NASA has made steady progress toward the planned retirement of its three aging space shuttles this September, but will likely not complete the fleet's current flight schedule until February 2011, a new report has found.
The 32-page audit was released by NASA's Office of the Inspector General, the agency's financial watchdog, on Thursday — one day before top space shuttle officials planned to meet at the Kennedy Space Center in Florida to discuss plans for the next shuttle mission, which is slated to blast off on April 5.
"Based on calculations by the Office of Inspector General, historical flight rates, and internal NASA evaluations, NASA is not likely to meet its September 2010 timetable, and it will most likely take until the second quarter of FY 2011 to complete the last of the planned Space Shuttle flights," the report stated.
February 2011, it went on, is a better estimate for the final flight.
NASA currently plans to fly four final shuttle missionsbefore mothballing its three space shuttles – Discovery, Atlantis and Endeavour.
In addition to Discovery's April mission, the shuttles are slated to launch on May 18 (Atlantis), July 29 (Endeavour) and Sept. 16 (Discovery). All four missions, as well as a fifth flight that launched earlier this year in February aboard Endeavour, are bound for the International Space Station to deliver vital supplies, science equipment, spare parts or new modules.
NASA officials have said repeatedly that, barring major unexpected delays, the agency should be able to fly the remaining shuttle missions in 2010. In fact, President Barack Obama included $600 million in NASA's 2011 fiscal year budget request to fund shuttle operations through December 2010, in case of those extra months are needed.
"Given the performance of the space shuttle in recent missions and the diligence of the shuttle workforce, NASA has high confidence that, barring any unforeseen technical, weather, or payload delivery issues, the manifest can be safely completed by December 2010," officials with NASA's space operations division in charge of shuttle flights told Space.com in an e-mail.
But NASA should still seek some assurance that funding will be available for shuttle flights should they slip into early 2011, the audit said.
NASA spends about $200 million a month on the space shuttle program and will likely spend about $54 million in overtime pay in an effort to keep stay on track, the new report stated. However, since that is still cheaper than the cost of rescheduling the entire shuttle flight manifest to target a December 2010 retirement, the inspector general's office had no recommendations that the space agency change its current flight schedule.
NASA does, however, need to finalize plans to deal with the post-shuttle era transition and retirement, the report said. By preparing in advance, the space agency will be able to manage the estimated $460 million expected to be required to handle shuttle transition and retirement, it added.
The new report comes on the heels of another audit, submitted Tuesday, that criticized NASA for overspending on conferences in 2009. The shuttle report also comes at a time when NASA's shuttle and human spaceflight program are in flux.
NASA decided to retire its space shuttle fleet in the wake of the tragic loss of the shuttle Columbia and its seven-astronaut crew in 2003. But the agency also initially planned to build new spacecraft and rockets in order to maintain a government-derived U.S. human spaceflight capability.
The space shuttle fleet has been flying since April 1981. Its retirement will end nearly 30 years of shuttle flight.
Several lawmakers are pushing to extend the shuttle program to fill in an expected years-long gap between the shuttle era's end and the availability new American spacecraft and rockets capable of launching astronauts into space.
In February, Obama ordered the cancellation of NASA's Constellation program overseeing the development of the new Orion spacecraft and Ares rockets to replace the shuttle fleet.
Instead, the president proposed NASA embrace commercial spacecraft instead, and set aside $6 billion over the next five years in the agency's budget request to fund those new private space endeavors. That would free NASA to focus on more bold space initiatives, such as manned missions to the moon, asteroids and Mars, supporters have said.
Obama is expected hold a space summit in Florida on April 15 to discuss more details about his new space plan. If all goes according to plan, that summit will occur during the shuttle Discovery's mission to deliver new science gear, supplies and spare parts to the International Space Station.
Top shuttle program engineers and managers will spend Friday discussing Discovery's readiness for that planned 13-day spaceflight. They are expected to spend at least some time reviewing the tests of helium pressurization lines in part of the shuttle's reaction control system.
Earlier this month, engineers found what appeared to be a leak or stuck valve in the helium lines that pressurize the aft-mounted thrusters on Discovery's right rear engine pod. Since then, they performed more tests of other hardware associated with the system, and founded it in good working order.
Shuttle managers will review all those tests Friday and decided if Discovery is indeed ready for launch. If so, the shuttle would be cleared for a planned launch on April 5.
Liftoff is slated for 6:21 a.m. ET on Easter Monday.
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