Farnborough Air Show

MC-21 Flight Tests Continues On Two Prototypes

 - July 12, 2018, 3:00 AM
With two prototypes flying in the program, the MC-21 airliner is attracting dozens of Western vendors, including cabin interior suppliers.

Between the current and previous shows at Farnborough, the MC-21 airliner project made huge progress. A paper bird back then, the next-generation narrowbody jet from Russia’s Irkut is busy undergoing flight tests on two prototypes, with a view to certification next year.

The baseline MC-21-300 will serve as the platform for a family of aircraft. It was designed as a direct replacement for the Tu-154B/M, which had a production run of more than 1,000 from 1972 to 2013. To enhance passenger comfort, the company increased the fuselage diameter from 3.80 to 4.06 meters yet kept six-abreast seating. The standard MC-21-300 accommodates 163 travelers (16 first class and 147 economy), about the same as the older type.

Unfortunately, however, the MC-21 has arrived somewhat too late for its mission. When it acquires type certification in 2019, most airlines that previously operated Tu-154s will have already replaced them with Airbus A320 and Boeing 737 family aircraft.

Yet the manufacturer is confident that its innovative design will perform better than its western rivals and that it will have a production run to match the Tu-154. Irkut claims 175 firm orders (with prepayments made) and 150 commitments. IrAero is the only airline to have signed a direct purchase contract, while Aeroflot, Red Wings, Angara, and Alrosa intend to acquire their airplanes via lessors such as Aviacapital-Service (AKS), Ilyushin Finance (IFC), and Vnesheconombank (VEB).

Along with Iran and North Korea, Russia is under U.S. sanctions under CAATSA (Countering America's Adversaries Through Sanctions Act). As of the middle of last month, it was not yet clear to what extent CAATSA would apply to the MC-21. There are no indications that the U.S. vendors are winding back their participation in the project beyond a relatively small reduction they had in 2014-2015, following the Russian annexation of Crimea. Since the MC-21 comes from the famed fighter manufacturer, logic requires that the West should be interested in seeing Irkut focusing on civilian programs rather than military.

The MC-21 program has attracted dozens of vendors from the West. The UK aerospace industry is involved in the project through work on the cabin interior, flight simulation, parts supply, and so on. United Technologies is contracted to supply 50 Pratt & Whitney PW1431G-JM turbofans. Apart from operable prototypes, these will power at least 20 deliverable examples.

Starting from 2021, customers can choose between the P&W and Russian Aviadvigatel PD-14. So far, 13 of the latter have been completed, and three more are due by year-end. All of these are destined for trials at testing rigs and mounted on an Ilyushin Il-76LL. Since late 2015, the test bed has been flying with an experimental PD-14 on one of the quad’s engine pylons, in lieu of the original D30KP turbojet. The first MC-21 with the indigenous powerplant should fly in the second quarter of 2019.

Milestones Timeline

After a spectacular rollout on June 8, 2016, attended by hundreds of airline representatives and media members, the first operable prototype proceeded to its maiden flight on May 28, 2017. In October 2017, MSN001 was ferried 4,500 km (2,430 nm) from the manufacturing plant in Irkutsk to the Ramenskoye aerodrome near Moscow. After some 40 sorties, the airplane went for maintenance and alternations, a process that lasted until April this year. According to the manufacturer, the flight trials so far cover assessment of takeoff and landing performance, as well as flight characteristics at various throttle settings, involving a critical engine intentional shut-down and re-igniting.

The second airframe is intended for ground testing. In a semi-disassembled form, it was transported from Irkutsk to Zhukovsky for trials at Russia’s Central Aero Hydro-Dynamics Institute (TsAGI). On Christmas Eve, the institute reported completion of the structural tests on MSN002’s all-composite wing box, whose strength measured up to the expectations. Early this year, TsAGI commenced a series of tests on a wing console specimen for mass production, in a number of flight configurations including with retracted and fully extended leading-edge slats.

The second operable prototype rolled out from the final assembly shop and into the hangar of the nearby flight test station in March this year. Apparently, the original schedule saw some delays, which were necessary to introduce design changes following results of the initial testing on the first operable prototype. The second flying prototype flew almost exactly a year after the first one; MSN003 took to the air on May 12 with test pilots Vasily Sevastianov and Andrei Voropayev at the controls. The flight lasted one hour and seven minutes, during which the crew attained an altitude of 3,000 meters (10,000 feet) and accelerated to 216 knots while attesting functioning of control surfaces, landing gear, and various onboard systems.

Work is in progress in Irkutsk on three more airframes, including a pair of fully operable prototypes and an airframe for fatigue testing (MSN005).

In May the plant received a set of wings from Ulianovsk for the first production airframe. If the program proceeds to plan, there is a good chance an MC-21-300 will be at the next Farnborough airshow, in 2020.