A consortium of Alstom and Bombardier is supplying the fleet of 60 trains under a Euros 917m contract signed in 2009. The MI09 is a high-capacity development of the MI2N emu supplied by the same consortium during the 1990s. Each 110m-long train has capacity for up to 2600 passengers (948 seated), and each vehicle is equipped with six large doors to facilitate rapid loading and unloading. Alstom says the improved acceleration and braking performance of the MI09 will allow frequencies to be increased on Line A, where the emus will replace single-deck MI84 trains, boosting capacity by 30%.
The driving cars are being built at Alstom's Valenciennes site, while Bombardier is and assembling the three inner cars of each five-car train at its nearby Crespin works. The trains are being delivered to RATP at a rate of two per month, and all will enter service by 2014. A second batch of 70 trains will be delivered in 2014-17 to replace the MS61 fleet.