Wheel Fairing Gap Between Tire

[bgl]

I had a flat tire after 30 hr. I found that the tire had a cut ring all the way around it. It was made from rubbing on the wheel fairing. The gap was made 1/2 in. when I cut out the hole from the start. There was no engine or wings installed at that time when I made the cut out. With the total weight of the plane and fully loaded on take off and landing would bulge the tire and the grove or cut was made. Must have well over 100 touch and go. Replacing two tires and one tube. Made the opening for the tire 3/4 all the way around the tire. I was just thinking The grove may have been made from the bracket for the fairing. Will check tomorrow
Bayne N145Y

 

[Geico266]

I had a low tire at 18-20 PSI that rubbed the side wall, but it good enough to keep, if I keep the tire up to pressure. I have 1/2" gap, need to add more. I did a lot of cross wind landings. The -12 can handle it, if the tires are up to specs.

 

[Tony_T]

Tire Pressure

I have 1/2" fairing to tire clearances and have never had a problem, but I use 40 psig tire pressure.

Tony

 

[Captain Avgas]

Made the opening for the tire 3/4 all the way around the tire.Bayne N145Y

I find that most RV builders have totally insufficient gap between the tires and wheels pants. In the end many of them have eventual problems and then they get smart and open up the gap. 3/4" minimum all around with weight on the wheels is the go.

There's just no real advantage in tight clearances...and lots of potential downside...dangerous downside !!! A local RV guy I know who had the pants too tight caught one during a landing and a piece of the pant broke off, flew up, and ruptured the bottom of his fuel tank.

 

[Bob Axsom]

Why not leave them off?

I made subfairings for the RV-6A that my wife and I build to reduce the drag for racing. There is a lot of superficial thought about these things like fender skirts on a 50s vintage Lincoln and if speed is not important to you, you could just leave them off.

Some of the things I have learned in the past few years with the subfairings:

1 - Tires without smooth & rounded edges are not your friend - Goodyear Custom III works well.
2 - The most vulnerable area is the rear of the opening in the fairing where its edge faces the on coming tread head on. My other three opening edges are very close and actually sometimes touch the tire.
3 - If the intersection of the fairing opening is extended down closer to the ground there is an interesting operational characteristic. When weight is on the wheels the tires push up into the fairing where the "swell out" occurs up in the fairing above the opening, increasing the gap between the tire and fairing and when weight is off the wheels they extend down and reduce the gap which is exactly what you want for drag reduction.
4 - I made special chocks from 1/16"x3/4"x3/4" and rope that I take with me all the time because the chocks at FPOs are much to big to fit,

Bob Axsom

P.S. The subfairings increased the speed of the airplane. There was small gain the the MLG pressure recovery pants but a significant gain from the non-pressure recovery NLG fairing.

 

[Dave12]

I find that most RV builders have totally insufficient gap between the tires and wheels pants. In the end many of them have eventual problems and then they get smart and open up the gap. 3/4" minimum all around with weight on the wheels is the go.

I used the specified clearance and the first time I landed in a good crosswind, the upwind tire contacted the runway and flattened out more than usual due to the extra weight. With 30 psi the tire grabbed the wheel pants on the rear bottom and ripped it. As soon as I heard the rubbing I knew what it was. I repaired the glass and opened the clearance to 3\4" and no problems since.