French auto runs on compressed air technology

Gear changes are automatic, powered by an electronic system developed by MDI. A computer which controls the speed of the car is effectively continuously changing gears . The latest of many previous versions, this gearbox achieves the objective of seamless changes and mimimal energy consumption.

Safety Concerns

Air powered vehicles have a long history of use in Europe but were discontinued for safety and efficiency reasons. The CATS air cars have undergone stringent safety testing for modern conditions and requirements and appear to have conquered the concerns of air compression engines.

The CATS air tanks store 90m3 of air at 300 bars of pressure (four tanks have a capacity of 90 litres, and they store 90m3 of air at a pressure of 300 bars), just like tanks already used to carry liquefied gases on some urban buses. That means that the tanks are prepared and certified to carry an explosive product: methane gas.

In the case of an accident with air tank breakage, there would be no explosion or shattering because the tanks are not metallic but made of glass fibre. The tanks would crack longitudinally, and the air would escape, causing a strong buzzing sound with no dangerous factor. It is clear that if this technology has been tested and prepared to carry an inflammable and explosive gas, it can also be used to carry air.

In order to avoid the so-called 'rocket effect', this means to avoid the air escaping through one of the tank's extremities causing a pressure leak that could move the car, MDI made a small but important change in the design. Where the valve on the buses' tanks are placed on one of the extremities, MDI has placed the valve in the middle of the tank reducing the 'rocket effect' to a minimum.

Availability

The CATS air cars are at the final approval stage and advance orders are being taken with a release date towards the end of 2004/early 2005.

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