Compressed Air Technology - CAT 34 Engine PistonCompressed Air Technology - The CAT 34 Engine

How it works

Our engines have attracted much curiosity and prompted many questions. For various reasons, one of which is industrial secrecy, we haven't published all technical details on this site.

However, over the coming months, just before we begin serial production, we've decided to reproduce an unprecedented amount of information and data on the famous "MDI Air Car".

After ten years of research and development of pollution-free engines and cars powered by compressed air, MDI is proud to present:

Compressed Air Technology systems © : C.A.T's ©(*).

An exclusive technology for truly clean vehicles:

(*) CAT's and Compressed Air Technology systems are registered trademarks of MDI SA

The basic principles of the CAT's 34 Engine

MotorThis engine was developed between the end of 2001 and the beginning of 2002. It uses an innovative system to control the movement of the 2nd generation pistons and one single crankshaft. The pistons work in two stages: one motor stage and one intermediate stage of compression/expansion.

The engine has 4 two-stage pistons, i.e. 8 compression and/or expansion chambers. They have two functions: to compress ambient air and refill the storage tanks; and to make successive expansions (reheating air with ambient thermal energy) thereby approaching isothermic expansion.

Its flywheel is equipped with a 5kW electric moto-alternator. This motor is simultaneously:

No clutch is necessary. The engine is idle when the car is stationary and the vehicle is started by the magnetic plate which re-engages the compressed air. Parking manoeuvres are powered by the electric motor.

The CAT's 34 P04 engine is equipped with patented variable-volume butts and a dynamic variable-volume volumetric reducer.

The dual energy system

The Series 34 CAT's engines can be equipped with and run on dual energies - fossil fuels and compressed air - and incorporate a reheating mechanism (a continuous combustion system, easily controlled to minimize pollution) between the storage tank and the engine.

This mechanism allows the engine to run exclusively on fossil fuel which permits compatible autonomy on the road.

While the car is running on fossil fuel, the compressor refills the compressed air tanks. The control system maintains a zero-pollution emission in the city at speeds up to 60 km/h.

The information contained in this website is based on the 2006 prototypes as seen on CNN and BBC.
Please view the "New" websites below for the most current information.

New: CitycatAirCar.com - OnecatAirCar.com - Got-It-Wrong-On-MDI.com

Catvolution.com - AirCarCatvolution.com - AirCarCompressedAirTechnology.com - GuyNegre.net

2008 NY Auto Show - Please view disclaimer