Veteran NASA astronaut Leroy Chiao will replace William McArthur Jr, KC5ACR, as the commander of Expedition 9, the next mission aboard the International Space Station. NASA says the change in crew assignment resulted from “a temporary medical issue” related to McArthur’s qualifications for the long-duration flight. Chiao will join Russian cosmonaut and flight engineer Valery Tokarev for the six-month mission.
“Because we are very cautious in our approach to crew health, we train backups for this kind of situation,” said Astronaut Office Chief Kent Rominger. He indicated that NASA plans to assign McArthur to another ISS crew increment.
For his part, McArthur expressed disappointment in the turn of events but said he understood the necessity of the medical criteria in place for long-duration space flight. “I know that Leroy will ensure all of the Expedition 9 objectives are met,” McArthur said, “and I look forward to flying soon on another space station mission.”
As a member of the Expedition 9 backup crew, Chiao has been training with McArthur for months. He will also serve as NASA ISS Science Officer.
Since the switch would leave the ISS without an Amateur Radio licensee aboard during the next crew’s tour, it’s anticipated that Chiao will become licensed before he goes into space. The Expedition 9 crew is scheduled for launch aboard a Russian Soyuz spacecraft in April.
European Space Agency astronaut Andre Kuipers of the Netherlands will round out the three-member Soyuz crew. He will return to Earth a week later with the Expedition 8 crew of Mike Foale, KB5UAC, and Alex “Sasha” Kaleri, U8MIR.
An astronaut since 1990, Chiao, 43, has had prior flight experience aboard space shuttle missions in 1994, 1996 and 2000. On his last shuttle flight, Chiao helped to prepare the ISS for its first resident crew.
Tokarev, 51, has been a cosmonaut since 1987. He flew on a 1999 shuttle mission that delivered four tons of logistics and supplies to the ISS in preparation for the arrival of the Expedition 1 crew