In August, MC-21 prototype aircraft performed 21 flights with a total duration of 71 hours and 50 minutes, continuing flight certification tests. The main workload fell on aircraft 73057 and 73055; another prototype aircraft participated in separate checks, and the production MC-21 with tail number 73362 was used for the ground program.
In terms of testing pace, August became one of the busiest months of 2026, although it is not a record. In March, three prototype MC-21s performed 31 flights with a total duration of 115 hours and 50 minutes. In February and April, the program yielded 26 sorties each. For comparison, there were 16 flights in May, 13 in June, and 17 in July.
The MC-21 with tail number 73057 worked particularly intensively in August. It performed 14 flights, during which specialists checked the automatic control system, flight envelope protection, ventilation and air conditioning, automatic pressure regulation, and the fire extinguishing system.
Some of the work with 73057 took place not in the air. The aircraft performed taxiing and high-speed runs on the runway. During these tests, the operation of the main and backup braking systems in automatic and backup modes, as well as the nose wheel steering system, were evaluated.
Another six test flights were performed by aircraft 73055. On it, the accuracy of inertial navigation systems, the FMS flight management computer system, radio communication range, and the operation of the automatic direction finder were checked.
One flight was performed by aircraft 73051. It was used to check the radio altimeter.