Space shuttle Discovery is seen after completing its 3.4 mile trip from Kennedy's Vehicle Assembly Building to Launch Pad 39A on March 3, 2010 in preparation for an April 5 launch on NASA's STS-131 mission to the International Space Station.
This story was updated at 12:33 p.m. ET.
WASHINGTON ? The chief of NASA?s space shuttle program said Tuesday that the agency could technically continue to fly its three aging orbiters beyond their planned 2010 retirement if ordered to do so by President Barack Obama and lawmakers. All it would take would be the extra funding needed to pay for it.
Space shuttle program manager John Shannon said NASA spends about $200 million a month on its space shuttle program. That?s about $2.4 billion a year that would be required to keep the shuttle flying beyond their 2010 retirement date, he said.
?I think the real issue that the agency and the nation has to address is the expense,? Shannon told reporters in a mission briefing.
NASA currently plans to retire the space shuttle fleet in the fall after flying the last of four final shuttle missions remaining for this year. The next shuttle to fly is Discovery, which is poised to blast off on April 5 to deliver vital supplies and spare parts to the International Space Station.
The fleet?s retirement would end more than 29 years of U.S. space shuttle flights and leave NASA without a dedicated American spacecraft for launching astronauts into orbit.
Some U.S. senators and members of Congress have expressed support for extending the shuttle program, with Senator Kay Bailey Hutchison (R-Texas) filing a bill last week formally seeking a reprieve for NASA?s space shuttle fleet.
Last month, President Barack Obama proposed canceling the Constellation program building NASA?s shuttle replacement ? the Orion crew exploration vehicle and its Ares rockets ? as part of his 2011 budget request for the space agency. Instead, the president asked NASA to provide more support to private companies that are building commercial spacecraft, which could launch astronauts to the International Space Station.
The 2011 budget request would extend the space station?s life through at least 2020 and set aside $6 billion over five years to spur commercial spacecraft development. The president plans to hold a special meeting in Florida on April 15 to discuss his plan for American human spaceflight.
Shannon said NASA already has the external tank and twin solid rocket boosters for at least one extra shuttle mission beyond the four remaining flights.
That tank and its boosters are currently reserved for a rescue mission in case NASA?s final shuttle flight runs into serious trouble, but could potentially be used to deliver more supplies and cargo to the space station if approved.
NASA has already begun shutting down some parts of the space shuttle program, but could restart assembly lines if ordered to do so. The agency has launched a new study to touch base with its shuttle program suppliers to see what is available and what might be needed to support an extension, Shannon said.
There is also the issue of recertifying NASA?s space shuttles for continued flight beyond 2010.
The decision to retire the shuttle fleet ? which consists of
the Discovery, Atlantis and Endeavour orbiters ? was made in the wake of the tragic
2003 loss of the? space shuttle Columbia and its seven-astronaut crew as they
reentered Earth?s atmosphere.
An investigation board suggested that NASA recertify its space shuttles to make sure they were safe for continued flight if they were to continue launching beyond a planned retirement. NASA planned to mothball the shuttles and replace them with safer capsule-based spacecraft and new rockets to launch them.
Shannon said studies into how best to go about that recertification process have been underway since 2005. The agency has also met with aviation experts for long-running programs, like the U.S. Air Force?s B-52 bomber program, to determine new ways to inspect shuttles to recertify them. ?
After meeting the B-52 bomber experts, NASA added 23 extra inspection points to its shuttle health checks, Shannon said.
?We feel like we?ve addressed recertification,? Shannon said, adding that lawmakers and experts would have to weigh in on NASA?s efforts to make sure they align with the Columbia investigation board?s recommendations.
Shannon said there would be a gap of about two years between the order to resume building shuttle fuel tanks and the time the next one would be delivered. That gap could potentially be shortened by spacing out the remaining shuttle missions, he added.
With the shuttle fleet?s retirement looming amid calls for its extension, NASA has been keeping tabs on the morale of shuttle workers with surveys for technicians and managers every four months, Shannon said.
?From a personal standpoint, I just think it?s amazing that we?re headed down a path where we?re not going to have any vehicles at all to launch from the Kennedy Space Center for an extended period of time; to give up all the lessons learned and the blood, sweat and tears that we?ve expended to get the space shuttle to the point where it is right now where it is performing so magnificently,? Shannon said. ?But it?s a money discussion, and if we don?t have the resources to do that and to continue to logistically supply the International Space Station, then I understand it.?
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