Sukhoi Civil Aircraft Company (SCAC) on Thursday signed a letter of intent (LOI) with the S7 Group calling for delivery of up to 100 of the recently revealed shortened derivative of the Superjet 100 called the SSJ75. While meeting at Turkey’s Eurasia Airshow this week, the sides declared their intent to conclude a firm contract by the year-end. The deal would involve 50 aircraft plus options on a further 25 and purchase rights covering another 25.

The SSJ75 would seat 78 passengers in a single-class cabin configured with a 32-inch seat pitch or 88 passengers at a 28-inch pitch. SCAC plans first flight of the development prototype in 2021. Plans call for the manufacturer and certification trials to involve 1,000 flights with three aircraft. Developers plan to assemble one more airframe for ground testing. 

According to the LOI, first shipments would happen in 2022, but SCAC CEO Alexander Roubtsov explained that after the planned completion of the flight testing in that year, “most aircraft” in the initial batch would go to the defense ministry. Shipments to “commercial structures” would commence in meaningful numbers in 2024-2025.

“Addressing the sector of regional air traffic is very important for the airline and the group,” S7 Group general manager Anton Eremin stressed. Basing plans on experience out of the carrier’s main airport in Novosibirsk, S7 Airlines wants to further develop its hub-and-spoke operations to ultimately cover the whole of Russia with regional routes served by small jets. “It is a very challenging goal we set before ourselves,” said Eremin. “Requirements from the side of the economics are very demanding, more so than those to operations on narrowbody jets. Suitable regional jets should offer very good operational economics to ensure the regional services are profitable, while the aircraft shall be reliable in operation and easy to fly even for novice pilots.”

Eremin further noted that the system S7 plans to establish would more closely resemble that of Soviet times, when airlines employed a combination of the 160-seat Tu-154 and 75-seat Tu-134. Accordingly, SSJ75s would supplement the carrier’s larger Airbus A320 family jets.

The SSJ75 will keep the same cross-section as on the SSJ100, thereby meeting customer requirements. Roubtsov called SCAC’s plans “the widebody approach” to regional jetliners. He conceded that the SSJ75, with its wide fuselage, might look “somewhat extravagant,” but airline customers insisted on five-abreast seating and overhead baggage bins “similar in size to those on the A320 and 737.”

For a reduction in structural weight, the fuselage will consist of aluminum-lithium alloys, which have been used in other Russian airliner programs. A redesigned, composite wing will feature a smaller area but higher aspect ratio for a 10 percent increase in lift-to-drag ratio. Using new construction materials would reduce structural weight by 10 to 15 percent, chiefly through an increase in the share of composites from 8 to 10 percent up to 40 to 45 percent.

Powerjet SaM146 engines, now used in the SSJ100, would also power the SSJ75 but with “modifications,” but Routsov added that as production unfolds, SCAC will be looking to employ more modern turbofans with a higher bypass ratio, targeting a 7 to 8 percent reduction in fuel burn. Options include Pratt & Whitney’s GTF and the Aviadvigatel PD-7, a derivative of the PD-14 developed for the MC-21 narrowbody.

The SSJ75 would have “much in common” with the MC-21, for which SCAC will contract with an Irkut team to work on the new Superjet, he added.

Plans call for the SSJ75 to use 20 percent larger windows than those on the SSJ100 and incorporate “modern solutions for Internet on board.” It would need to operate from short airfields, from between 4,265 and 4,600 feet in length, and be capable of landing on runways with a pavement classification number of 18.

Although the Kremlin has promised to provide funds for SSJ75 development, its commitment comes with a demand for a functioning cost-control system from SCAC. It also requires that the new project ensure that the investments made at its early stages would pay dividends within a “reasonable” time frame. The government has also pledged to provide guarantees for residual value of used airplanes. “Lessons shall be learned from the SSJ100 experience,” concluded Russian deputy minister for industry and trade Oleg Bocharov.