The crew has already unloaded almost three tons of station food, clothes, experiments and other gear that was launched aboard Endeavour and Raffaello. Early today, the crews had also completed more than 70 percent of the repacking of Raffaello for the trip home, loading the cargo module with trash and gear from the offgoing station crew's mission such as individualized Soyuz space suits and seat liners.
The 10 astronauts and cosmonauts aboard the shuttle-station complex gathered this afternoon in the station's Destiny Laboratory for a formal change of command ceremony as Expedition Three ends and Expedition Four begins. The new crew officially took over duties aboard the station on Saturday. Expedition Three -- Commander Frank Culbertson, Pilot Vladimir Dezhurov and Flight Engineer Mikhail Tyurin -- spent 117 days as the station crew. Expedition Four -- Commander Yury Onufrienko and Flight Engineers Dan Bursch and Carl Walz -- will remain aboard the complex until May 2002.
On Friday, the crews will close the hatch on Raffaello and Endeavour Pilot Mark Kelly will use the shuttle's robotic arm to detach it from the station and lower it back into the shuttle's payload bay to be brought back to Earth. The crews also will continue maintenance work on the station, replacing a faulty air conditioner compressor. Endeavour will undock from the station on Saturday.
Endeavour and the International Space Station remain in good shape, orbiting at an average altitude of 241 statute miles. Last night, the crew and Mission Control noted a transient problem with one of the shuttle's three inertial measurement units (IMUs), the primary navigation units for the shuttle. Only two of the three IMUs were on line at the time, with the third unit off line to save electricity. The IMU that experienced a problem, designated IMU 2, was immediately taken off line and the third IMU brought on line. IMU 2 has operated well since then, but it has remained off line and is considered failed by flight controllers. The loss of one IMU has no impact on Endeavour's mission, and the other two units are operating in excellent condition. Endeavour could operate well on only one IMU if needed.
Endeavour's crew will begin a sleep period at 9:19 p.m. CST today and awaken at 5:19 a.m. CST on Friday.