Calculations of the characteristics of the Russian MC-21 aircraft showed that its practical flight range, based on the parameters from Sberbank's presentation, could be significantly higher than the stated values. This conclusion was reached by aviation expert and author of the Skyexpert channel, who independently verified the published figures using basic calculations.

The author compared the initial design characteristics of the MC-21-300 with Pratt & Whitney engines and the parameters of the import-substituted version, as presented in Sberbank's presentation. The initial data used were a maximum takeoff weight of 85 tons, an empty aircraft weight of 49.4 tons, a commercial payload of 17.5 tons, an hourly fuel consumption of 2.8 tons, and a cruising speed of about 850 km/h.

After calculations, the expert found that with a fuel reserve of 18.1 tons, the aircraft can stay in the air for about 6.5 hours, which corresponds to a range of approximately 5500 km, excluding mandatory reserves. After deducting the air navigation reserve and fuel for an alternate airfield, the practical indicator is estimated at approximately 4800–5000 km.

The author emphasizes that he does not claim absolute accuracy of his own calculations. His goal is to check the internal logic of the published data. According to the expert, if the parameters from the presentation are taken as initial, the calculated flight range turns out to be significantly higher than the 3800 km stated therein.