The runway at Yakutsk airport was iced over when a Yakutia Airline Sukhoi Superjet 100 (SSJ100) skidded off Oct. 9, Russia’s Federal Air Transport Agency Rosaviatsia said in an Oct. 10 statement.

The runway friction coefficient was rated as 0.45 before the landing—information that was passed along to the pilots. A preliminary assessment in the wake of the incident found the real coefficient was 0.25/0.32/0.25.  “Ice was recorded … which may indicate that the flight field elements are inadequately maintained [at] Yakutsk,” Rosaviatsia said.

Yakutsk airport began a reconstruction project on runway 05R-23L in May 2018. During the reconstruction work, aircraft have been able to use only 2,248 m out of the runway’s total 3,398 m length.

On Oct. 9, the Yakutia SSJ100 exceeded the usable runway length by another 250 m, landing gears were destroyed and principal structural elements of the airframe were damaged as rolled into the part of the runway under reconstruction, the authority said.

In addition, the SSJ100 had an unrepaired technical malfunction, in which the reversing device of engine number two was deactivated. According to the limitations of the minimum equipment list (MEL), landing with deactivated engine reversals is possible only if the runway friction coefficient is not lower than 0.4. After the incident the authority imposed, for the period of runway reconstruction at Yakutsk, a prohibition on flights of aircraft with malfunctions that preclude the use of reversing devices of engines, brake covers (spoilers, interceptors) or wheel brakes of the main landing gear specified in the MEL when landing.

The Federal Air Transport Agency is now considering introducing restrictions to Yakutia Airline air operator’s certificate following the incident.

Rosaviatsia said clearing the SSJ100 from the runway continued for 12 hours, which indicated the airport lacked the necessary equipment and its staff was not trained properly. “As a result, the airport was partially paralyzed; only the departure of aircraft was provided (the airport was closed for receiving aircraft),” the agency said.

Polina Montag-Girmes