The final nighttime search and rescue drill for the landing of the Shenzhou VI spacecraft concluded last night.

The spacecraft was launched on Wednesday morning on a five-day flight, with landing expected on Monday morning. However, the length of the flight could be affected by weather at the landing site and other factors.

Four helicopters took off one after another at 6:40pm yesterday from the main landing field for Shenzhou VI to begin nighttime search and rescue drills.

At 8pm, the first helicopter landed less than 50 meters away from the presumed location of the re-entry capsule.

At 8:02pm, staff of the search and rescue team helped two "astronauts" open the door of the re-entry capsule. The astronaut stand-ins walked out of the capsule unaided.

At 8:05pm, the two "astronauts" boarded a helicopter on their own to go through a medical check-up.

At 8:32pm, they boarded two helicopters and were flown to a transfer airport, wrapping up the drill.

The exercise, which started at 6:25pm, aimed to enhance search and rescue capability to ensure the safety of the astronauts.

Earlier, three such drills had been held in the main landing field located in the central part of north China's Inner Mongolia Autonomous Region.

Wu Guoting, a member of the manned spacecraft expert panel of the Chinese Academy of Space Technology, said the return time of Shenzhou VI is influenced by weather conditions.

"Weather conditions at the landing fields are very important. We will adjust the time of the return according to the conditions of the landing fields and conditions of the flight," he said.

The flight is planned for five days, but the spacecraft has enough supplies for a seven-day journey, in case the landing must be postponed because of weather.

According to weather report, the lowest temperature in the main landing field was five degrees below zero. Westerly winds were at a force of 4 to 5.

Temperatures will begin to rise today and tomorrow, but drop on Sunday and Monday.