Tupolev has started cold weather testing on one of its Tu-204SM prototypes in Siberia.
The medium-range twinjet will be subjected to extremely low temperatures at Yakutsk airport.
Ground trials are designed to assess the aircraft's cold endurance after short- and long-term parking of up to 2h and more than 12h, respectively.
Tupolev said this will include testing of engines, auxiliary power units, fuel supply, electric heating and air conditioning systems.
"Preliminary test flights have shown that all this equipment performed within operational parameters," the airframer said.
Tupolev expects to complete cold soak testing of the Tu-204SM shortly, and start its serial production in 2013.