In Russia, during the import substitution of composite materials for the wing of the MC-21 medium-range aircraft, a heavier structure was obtained, which led to a decrease in range and performance, effectively returning the project to the level of Soviet airliners. This was stated to "Perviy Tekhnicheskiy" by aviation expert, board member of the Association of Small Aviation Enterprises (MalAP), and founder of the flight safety service RunAvia, Andrey Patrakov.
According to him, the aircraft project now needs to be redone properly, but the costs for this are too high, and the main "feature" will be lost.
As a result, the current version in terms of characteristics would roll back closer to the level of the Tu-154: transporting approximately the same number of passengers and to the same range.
Patrakov suggested that it would have been easier to make a metal wing for the MC-21 with less loss in characteristics. Now, the extra weight is "exchanged" for fuel — the aircraft will be able to carry less kerosene and, accordingly, fly a shorter distance.
Anatoly Gaidansky, Director of the Yakovlev Engineering Center (part of the Rostec United Aircraft Corporation), noted that the MC-21 is planned to be made 15–20% lighter; for this, Russian engineers are using thermoplastic composites. This approach will significantly improve the aircraft's fuel efficiency and operational characteristics.