Searching the internet for wing profiles is like digging for diamonds in your nose... it's very hush hush no one talks shop.

I'm in a lucky position that a close friend builds gliders, so making a wing is not so much of an issue it's finding information that we can throw in a simulation and actually test... Profiles I have found is very draggy, kinda old school and not performing well in our sims...

Was thinking maybe someone here would be willing to share some information. I was hoping to source something closer to that of a APR GT1000, duel elements not an issue, but will need to stick to 2D wings.

 

Google S1223RTL, that is what I used when building mine. Selected by judicious use of the wet finger in the air technique, so no guarantee.

I will be using a COT wing this year, but I don't think anyone has identified that profile in any of the databases.

 

This forum post on Grassroots motorsports mention that the CoT wing uses a LNV109A profile. I think I've stumbled across this more than once now.. that someone said it looks like a Liebeck profile.

https://grassrootsmotorsports.com/fo...g/67922/page1/

 

I don't really know, but I'd guess that on average race car wings are much higher drag than glider wings, so if you are comparing to your friends experience with glider wings they might not be that bad.

 

No no, must have misunderstood me there... Not using profiles from gliders at all... those will never work in a motorsport scenario. He'll be assisting me building the wings and have some knowledge in the area.

Profiles we tested was E420 and I think E424 will need to go and check...

 

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I have seen a post somewhere on MTnet quoting a profile, maybe that one, and saying it is close but there are differences between it and the COT profile. That was the basis for my comment.

For our purposes, maybe near enough is good enough?

 

Yeah definitely, can tweak things once we've determined there is a good profile that someone has used with some success.

What I would love if one the boys on here with a APR GT1000 would trace the profile, scan and share that with me... I'm more than willing to share what I find etc, helps everyone. Paying $2500 for a wing is way outside my grassroots budget.

 

A number of people that I know are using the Selig 1223 profile or an iteration of it.



Remember to analysis your airfoils using Reynolds numbers that approximate the speeds at which you want the airfoil to perform.

 

The graphs produced on that site are really useful, in looking at the range of L/D outcomes and the optimum setup.

As a side note, I found that the wing was upsetting the balance of the trailer when towing at 100-120, and to dial that out meant setting it at several degrees negative AoA; the reason for this was clear looking at the graphs, even at 0* it was still producing appreciable DF.

 

Sweet guys, this is becoming really useful thread... Love it.