Wouldn't airplane tires last longer if they were made to spin rapidly before landing?

Answer 1

It may be true for small airplanes that weight is the reason but for bigger planes with bigger tires and more tires, if you spin 18 600+pound wheel/tire/brake assemblies on a 747 to 200mph, the gyroscopic effect of the tires will have disastrous reactions to steering the plane.

That's why the tires are stopped when the plane gets airborne. When the plane gets airborne the brakes are applied to the main gear tires, the nose tires, which don't have brakes, are stopped by a friction pad mounted to the top of the wheel well.

If this weren't true there would be no need for the extra engineering and to use the brakes to stop the wheels and the brakes would last longer and the nose tire would last longer.

Aircraft tires last a very long time. When they are worn, they are retreaded many times. A lot of the wear comes from towing, sharp turns really wear out the tires. When there are 4 tires to a gear, it's hard to turn, the tire actually skids and twists the trucks around a turn, its like trying to turn a car where the front tires are pointed straight ahead.

Answer 2

The wheels are not spinning prior to touch down. They spin on contact with the runway as previously mentioned the puffs of tire smoke you see when an aircraft touches down is from the rubber contacting the runway surface. It does not take long for the wheels to match the speed of the aircraft. Aircraft wheels tires are designed for this contact. As for the spinning on retract... hard to give you an exact number, but if you're ever in a small fixed gear aircraft you will notice they stop quicker than you'd expect and without brakes. The tire rotation on take off is not all that high, and it mostly stopped before the gear retracts into the wells.

Answer 3

For one, aircraft tires are made with 20 or more ply's of nylon cord for the tire body and are very strong, and then the tread which is mostly synthetic rubber. The reason why the wheels don't spin before landing is because it would not let the anti-skid sensors in the wheel do their job properly. These sensors keep the wheels from skidding as the plane touches down, and begins to cycle the brakes on the landing rollout.

Answer 4

There are even more simpler ways to prevent abnormal tire wear on aircraft. For instance, on the KC-10A we ran our tire pressures at 205 +/- 5 psi on the mains, 185 +/- 5 for the nose and 185+/- 5 for the center gear for YEARS, then one day a fellow crewchief decided to do an experiment on his jet and lowered all the tire pressures by 20 psi. We saved an average of 50 tires per year by doing that. The chevron cracking was reduced by approx 40%.

Answer 5

I'm sure an Airliner, back in the 60's or 70's had spinning wheels....driven round by a motor, not spun with the aid of an aerodynamic scoop on the side.
Could be wrong, my memory is not what it once was.

Answer 6

Theoretically yes. However any effective mechanism to match tire rotation to ground speed would be fairly complicated and likely heavy. It's just not worth the extra cost to build, or the extra fuel to lug it around in the plane. After all, if you spun the tire too slow, or too fast you'd have much the same problem.

Answer 7

Yes.

It's cheaper and more fuel efficient to replace tires more often than to add the additional weight, complexity, expense and maintenance needed to fit electric motors to each wheel to spin the wheel on approach.

It's the same answer as all the OTHER times this question has been asked.

Answer 8

Surely not an idea appreciated by the tire manufacturer;-) We may need a device that spins all tires on the landing gear prior to landing. But I had read somewhere that such a device adds more weight to the airplane. It is also not clear on how much of a saving this would bring. This would also affect the aerodynamics of the plane once these wheels start spinning prior to landing.

Answer 9

Actually, some of them are made that way with little cups on the sides of the tires to catch the air and make them spin the direction they be turning when on the ground as it lands. I'm not positive that it is a NORMAL thing. But I did see it on a TV show.

Answer 10

Yes and it has been tried. I don't know the current status but in my cockpit days in the seventies the concern was you landed with spoilers in auto-deploy mode activated by wheel spin-up speed. So if your wheels achieved that rotation your spoilers would go to full deployment while still in the air.

We lost a C-141 as a result of in-flight deployment of spoilers due to wrong auto-select. The memory's a bit fuzzy now but it seems it should have been in RTO, Rejected Take Off but was in Land position.