OneCAT (Compressed Air Technology) was advertised as an upcoming compressed air car in 2008. India's Tata Motors was said to be collaborating with Air engine developer Guy Nègre of MDI to produce the vehicle.
The vehicle contains air tanks that can be filled in four hours by plugging the car into a standard electrical plug. MDI also plans to design a gas station compressor, which would fill the tanks in three minutes.
The OneCAT is a five seat vehicle with a 200 litre trunk. There is no reliable data on range and top speed for this prototype available.
As of August 2009 there was no mentioning of the prototype or planned production of the TATA OneCAT on the TATA or MDI homepages. In December 2009 Tata's vice president of engineering systems confirmed that the limited range and low engine temperatures were causing difficulties. Meanwhile all links, articles and archives relative to MDI have disappeared from Tata's website.
In February, 2012 Tata released information that their compressed-air vehicle would debut in August, 2012. 
- "Tata OneCAT, compressed air car at Rs 2 lakh price, Tata OneCat photo, picture gallery". Dancewithshadows.com. 2008-02-19. Retrieved 2010-02-24.
- Harrabin, Roger (13 February 2008). "Five-seat concept car runs on air". An engineer has promised that within a year he will start selling a car that runs on compressed air, producing no emissions at all in town. (BBC News). Retrieved 2008-02-16.
- Note: All the figures are from MDI and are not independently verified
- "TaMo's ambitious 'Air Car' faces starting trouble". dnaindia.com. 2009-11-25. Retrieved 2010-02-24.
- Tata Motors
- CyberMedia.com/Aircar Portal and fan site on MDI air-car.
- CATvolution.com - a fan website
- The OneCAT at the 2008 NY Auto Show on YouTube - from CATvolution.com