NASA will not know if it can achieve the 28 flights planned before the Space Shuttle fleet's retirement in 2010 until the third return to flight (RTF) mission, says deputy associate administrator for ISS and space shuttle Michael Kostelnik.
Fewer than 28 flights would put at risk the completion of assembly of the International Space Station (ISS). NASA's tentative Shuttle schedule assumes three flights this year, then five a year from 2006 to 2010.
The ISS assembly sequence includes the European Space Agency's Columbus laboratory module and Japan's Kibo experimental laboratory module, which can only be launched to the ISS by the Shuttle. The first RTF mission is expected in late May, with the second possibly in July and a third hoped for in the fourth quarter.
"We'll see what we experience on the first and second flights and come the third flight we'll know what we can do. We have flown eight missions [in a year], so we should be able to do five," says Kostelnik.
Source: Flight International
