Russia's state-run Rostekhnologii (Russian Technologies) corporation and Irkut Corporation (part of the state-run United Aircraft Corporation) signed on Wednesday a $3.8-billion contract for 50 MS-21 passenger jets. The contract was signed by Rostekhnologii chief Sergei Chemezov and Irkut's Alexei Fyodorov. The MS-21 is a family of twin-engine jet aircraft still under development by the Irkut and Yakovlev design bureaus, part of UAC. It has a 150-212 seating capacity. MS-21 planes will be produced in three modifications. It will be the first plane with components made of carbon fiber. The new technology will save 25% in fuel and 15% in maintenance costs, as well as reduce harm to the environment.