Tata Motors, once derided as the company with a name that sounds like it ought to be spread on a Fillet-o-Fish, has been making some serious forward movement in the past year or two.

Now, hot on the heels of its recent acquisition of Land Rover and Jaguar, and news of the impending assault on the European market with the Tata Nano, the Indian company is set to release a car powered entirely by air. But is it all hot air? (You see what I did there.)

Turns out it`s very much a legitimate prospect. Sure, it looks bloody ordinary, but let`s look beyond the styling for the moment. The MiniCAT (Compressed Air Technology), invented by French madman and ex-F1 engineer Guy Negre and his company Motor Development International (MDI), is a lightweight fibreglass urban car built around a tubular chassis which is glued together rather than welded. More importantly than that, and as you`ve no doubt gathered, it`s powered entirely by compressed air.

Around 6000 of these zero-emissions Air Cars are planned to blow onto Indian streets by August 2009.

Tata`s Air Car, which MDI calls a MiniCAT, is expected to cost the equivalent of $8177 in India, and would have a range of about 300km between refuels an event which, due to the fact you`re only paying for the power needed to work the compressor, would cost around $2. Until the market for this car is properly developed though, owners will find included a small compressor which can be connected to any regular power supply, and will refill the tank within 3-4 hours.

If all that weren`t enough, the Air Car`s lack of a combustion engine means that the need for regular oil changes is a thing of the past, as new oil is only needed every 50,000km. That`s one very welcome extra zero on the end.

Here`s some nifty bullet points

The Air Car runs a specially developed piston engine that uses a new thermo dynamic cycle offering exceptional energy efficiency.

Compressed air is stored in carbon fibre tanks, at 300 bar (4,351 psi).

The CAT engine operates on four cycles: intake and compression, combustion, expansion, and exhaust.

Outside air is drawn into the compression chamber and compressed to 20 bar (290 psi). At the highest point of pressure (at `top dead centre`), this air reaches 400 C (centigrade), and, at that point, air from the storage tank is injected into the combustion chamber.

Since the injected air is much colder than the compressed air in the chamber, the injected air is heated instantaneously, causing a sudden expansion, which pushes the piston down (in an expansion stroke)

The air tanks fitted to the underside of the vehicle can hold 300 litres of compressed air, capable of driving the MiniCAT for up to 200km.

Using a household electrical source, it takes about 4 hours for the vehicle to refill its own compressed air tanks (a rapid three minute recharge is possible using an external high-pressure air pump.

The MiniCAT runs an electronically controlled continuously variable transmission (CVT)