Tube tires

[ateamer]

Why do aircraft still use inner tubes and split rims? Is there some particular advantage to it over a one-piece wheel and tubeless tire, or is it just tradition?

 

[Dana]

The sudden spinup when the tires touch the ground tends to spin the tire on the rim, breaking the seal.

 

[Bell206]

Why do aircraft still use inner tubes and split rims?

While it depends on the aircraft, the reason for the split rim is due to the thickness/stiffness of the aircraft tire beads. And if the split rim is not sealed at the halves with a oring or something you need a tube to keep it from leaking. In the past even big jets had tubes. But there are a number of tubeless options out there as well due to certain advantages over tubed tires.

 

[Stewartb]

So guys like us can service tires without special equipment.

 

[Dan Thomas]

So guys like us can service tires without special equipment.

All it would need is a wheel that had an o-ring in one half that sealed against the other half, a slightly different treatment to the valve stem hole for a tubeless stem to seal in, and a tire with a bit more rubber on the inside to seal it.

The biggest factor in such changes is regulatory and bureaucratic inertia and reluctance and the fact that we simply have to buy what's already out there. No competition. The fleet is too small to return the R&D and certification costs. Too much government.

Things would change if Matco, for instance, came up with STC'd tubeless tires and wheels that had nitrile seals for the bearings instead of felt. Champion was feeling the spark plug competition from Auburn so they bought Auburn and shut it down. AC simply started making aviation plugs under the Unison name, which has been taken over by Tempest. If it wasn't for those guys we'd still be endlessly replacing low-time Champs with their bogus resistor design.

 

[Stewartb]

He asked specifically about one piece rims. Grove has O ring tubeless wheels. I wouldn't want them but somebody must. My planes use tubeless tires now, on two piece wheels. Bushwheels.

 

[Mooneys R Quicker]

Back in the day we used race go karts that had the two pice rim with the o-ring in the middle. We only ran about 8 to 12 lbs of tire pressure , but every week our tires would be down and even sometimes flat. We even tried sealing the halves with silicone, sometimes it worked sometimes it didn’t.