United Aircraft has carried out the first flight of a second prototype import-substituted Yakovlev MC-21-310, advancing the type's progress towards certification.
The twinjet - numbered 006 and powered by Aviadvigatel PD-14 engines - lifted off from the airframer's plant in Irkutsk on 28 October.
United Aircraft says the aircraft will be used to test the powerplants and other new domestically-sourced systems.
It will join the first prototype - a partially-substituted version, which first flew on 29 April - in supporting the MC-21's certification programme.
Four crew members were on board the aircraft for the maiden sortie, which lasted for about 1h and involved the jet reaching altitudes of 3,500m (11,500ft) and speeds of 270kt.
The lead test pilot, Andrei Voropaev, says the aims of the flight had been fully achieved, and all the domestic systems functioned normally.
United Aircraft chief Vadim Badekha says the flight represents a "tremendous amount of work" by the team of designers, engineers and test personnel at various enterprises of state technology firm Rostec.
"To ensure that the new Russian airliners begin carrying passengers as soon as possible, production aircraft are being assembled at the Irkutsk aviation plant in parallel with certification," he adds.
Systems replaced on the aircraft under the import-substitution effort include cockpit controls, actuators, the high-lift system for the wing, stabiliser trim mechanism, various avionics, auxiliary power unit, wheel, tyres and brakes.