Operators of Let Aircraft Industries L-410s are set to be ordered to fit improved engine control switches to lessen the risk of uncommanded reverse-thrust during flight.

The measures follow the fatal accident involving a Khabarovsk Airlines L-410, which suffered a propeller reversal – a shift in pitch to the beta range – at low height on approach to Nelkan in November 2017.

GE Aviation Czech manufactures the H80-200 engines for the L-410 variant involved, a UVP-E20. The European Union Aviation Safety Agency has previously issued directives requiring inspection and adjustment of the engine push-pull control as well as replacement of the beta switch.

But the engine manufacturer has since developed an "improved" push-pull control, says EASA, which "reduces further" the risk of uncommanded in-flight propeller reversal.

EASA has drawn up a proposed order which will require operators to fit the new control within eight months. It is also setting out an inspection regime for the control at intervals of 100h.

Just one of the seven occupants, a three-year old child, survived after the Khabarovsk L-410's starboard engine entered the beta range and the aircraft, owned by state lessor GTLK, rolled into the ground.

Investigation of the accident turned up several other propeller beta-range incidents involving other L-410s.

Source: FlightGlobal.com