comparison you can see the difference as this cuff was designed out. I'd be surprised if the cuff makes much of a difference.
 
question

If the thickness( ie 12.5% for the -3 and 15% for the 4,6,7,8) is different then technically they are different airfoils... no? Is the chord length on the -3 less than the others? I guess I could look that up.

I built a set of wings for a biplane once that had an M-6 airfoil. After looking at the 230 series of airfoils the M-6 looks kind of odd.

Chris M.
 
I'm not sure of the thicknesses (12% vs. 15%) but it says right on Van's website that they use:

NACA 230 Series for all 2 seat RV's except the RV9A, which uses a Roncz and the RV10 which was a tailored airfoil of some sort.

I believe the RV3 had the 23012 and the others 4/6/7/8 use a 23013.5 as mentioned previously. A 230 series wing with 15% thickness is a pretty thick wing...

Anyway, I'm not the expert - but between what is on Van's website and what I have laying around here, that's the info I've got.

Cheers,
Stein
 
If it's a customized airfoil, there might not be a specific number for the entire thing. It could be a combination of airfoils from root to tip...I don't know - but I do know who does! Give a call out to Oregon. :)

Cheers,
Stein
 
It's not worth it to bother them.

I was surprised they didn't use the same airfoil as the -9 due to the success that they had with it.
 
I too was a little surprised....

N941WR said:
I was surprised they didn't use the same airfoil as the -9 due to the success that they had with it.
Click to expand...

But I think the bottom line is that the -9 airfoil was designed to aid in low speed characteristics and that was not a factor in the goals for the -10.
 
Mel said:
But I think the bottom line is that the -9 airfoil was designed to aid in low speed characteristics and that was not a factor in the goals for the -10.
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True but the -9 is still very fast for its HP.

Don't get me wrong, Van's did a great job on the -10 and I'm not second guessing them in any way. Just trying to understand their decision making process.
 
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