The Superjet 100 (SSJ100) combines a high-aspect-ratio wing, fifth-generation supercritical aerofoils and later-developed saberlet wingtip extensions to improve aerodynamic efficiency. The configuration also helped the regional jet meet International Civil Aviation Organization (ICAO) Chapter 14 noise limits with the SaM146 turbofan, which has a bypass ratio of 4.43.
Alexander Dolotovsky, managing director of Yakovlev’s Regional Aircraft division, said the wing’s aspect ratio is close to 10, exceeding the values typically used on regional jets when the SSJ100 was designed. Higher aspect ratios reduce induced drag and can improve fuel efficiency, although the benefits depend on the overall aerodynamic configuration.
The wing was optimised using three-dimensional computational methods in collaboration with the Central Aerohydrodynamic Institute (TsAGI). Its fifth-generation supercritical aerofoils reduce wave drag at transonic speeds by controlling the formation and effects of local supersonic flow over the wing. The SSJ100’s cruise Mach number is 0.78–0.79, compared with approximately Mach 0.75 cited by Dolotovsky for the Embraer 190 and earlier aircraft designs.
Dolotovsky estimated that the SSJ100 consumes 5–7% less fuel on average than the Embraer 190. The comparison was attributed to the Russian aircraft’s aerodynamic characteristics, despite its wider fuselage. The figure was not accompanied by details of the flight profiles, payloads or operating conditions used for the comparison.
The addition of swept saberlet wingtips provided a further improvement in aerodynamic performance. Developed after the initial wing design, the extensions also addressed requirements associated with intended SSJ100 operations at London City Airport. Ireland’s CityJet had ordered the aircraft with plans to serve the airport. Russia’s Federal Air Transport Agency approved the saberlets in December 2019.
The saberlets increase the wing’s effective span and improve its aerodynamic efficiency. Their greater leading-edge sweep helps redistribute aerodynamic loads during high-load-factor manoeuvres, reducing the wing-root bending moment. This approach allows an increase in effective span without a proportional increase in wing structural mass. The extensions also improve take-off and landing performance. Three-dimensional computational modelling was used to select their final geometry. Dolotovsky put the resulting improvement in fuel efficiency at approximately 4%.
The wing design also mitigates constraints imposed by the SaM146’s relatively low bypass ratio. A higher-bypass engine would require a larger-diameter fan, complicating underwing installation because of ground-clearance requirements and potentially increasing structural mass. Yakovlev therefore combined the existing powerplant with aerodynamic improvements rather than relying on a larger engine to achieve the required noise performance.
Dolotovsky attributed the SSJ100’s compliance with ICAO Chapter 14 noise limits to the combination of engine characteristics and aircraft aerodynamics, including its take-off and landing performance. The available account does not provide a breakdown of the individual contributions made by the engine, airframe and wingtip modifications to the aircraft’s certified noise levels.
(No Ratings Yet)
Loading...