Any comparative speed information on old and new style wheel fairings

Bob Axsom · #1 10-06-2010, 07:20 AM

Have you had both on your airplanes and if so how did they compare in speed? I made subfairings for my RV-6A (nose gear old style, mains new). The nosegear subfairing made a large difference in speed but the mains improvement was not measurable. I have been thinking of making new fairings that will be very similar to the stock and subfairings together. If there is some good information out there I would like to know it before I start making molds.

Bob Axsom

Alan Carroll · #2 10-06-2010, 07:49 AM

Quote:

Originally Posted by Bob Axsom

Have you had both on your airplanes and if so how did they compare in speed? I made subfairings for my RV-6A (nose gear old style, mains new). The nosegear subfairing made a large difference in speed but the mains improvement was not measurable. I have been thinking of making new fairings that will be very similar to the stock and subfairings together. If there is some good information out there I would like to know it before I start making molds.

Bob Axsom

Bob,

Have you looked at the Sam James wheel fairings as an alternative? I've heard various claims that they're faster than the 2-piece Van's fairings (due to being more compact), but no substantiation. I also note that Bruce Hammer has the new-style Van's fairings installed on his very fast Glasair.

Ironflight · #3 10-06-2010, 12:19 PM

Hi Bob,

I'd have to go back into the archives to get true numbers, but we upgraded Louise's RV-6 (kit #4) to all-new gear fairings a couple of years ago and got about 5 knots or so if I remember correctly. That was new pants, gear leg covers, and intersection fairings on a taildragger.

Paul

scottg · #4 10-06-2010, 12:28 PM

Quote:

Originally Posted by Ironflight

Hi Bob,

I'd have to go back into the archives to get true numbers, but we upgraded Louise's RV-6 (kit #4) to all-new gear fairings a couple of years ago and got about 5 knots or so if I remember correctly. That was new pants, gear leg covers, and intersection fairings on a taildragger.

Paul

What style did you upgrade from? I believe there has been three wheel pant styles for the -6, the original one piece, the original two piece and now the two piece pressure recovery. I have the old style two piece and am wondering if it is worth it to upgrade to the new pressure recovery for my -6A.

Thanks,

Scott

Ironflight · #5 10-06-2010, 12:59 PM

Quote:

Originally Posted by scottg

What style did you upgrade from? I believe there has been three wheel pant styles for the -6, the original one piece, the original two piece and now the two piece pressure recovery. I have the old style two piece and am wondering if it is worth it to upgrade to the new pressure recovery for my -6A.

Thanks,

Scott

Original one-piece (hence, kit #4....)

Snowflake · #6 10-08-2010, 10:33 AM

Quote:

Originally Posted by Ironflight

I'd have to go back into the archives to get true numbers, but we upgraded Louise's RV-6 (kit #4) to all-new gear fairings a couple of years ago and got about 5 knots or so if I remember correctly. That was new pants, gear leg covers, and intersection fairings on a taildragger.

Okay, I'm convinced. Now I want to upgrade.

SHIPCHIEF · #7 10-08-2010, 10:46 AM

Dick Martin has a fast RV-8.
I took this pull from the RV builders hotline:

"Want 3-5 more knots? Martin recommends against the Van's wheel pants design. go with the ones designed by the NASA guys, he says."

Who are these NASA guys??? How do we get to see these pants?

Ironflight · #8 10-08-2010, 10:50 AM

Quote:

Originally Posted by SHIPCHIEF

Dick Martin has a fast RV-8.
I took this pull from the RV builders hotline:

"Want 3-5 more knots? Martin recommends against the Van's wheel pants design. go with the ones designed by the NASA guys, he says."

Who are these NASA guys??? How do we get to see these pants?

What is the vintage of the above quote? If it is old enough, he might have been talking about the old-style Van's pants....

And no, I don't know who "those NASA guys" might be....

rvmills · #9 10-08-2010, 11:45 AM

Quote:

Originally Posted by Alan Carroll

Bob,

Have you looked at the Sam James wheel fairings as an alternative? I've heard various claims that they're faster than the 2-piece Van's fairings (due to being more compact), but no substantiation. I also note that Bruce Hammer has the new-style Van's fairings installed on his very fast Glasair.

Alan, any idea if the claims for the SJ's were over the old-style or new PR fairings? I ask, because I have the Sam James pants, and have considered both the new Van's PR pants and the Team Rocket PR pants. In talking with other racers, most feel I won't gain much (if anything) from a switch. However, some have commented on the flat sides of my SJ pants as a negative.

I may gain more by beefing up the glass around the screw holes and using countersunk screws (versus my button-heads), and cleaning up the intersection fairings...but I'm always looking for the next .5 knot!

Thoughts?

And the NASA mystery intrigues me as well...who are those guys?!

Cheers,
Bob

Gerald Loyd · #10 10-08-2010, 07:09 PM

Bob - Last year at Oshkosh Van told me to expect 4 - 6 mph speed increase with the new pressure recovery wheel fairings, so I ordered a set. I did some speed test with my old style fairings on my RV-4 before making the change. After the change to the new style, I got a 3.1 mph increase in speed at 8,000 ft pressure alt. and WOT. Not as much as Van, but I'm OK with it.