RuAviation

A meeting was held at Rosaviatsia, during which the head of the agency Dmitry Yadrov discussed the aviation incidents that occurred with the management of S7 Airlines. Particular attention was paid to cases of engine failure of Boeing 737-800 aircraft. Rosaviatsia noted that only in the last decade of January three such cases were recorded.

“The investigation of aviation incidents continues. Until the work of the commissions is completed, any other comments are premature. Emphasis has also been placed on strict performance by crews of pre-flight and post-flight procedures in conditions of heavy precipitation at sub-zero temperatures,” Rosaviatsia said. The agency added that statistics for January show that there are no negative trends in the field of flight safety in commercial air transportations by Russian airlines.

As a result of the discussion held on 31 January, S7 Airlines announced a change in de-icing procedures for B737-800 aircraft. Processing on this type of aircraft now takes place exclusively with engines switched off.

“Over the past few days, on a number of flights operated by Boeing 737-800 aircraft, the airline’s crews have recorded changes in the operating parameters of one of the engines. According to flight safety requirements, aircraft commanders immediately decided to return to the parking place for additional inspection of the aircraft by technical specialists. The inspection revealed that the unstable engine operation was caused by contamination of the engine compressor blades due to the ingress of de-icing fluid particles. The effect of contamination is cumulative. It is important to emphasise that in all cases the engine was fully serviceable, the engine itself was not disturbed and the engine performance parameters were within the limits,” the airline said.

In order to guarantee the safety of flights in winter in the presence of precipitation, it is common international practice to treat aircraft against icing immediately before take-off, including when the engines are running. In this case, de-icing fluid may be sucked from the aerodrome surface into the engine. This phenomenon is particularly common on B737 aircraft, where the engines are located slightly lower than on other types of aircraft.

In most Russian regions, the winter of 2023-2024 is characterised by more difficult weather conditions than usual. Due to heavy snowfalls, the Moscow region is already recording a record number of cases of aircraft de-icing needs. Due to these factors, the airline has made changes to the de-icing technology for B737-800 aircraft. At present, this type of aircraft is treated only when the engines are switched off, S7 Airlines explained.