NASA is considering retiring a Space Shuttle orbiter in 2007 and beginning modifications to one Shuttle launch pad at the Kennedy Space Center under a plan now being reviewed at NASA headquarters, according to senior agency sources.
Driving the idea of a phased retirement of the space vehicles are two concerns. The first is a desire for finding new sources of funds to pay for advancement of the President's moon-to-Mars plan. And secondly NASA Administrator Michael D. Griffin's fears of a third Shuttle accident.
A source familiar with Griffin's thinking said he is worried that an age-related malfunction would trigger a Shuttle catastrophe. As a result, the space chief is seeking to retire the individual Space Shuttle orbiters as quickly as possible.
No final decision has been made - but discussions continued as Discovery was being prepared for launch.
The idea of phased Shuttle retirement is being promoted both by planners involved in the ongoing Exploration Systems Architecture Study and the Bush White House. Concern is mounting that delays in the operational status of an Earth-orbit version of the Crew Exploration Vehicle (CEV) and Congressional pressure to keep the Shuttles flying until the CEV is available might result in extension of the Shuttle retirement date beyond the fall of 2010.
Anti-Shuttle staffers in the Bush administration want to make certain that the shuttle fleet stops flying in 2010. A phased retirement of the Shuttle vehicles helps make that possibility more likely, according to a NASA source. According to knowledgeable sources, elements in the Bush White House had first sought in 2004 to curtail remaining Shuttle flights to as few as 15 and to reduce the content of the final configuration of the International Space Station.
The idea, while not new, was initially floated to NASA from mid-level staffers while Sean O'Keefe was administrator - as a proposal - one that was immediately rejected out of hand by NASA. Sources say such cuts were never seriously considered in 2004 but the idea was revived this year by mid-level White House staffers when the new NASA Administrator took office in April.
Some at NASA also believe that such actions will allow it to save money which it could then devote toward an accelerated development of the CEV. Plans developed prior to Griffin's arrival at NASA envisioned crewed CEV flights starting in 2014 - 4 years after the Shuttle fleet was due to retire. While he has not specified how much of this gap he plans upon closing, NASA Administrator Griffin has expressed concern that such a gap in independent American access to space for crews is unacceptable.
Some members in the Senate have also expressed concern about this gap. Their solution is to keep the Shuttle fleet around until such time as it is certain that the CEV will actually be ready for duty.
Such intentions were contained within the recently introduced S. 1281, NASA Authorization FY 2006-2010, which calls upon NASA not to retire the Shuttle until such time as the CEV is operational. The bill was introduced by Sen. Kay Bailey Hutchison (R-TX) and was co-sponsored by Sen. Bill Nelson (D-FL).
But senior members of the House of Representatives have also signaled Griffin staffers that they would support an early retirement/ISS cutback plan if it led to acceleration of the CEV. These members are also believed to be concerned about the risks of another shuttle accident.
The differences between the two approaches, if codified into legislation that passes each body, would result in a showdown this fall in a House-Senate conference committee, with the House bill supporting CEV acceleration and the Senate opposed to station cuts. Some in the White House has indicated that it would support the House language.
Discovery is the oldest Shuttle vehicle still in operational status, having entered flight service in 1984. Endeavour is the newest vehicle, constructed to replace the Challenger lost in the 1986 accident. Endeavour made its first space flight in 1992 and is currently undergoing an extensive upgrade to improve its performance and reliability.
If this plan is adopted, the chosen orbiter would only fly three or four additional missions after STS-114 - this despite hundreds of millions of dollars that have been spent on vehicle upgrades for Discovery and the other spacecraft. Under the plan being studied, the retirement of the Discovery or one of the other remaining vehicles would result in its transport to the National Air and Space Museum facility at Dulles International Airport in 2007.
Most of the savings the plan would generate could come from reducing the logistical costs of maintaining a full three Space Shuttle orbiter fleet until 2010.
Under one scenario being studied, a Shuttle orbiter (Discovery) would be retired in 2007. The remaining two Shuttles would fly three times in 2007 and 2008. One of the two remaining Shuttles would then be retired in late 2009 leaving a single Shuttle on flight status in 2010 when it too would be retired.
Another Shuttle manifest being looked at would yield only 12 to 15 total remaining flights including the STS-114 mission. This is in sharp contrast to the 28 to 30 Shuttle flights which NASA had previously identified under Sean O'Keefe as being required to finish the ISS prior to Griffin's appointment as administrator. The obvious conclusion is that a significant amount of already completed ISS hardware would no longer be lofted - at least not by a Space Shuttle. Another flight would presumably be used to mount a Hubble servicing mission - something Griffin has suggested he would support.
A decision to develop a heavy lift unmanned version of the Shuttle has been tentatively made but was not announced to Congressional or industry representatives last week during a series of briefings. Such a new heavy lift vehicle would eventually require modifications to both Launch Complex 39 A and B. Under consideration is a plan to take one pad (probably 39A) out of service soon and begin the modifications.
This Shuttle phase out review may have been a contributing factor in a delay of the announcement of the full 60-day exploration study, which had been targeted for July 18th in Washington. The rollout of the architecture plan is now anticipated no earlier than following the return of the Discovery on July 25th. Among the issues to be addressed by the final plan is how to accelerate the CEV and what sequences the Shuttles will fly from today until 2010.
In a sense, the whole issue of Shuttle retirement and CEV acceleration presents Griffin with a choice that is bound to alienate one or more space constituencies facing the new leader. On one hand, most of the space industry and the Bush White House would look favorably on an accelerated timetable for flying the new CEV - one that is eventually to be constructed in several versions, including Earth orbital vehicles that would visit the ISS and other lunar-capable craft. Contractors involved in various elements of the CEV plan hope to win billions of new contracts for the vehicle and its launching rockets and subsystems.
However, if early retirement of one or more of the fragile, but veteran orbiters means that several elements of the International Space Station now awaiting launch are abandoned, some members of Congress and the international partners are likely to offer resistance to the plan. In addition, those potential users of the ISS who have waited a decade or longer to occupy this facility will now find their long wait to have been a waste of time-and money. Those members of Congress who have supported the ISS since its inception - mainly for the purpose of scientific research - are unlikely to support such a plan.
Yet this may prove to be one of a few steps the Griffin team can take to shave costs from the human spaceflight program to pay for advancing the CEV. Griffin has made it clear he favors such a step. Now having overseen a major - if not convulsive - changeover of experienced managers, ousted in part because the new team believes it has a superior plan than the one it had inherited, it will be up to Griffin to bring this sometimes balky coalition to a consensus that will last.