The first car tyres were white, not black, as the colour comes from the carbon black that is added to the tyre during manufacture to greatly improve wear and heat dissipation.
The natural colour of rubber is an off-white and the gleaming colour of those early tyres came from zinc oxide added to the mix.
Although they did look stylish they did not have great durability. Read More
Aircraft tyres on a commercial jet are an amazing example of advanced design and manufacture. After all they have to hit the tarmac and after an initial skid accelerate to 170 miles per hour and safely support the weight of a small office building.
But after six months, or 300 landings, they need replacement.
Although some can find further use on farm equipment or backhoes, most are ground into crumbed rubber for use in playgrounds and sporting fields.
Unfortunately, there is a limit on how much can be used for these purposes. Inevitably a large percentage is burnt as furnace fuel.
It was very familiar to Australian car owners in the 50s and 60s, particularly if they had to take the tyre off the rim to repair a puncture.
A tyre with an inner tube was universal in the days when car tyres were made by the bias-ply method.
It was so called because the layers of rubberised cords were embedded in the rubber in alternating diagonal layers at a 55-degree angle to the rim.
But that technology was replaced by the radial method of tyre construction which are steel-belted with the ply cords radiating at 90-degrees to the wheel rim.