Moonlighting engineers design alternative NASA rocket
Recently, media reports have described a sort of 'shadow army' of engineers who - in their spare time - are designing an alternative to NASA's future Ares rockets.
But who are they? And what exactly is the 'DIRECT' project they are proposing? New Scientist takes a closer look.
What kind of rockets is NASA currently planning?
NASA is developing two different rockets, called the Ares I and the Ares V.
The Ares I is a small rocket that would carry a capsule of astronauts up to low-Earth orbit and to the space station. Known as "the stick", it uses two vertically stacked stages. The first is a solid rocket booster similar to those strapped to the sides of the space shuttle's huge fuel tank. It provides the initial power for lift-off; then the second stage ignites in mid-air to carry the crew into orbit.
The larger Ares V rocket would haul cargo into orbit, including a lunar module that could dock with the astronauts in orbit and shoot them out to the Moon.
What's wrong with those rockets?
NASA has focused on designing the Ares I crew launcher, since the shuttles are set to retire in 2010 and it is aiming to launch their replacement by 2015.
Its design was intended to be cheap and relatively easy, as it was supposed to re-use as much technology from the space shuttle as possible. But that has not been the case, largely because it must carry up a relatively heavy crew capsule, says Roger Launius, head space historian at the National Air and Space Museum in Washington, DC. "The solid rocket booster was not designed to lift this kind of load or to have something stacked on top of it," he told New Scientist.
One major problem is "jack hammer" vibrations caused by irregularities in the way the solid rocket motor burns fuel, though NASA says the problem is fixable. This and other concerns were highlighted in a NASA report made public last week that suggested NASA will probably not meet its own internal goal of launching the rocket in 2013, and may even miss its publicly stated goal of a launch by 2015.
Is anyone thinking of an alternative?
Yes - everyone seems to have an opinion on what NASA should be doing instead. Apollo astronaut Buzz Aldrin, for example, would strap a pod to the side of a shuttle launch system - a plan he calls "Aquila."
But few have pursued their ideas as doggedly as Stephen Metschan, president of TeamVision Corporation - the company that designed the software NASA uses to test its models. For years, he has been developing his own plan for how NASA should get back the Moon.
Relying mostly on forums to generate enthusiasm for their work, Metschan and three others say they have gathered 57 anonymous NASA employees to help them design an alternative.
"I do half of the engineering," Metschan told New Scientist. The others fill in the rest - crunching the numbers and trouble-shooting aspects of the design.
What is the alternative?
Metschan believes that the Ares rocket has strayed from its original Congressional mandate, set in 2005, to recycle as much technology from the shuttle as possible to keep costs low, the space workforce employed, and the window between the shuttle's retirement and the new vehicle as small as possible.
So his plan is called DIRECT, a name meant to emphasise a direct transition from the shuttle to a new system.
The plan uses two identical "Jupiter" rockets - one that would loft only cargo and the other that could carry crew - that are similar in design to a concept developed at NASA's Marshall Space Flight Center after the Challenger shuttle disaster in 1986.
Like the shuttle launcher, each Jupiter rocket would have a liquid fuel tank and two solid rocket boosters. But unlike the shuttle system, Jupiter's liquid fuel tank would have two or three engines at its base and would carry its payload on top rather than on its side - a design that would prevent any insulating foam it might shed from damaging the crew capsule.
Using only one type of rocket, the DIRECT team says, could save NASA $35 billion dollars because it's easier to develop and maintain a single type of vehicle.
What is NASA's reaction?
In 2005, NASA compared 1700 different ideas for the space shuttle's replacement before finally deciding on the Ares rockets. Study leader Doug Stanley said NASA considered designs that, like DIRECT, used one relatively large rocket for all its missions, regardless of the destination.
"We looked at a similar . . . system, and it's true that it would be cheaper for going to the Moon," Stanley told New Scientist. "But it's expensive to use these big rockets to go to the space station."
When NASA scrutinised the DIRECT project itself, however, it was not impressed. In a 2007 report that was released on 3 July, NASA suggested that the DIRECT team's performance numbers for its rocket were overly optimistic. The report also criticised the project's estimated time line (it says it can get the rocket up and running by 2013), its proof of cost and safety and its claims for how much payload the Jupiter rocket could carry.
Will Congress intervene?
"We're not asking you to believe us," Metschan says of the team's figures. "All we're asking is for an independent, apples-to-apples comparison of the two plans." He and his followers are hoping to convince Congress or the next president to task an outside observer like the Government Accountability Office with such an investigation.
But that may be difficult, says Mark Udall, chairman of a congressional subcommittee on space and aeronautics. "We need to . . . actually field a system - not engage in more paper studies and reviews," Udall told New Scientist. "At this point, I am not seeing any significant interest in this [DIRECT] alternative within the halls of Congress."
Whether or not such projects could work or will ever see a dime of funding, their existence points to a larger problem in NASA, says Howard McCurdy of American University in Washington, DC.
When the Apollo Moon programme was being designed in the 1960s, NASA had the money to fund multiple groups that pursued parallel lines of development - and then got to pick the best one. Now the agency is limited by much tighter budgets as a percentage of the overall economy.
Projects like DIRECT are providing an outlet for parallel approaches - forums where frustrated people can sketch out alternative ideas. When NASA pursues a singe line of development, "people on the outside pull out pens and pencils", McCurdy told New Scientist.
http://space.newscientist.com/channe...ceflight_rss20
Originally Posted by The Update Manager
) site and actually explain why everything has to be SO secret. What are they afraid of? That if some of these NASA people that COULD be working on DIRECT, off hours per NASA could be considered unnappoved?
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