Russia's leading aerospace companies Irkut and Sukhoi have agreed to co-ordinate the family planning of their airliner programmes as part of a joint development effort on the MS-21 next-generation twinjet under the United Aircraft (OAK) umbrella.

The move will enable Sukhoi to develop its planned 110- to 130-seat stretch of the 95-seat Superjet 100, dubbed the SSJ-110/130, which will incorporate an all-new composite wing, as Irkut is dropping the planned smallest member of the MS-21 family, the 130-seat -100. It is making the 180-seat MS-21-300 the baseline model with a stretched 210-seat -400 also proposed.

Sukhoi is to take on responsibility for the development of the MS-21's composite wing as a scaled-up version of that of the SSJ-110/130. Irkut's Yakovlev design house will create the drawings for the MS-21's welded aluminium fuselage. Beriev will draw the composite tail cone and empennage.

While the revised plan enables Antonov and Tupolev to be re-invited to join the MS-21 programme “on new terms”, Irkut president Oleg Demchenko says that the hoped-for international co-operation has so far drawn a blank as long-held negotiations with preferred partner Airbus have failed.

“Airbus is overloaded with A380, A400M and A350 work, and we cannot wait until 2010-11, as they asked us, for the MS-21 development,” he says.

This year Irkut will receive 1.6 billion roubles ($68 million) in state funding for the MS-21 and another 1.9 billion roubles in 2009, but Demchenko expects research and development will require "twice this amount".

The MS-21 is due to receive "concept approval" in August, to allow preliminary design work to start in September when system suppliers - both domestic and foreign - will be invited to tender. Supplier selection is due to be completed in 2009. MS-21 series production is due to get under way at Irkut's IAZ plant around 2015.