MС-21 prime contractor Irkut is performing windtunnel tests on the wing/engine combination for the new 150-212-seat twinjet family in development by Russia’s United Aircraft.

The work, carried out at the Central Aerohydrodynarnic Institute (TsAGI) in Moscow, includes a subscale wing and engine combination used to determine critical flutter velocity as a function of engine pylon rigidity, aileron input rate and fuel loads.

The wing section, built by TsAGI, was outfitted with miniature accelerometers and strain gauges to record wing mode shapes and bending and torsion loads. The data will be used to update the aircraft mathematical model to better design against flutter and other aeroelastic phenomena on the full-scale aircraft, says TsAGI. Windtunnel tests were completed in October at TsAGI for the aircraft’s high-lift devices during take-off and landing conditions. Also in October, TsAGI acousticians completed experiments on a system of “mini-cowls” on the nacelle nozzle that officials say “exceed by twice” the efficiency of currently available systems. Landing gear and cabin internal noise were also studied.

The 150-seat MС-21-200 is the lead variant, which is due for certification in 2016. Western engine makers Pratt & Whitney and Rolls-Royce are among the candidates competing to supply the all-new twinjet’s powerplant.

Source: Yakovlev