The Expedition Three crew -- commander Frank Culbertson, pilot Vladimir Dezhurov and flight engineer Mikhail Tyurin -- officially ended their four-month residency onboard the International Space Station on Saturday as the new Expedition Four astronauts moved over from shuttle Endeavour.

Expedition Four commander Yuri Onufrienko and flight engineers Carl Walz and Dan Bursch transferred custom seatliners into the Russian Soyuz escape craft attached to the station and tested the Sokol pressure suits that would be used if the crew has to leave the outpost in an emergency. Those tasks signal the change of "home spacecraft" residency, meaning Expedition Four now lives on the station and Expedition Three astronauts have become shuttle crewmembers for the ride home.

"The seats are all installed," Culbertson told ground controllers at 5:11 p.m. EST. "There's a tiny bit of survival equipment to be installed yet, the medical supplies have all been transferred and swapped and the suit leak checks have all been completed successfully. We'll do a formal changeover later, but in reality, Expedition 4 is the station crew at this point."

The Expedition Three crew was launched to the station August 10. Their stay aboard the station officially began at 3:15 p.m. on August 13. It officially ended today at 5:11 p.m. for an expedition duration of 117 days, two hours and 56 minutes. The total duration of their voyage, including shuttle transit time to and from the station, will be 126 days, two hours and 50 minutes when Endeavour returns to Earth on December 16.

Culbertson, Dezhurov and Tyurin will spend most of the next five days conducting handover briefings with their successors.

"We haven't been able to get into a lot of detail on the systems yet, we've just given the broad brush and the big picture on how things are going," Culbertson told CBS Radio during an in-flight interview. "But the biggest things I'm trying to tell the folks is be patient, you have to be tolerant, both of the people involved and of the equipment itself.

"We're still developing the procedures, still developing the best way to use this hardware, we're still learning about it. It's sort of like we're still in the test flight of an airplane and so patience and flexibility are very important. And of course, you've got to pay attention to details."

While the crew exchange was under way, aboard Endeavour pilot Mark Kelly and mission specialist Linda Godwin used the shuttle's robotic arm to lift the Raffaello Multi-Purpose Logistics Module from the shuttle payload bay and attach it to the station's Unity node. Raffaello was removed from the payload bay at 12:01 p.m. EST and secured in place on the station at 12:55 p.m. EST.

The hatch to Raffaello was opened and the crews began unloading the cargo module just before 8:30 p.m. EST. Over the course of the next several days, the crews will work together to transfer approximately three tons of food and supplies from Raffaello to the station.