WASHINGTON — NASA Administrator Charles Bolden said the U.S. space agency intends to build a heavy-lift rocket that meets the manifold requirements Congress set for the new booster, but that the heavily shuttle-derived design it sent lawmakers Jan. 10 could change if internal studies and industry input yield a more affordable approach.

NASA’s baseline heavy-lift design, outlined in a congressionally mandated report delivered Jan. 10 to Capitol Hill, calls for a liquid hydrogen-fueled rocket that would use the space shuttle’s RS-25 main engines, giant external fuel tank and five-segment versions of the solid-rocket boosters the shuttle jettisons on its way to orbit.

However, to the consternation of some key lawmakers, NASA said  neither the rocket nor the Orion-based crew capsule it would launch could be completed within the cost and schedule Congress outlined for the project in the NASA Authorization Act of 2010 late last year.

“We presented baseline reference vehicles and ideally if we can find a way to make it happen, the baseline reference vehicles will be the vehicles of the future,” Bolden said in a Jan. 12 interview. “If we can’t then we will come back with alternatives that we will have developed through coordination with industry and the Congress. So my hope is we’ll make this thing firm, but I can’t say that right now.”

Congress directed NASA last fall to get started this year on a multipurpose crew exploration vehicle and a heavy-lift rocket initially capable of hauling 70 to 100 metric tons to orbit. That guidance was included in the NASA Authorization Act that U.S. President Barack Obama signed into law in October. The law gave NASA 90 days from enactment to submit a report outlining reference designs for the rocket and crew vehicle.

NASA’s preliminary conclusion in the Jan. 10 report was that the best approach for meeting the heavy-lift requirements spelled out in the law would be to build a rocket that incorporates the space shuttle’s nearly 8.4-meter-diameter external tank, five RS-25 space shuttle main engines, and a pair of five-segment solid-rocket boosters similar to those NASA and industry have been developing for the Ares family of launchers Obama targeted for termination in the 2011 budget blueprint he sent lawmakers last February. The design ultimately would evolve to incorporate expendable versions of the reusable RS-25 engines and a J-2X-based upper stage, which Canoga Park, Calif.-based Pratt & Whitney Rocketdyne has been developing for the Ares 1 and Ares 5 family of rockets. The report also said NASA would meet the authorization act’s call for a multipurpose crew vehicle by continuing development of a deep space version of the Orion Crew Exploration Vehicle the agency began in 2006 under the Constellation program.

The authorization act gives NASA until 2016 to field the heavy-lift rocket and crew vehicle, and authorizes Congress to spend more than $10 billion on the two projects over the next three years.

While NASA’s Jan. 10 interim report states that “neither Reference Vehicle Design currently fits the projected budget profiles nor schedule goals outlined” in the law, Bolden told Space News the agency did not tell lawmakers NASA could not produce a heavy-lift launcher and space capsule within cost and schedule constraints specified by Congress.

“We are a can-do agency,” he said in a Jan. 12 interview. “So we did not say we could not do what [Congress] told us to do in the authorization act.”

Bolden said he told Congress NASA is “doing everything we can to carry out a robust exploration program. That’s what the president wants, that’s what I want.”

NASA Deputy Administrator Lori Garver, in a separate interview Jan. 11, said  it will be difficult for NASA to settle on a design until the agency has a better sense of the funding congressional appropriators will provide for the effort in 2011 and 2012.

“You clearly need that before you … decide on the best approach going forward,” Garver said.

The Senate Commerce Committee, which took the lead in drafting the 2010 NASA Authorization Act, issued a Jan. 12 statement highlighting NASA’s conclusion that it cannot build a capsule or heavy-lift rocket based on the cost and schedule outlined by Congress.

“We appreciate NASA’s report and look forward to the additional material that was required but not submitted,” four top committee members, including Sens. Bill Nelson (D-Fla.) and Kay Bailey Hutchison (R-Texas), said in  the statement. “In the meantime, the production of a heavy-lift rocket and capsule is not optional. It’s the law. NASA must use its decades of space know-how and billions of dollars in previous investments to come up with a concept that works. We believe it can be done affordably and efficiently — and, it must be a priority.”

In a separate Jan. 13 letter to Bolden, Nelson and Hutchison challenge NASA’s conclusion that a heavy-lift rocket cannot be built within the cost and schedule parameters Congress outlined.

“If the law directed NASA to start with an entirely new development without use of existing contracts, technologies, and infrastructure, we can see where affordability may come into question, but this conclusion suggests a misunderstanding of Congressional intent,” Nelson and Hutchison wrote. “The law directs NASA to build on past investments in human space flight by leveraging existing knowledge and assets from the Space Shuttle and Constellation Programs.”

The lawmakers continued: “We specifically rejected the notion of relying on major new developments in launch vehicle design — the schedule and cost risks associated with such an approach have been the Achilles’ heel of too many prior efforts to develop new launch systems at too great a cost.”

NASA’s associate administrator for exploration systems, Doug Cooke, said that while the cost models NASA used for the heavy-lift and crew capsule design outlined in the Jan. 10 report failed to produce estimates that fit within the scope of the new law, the agency continues to look for savings opportunities.

“With traditional approaches we can’t get there, so that’s why we’re looking at all these affordability approaches,” Cooke told Space News following a Jan. 11 presentation to the NASA Advisory Council’s exploration subcommittee here.  

Cooke said the leading heavy-lift rocket designs NASA examined — including a “clean-sheet” liquid oxygen/kerosene design and a version similar to the Ares 5 vehicle — had comparable development and life-cycle costs. An advantage of the design NASA sent Congress, he said, is the ability to use existing space shuttle and Ares rocket assets before upgrading to more advanced capabilities.

“If we have that ability, we can actually phase follow-on upgrades to the main engine that would be needed for producibility and potentially future competitions for boosters that could be an upgrade to current designs,” he said. “So that really was the reason we went that direction.”

This design would ultimately evolve to provide a rocket capable of delivering 130 metric tons using a J-2X-powered upper stage.

Cooke said NASA expects to deliver a final report to Congress in the spring, pending the results from a slew of heavy-lift study contracts awarded to 13 U.S. companies in November.

He said the studies, due in May, should help NASA validate its heavy-lift reference design and decide whether another approach is worth considering. “If it’s marginally different, and we lost a benefit, even if it’s not cost, I’m not sure we would change it,” Cooke said. “But if there were a dramatic difference we should obviously consider it.”

Constellation continues

Meanwhile, NASA Inspector General Paul Martin waded into the debate Jan. 13, urging Congress to “take immediate action” to permit NASA to reduce or cease funding parts of the Constellation program NASA and Congress “have agreed not to build.”

While the 2010 NASA Authorization Act directs NASA to build a new heavy-lift rocket and multipurpose crew vehicle to replace the rockets and capsules being built under Constellation, NASA cannot cancel Constellation contracts and establish new projects in their place until Congress enacts appropriations legislation lifting a 2010 ban on killing the 5-year-old program.

“Without congressional intervention, by the end of February 2011, NASA anticipates spending $215 million on Constellation projects that, absent the restrictive appropriations language, it would have considered canceling or significantly scaling back,” Martin wrote in a Jan. 13 letter to NASA’s congressional oversight committees.

Martin said that figure could grow to more than $575 million if the Constellation restrictions remain in place through September, when the U.S. government’s 2011 budget year ends.

NASA, like the rest of the federal government, has been operating since Oct. 1 under a so-called continuing resolution, or CR, Congress passed in lieu of enacting a new budget for 2011. Under the CR, NASA is funded at the same $18.7 billion level Congress approved for 2010.

Rep. Ralph Hall (R-Texas), the chairman of the newly renamed House Science, Space and Technology Committee, said he agreed with the NASA inspector general that congressional appropriators need to address the Constellation restrictions swiftly “in order to avoid wasteful spending.”

“NASA should be taking steps to prioritize spending on projects that are likely to have applicability in a future heavy lift vehicle, in an effort to maintain production lines and reduce inefficient use of taxpayer funds,” Hall said in a Jan. 13 statement.

Cooke said despite the legal mandate to continue funding Constellation projects, operating at 2010 spending levels nevertheless has forced the agency to scale back work on the program.

“We’re trying to do the best we can at making our work meaningful for where we think things are headed,” Cooke said. “We don’t like wasting money and so we’re doing everything we can to make it count.”