The project to create the Russian medium-haul aircraft MC-21 overcame a key stage - the static tests of the wing. This is reported by Izvestia newspaper.

When approaching near 100% of the design limit load, the wing was destroyed. At the present time, a minor refinement of the wing design is being completed, which will not affect the schedule of the aircraft preparation for the flight tests scheduled for this spring.

As the Irkut newspaper reported, within the framework of the MC-21 program implementation, the final stage of isolated caisson tests of a wing made of polymer composite materials was carried out. The tests were held at the Central Aerohydrodynamic Institute (TsAGI) in Zhukovsky.

"The safety margin of the wing, demonstrated during the tests, allows to begin flight tests of the aircraft," the official representative of Irkut told Izvestiya. According to him, before the tests for strength on the most loaded zones of the structure, the maximum possible and visually undetectable damages were specially marked. In accordance with the approved test program, the wing caisson was brought to destruction.

The MC-21, subjected to a static load, had the most possible weight efficiency, that is, it was as light as possible. Based on the results of the tests, it was decided to carry out a minor revision of the wing, they told source in Irkut. "The overall weighting of the wing design is about 25 kg. For today, such work for the first flight is already close to completion, "the Irkut representative added.