It would also save airports from having to scrape rubber from the runays.

This idea was almost an obsession with me. I had the view that you would put a pinwheel on the tire hubcap and thus us the passing air to get the wheel spinning. (Note that even if the speed isn't exactly right, you'd solve most of the problem. The advantage of the pinwheel is that you don't want to add more mechanical systems to the plane. You could also use a spring to store the energy to stop the spinning wheels when the plane takes off.)

It turns out that I had Phil Condit (CEO of Boeing) visit one of my classes and pushed him on this point. His answer was that there were little savings to be had from doing this, but he wasn't able to give any good evidence for this.

Not one to give up, I followed up with the folks at Honeywell who actually make the landing gear. Their explanation was that the tires are amazingly heavy and they weren't persuaded that you would be able to get them spinning just with a pinwheel.

I hope that helps.

A very common question- Bob Crandall of American Airlines claims it adds too much weight for the potential savings- see http://www.desser.com/retreadingp2.html

I think this is a great idea, of course, I do understand the reaction of the industry. However, what if the pinwheel served more than one purpose?

I don't know if airplanes use disc brakes or not, but couldn't the pinwheels be used to brake the plane as well? Instead of adding pinwheels to the current wheel, could the tires be designed with a tread that would cause the wheel to spin?

I had thought this same thing. Why not spin up the tires to reduce the “smoke.” Then I started flying bigger planes and realized the answer immediately. In reality, plane tires are the same as automobile tires. Round pieces of rubber. In your car when you apply the brakes to aggressively (prior to antiskid) the tire skids and develops a flat spot. The same is happening in reverse when a plane lands. It develops a flat spot. Being a pilot flying larger aircraft, I sit right on top of the nose gear tire. After I rotate, if the tire has a flat spot and therefore is out of balance I feel a vibration until the tire stops spinning. If you spin up all the tires from the time the landing gear is lowered to the time the plane is slow on the ground, any tires out of balance (as they are) will vibrate and have the passengers complaining. (This vibration might also have a negative effect on the structural integrity of the aircraft too.)

To add to n6137e's comment above - I've only flown slightly smaller PA28's but have also had the spinning wheel idea as the tyres (sorry - UK spelling !) are sooo expensive.On smaller planes (maybe even on bigger ones?) they paint a stripe over the tyre and inner wheel - and if ever they get out of alignment, the rubber has rotated - usually because of a heavy landing - so the tyre needs replacing. The chance of this happening would be reduced if the tyre was rotating.Your thought about vibrating wheels maybe has a solution - that should perhaps be here as a separate idea...I saw a simple solution to car tyres and their balancing (currently sorted with crude lead weights on the wheel rim). The solution, as ever, was a simple one. If a few ball bearing-type weights were placed inside the tyre, it apparently auto-balances the whole tyre at every speed. I've never seen this idea adopted though - but perhaps now it might be......

This may be done already, it's worth checking out. Where do the ries come from for the jet bridge? Are they new tires? Are they the same size tires used on airplanes? Once tires are not suitable to be used on planes anymore they could have their life extended by putting them on the jet bridge (not as critical of an application). Who knows, maybe that's what they do already.

I recall seeing an invention illustrated in Popular Science maybe 50 years ago: Tires were made with flaps on the side that would catch the wind and spin up the wheel.

I did a Google search on: airplane tires spin land There is an extensive discussion under Google Answers.

hey, thats exactly wht i thought! lol. Well, id guess the fact that the wheels are moving would also make the landing much smoother because much of the "bumps and series of little judders" come from the tires as they are scraped on the ground. The friction caused by the contact of the stationary tire and the ground adds to this. But i think the reason they have not this is becuase it would further increase the stopping distance of the aircraft. The first impact point does reduce the speed quite a bit. Maby this is why?

hey, thats exactly wht i thought! lol. Well, id guess the fact that the wheels are moving would also make the landing much smoother because much of the "bumps and series of little judders" come from the tires as they are scraped on the ground. The friction caused by the contact of the stationary tire and the ground adds to this. But i think the reason they have not this is becuase it would further increase the stopping distance of the aircraft. The first impact point does reduce the speed quite a bit. Maby this is why?

Cessna has a nose spin-up option on some Citation series jets so that they can land on gravel runways with out tearing up the nose tire. The simple reason for not doing it all the time is cost. Any extra weight you have to carry all the time will cost you extra in maintenance and fuel burn. Its cheaper just to replace wheel/tire assemblies as needed than to worry about saving some rubber.

Here's another interesting discussion on this idea by a guy who "invented" it in 1988 and then found prior art to 1942.

http://mb-soft.com/public/planetir.html

As a youngster I always envisioned roads made of rubber and tires made of concrete...no flat tires.