STS-121 Might Not Launch Until Late '06

Aero-News Analysis by Senior Correspondent Kevin R.C. O'Brien

The hits just keep on coming for the Space Shuttle and NASA's embattled administrators. According to a report by MSNBC's space reporter James Oberg, problems with center fuel tanks make any launch unlikely before early 2007.

While the destruction at NASA's tank-building facility in New Orleans, and damage to a completed fuel tank there, is a problem, a more serious and intractable difficulty is the shedding of insulation from the center fuel tank.

Oberg obtained an internal NASA memo detailing the storm damage, the problems with central tanks, and their likely consequences for the launch schedule.

The Damaged Facility

The Michoud, Louisiana facility where Shuttle main tanks are made is operated by giant prime contractor Lockheed Martin, and was hard hit by the storm. The facility itself was damaged, a completed main tank (that was destined, according to NASA's original Return To Flight plans, to be mated with Atlantis... and launched in the next couple of weeks) was damaged as well.

The real problem is that many of the workers' homes suffered terribly, as did New Orleans area infrastructure. NASA is looking at months before vital highway bridges are repaired (although the speed with which contracts have been let is encouraging). Many of the key workers in Michoud who didn't lose their homes have to cross those bridges to get to work.

Key data is on computer systems that survived intact but are without power, and for the time being NASA has no access to the site to recover the data or computers. That will change when the security and health situation permits, if authorities don't escort NASA experts in sooner.

The port facility from which the tank travels to Canaveral took a walloping, also, and is plugged with debris. But the real gating factor in restoring Michoud to operation will probably the lack of decent places for the workers to live. Over half of them are displaced, some near other NASA facilities.

NASA is exploring options for making and preparing the tanks elsewhere. A very large clean room is required, but this could be done in the gigantic Vehicle Assembly Building, by setting up overpressured and sealed tents inside.

The facility from which solid rocket boosters are shipped is in Mississippi and also was hit by Katrina, but it was much less heavily damaged than the Michoud facility. However, it shipped its boosters by rail from New Orleans, and the rail terminal and bridges are in poor shape.

If the Michoud facility was the only problem, NASA would be able to hit its revised launch date of May 2006. (Pushed back from March, which was where the initial assessment of the insulation problem from Discovery's last flight slid it to from this month). But the other damage in New Orleans complicates getting even a perfect product from Michoud to the Gulf -- and thence around Florida to Cape Canaveral. And if that's not bad enough, the definition of what a "perfect product" is...isn't exactly final.

The Tank Problem

The problem with delivering the tanks is only one worry for NASA managers. The deeper problem is that they still aren't sure how to make and insulate safe tanks.

NASA instrumented the tank used on STS-114 extensively, expecting, among other things, to validate the Computational Fluid Dynamics models they used to design the insulation. Except: the data didn't match the theory. Instead of validating the model, they invalidated it. Not only that, but the aerodynamic pressures around critical components of the tank are not only not what the model expected, they're not remotely steady. This means that the aerodynamic assumptions that make the whole idea of using a CFD model for this part of the design are out the window -- and leaves the rocket scientists scratching their heads.

They will, of course, continue to reduce the data, and anything may come of it, including fundamental new theoretical developments extending the reach of CFD or improving our ability to model transonic and supersonic flows in complex systems. But from NASA bosses' viewpoint, this may come, but it cannot come soon enough to prevent a problem.

While the results from instrumenting the tank are very frustrating to NASA and space watchers right now, having a known aerodynamic problem that's incredibly hard to deal with sure beats having an unknown, and potentially devastating, aerodynamic problem.

Why The Simple Solution -- Isn't

NASA continues to dismiss the "simple solution," of returning to the earlier, safe, insulation that was used through 2002. That insulation contains internationally banned chlorofluorocarbons (CFCs) which contribute to ozone layer depletion. This sounds like a simple solution, but it's apparently not legal.

Then, there's the simple fact that the "safe" insulation, like the "unsafe" insulation, used to shed flakes on every flight. No one thought that it was a serious hazard until the loss of the orbiter Columbia in 2003 grabbed everybody's attention. It is quite possible that the

And if the US backs off on CFC reduction, it will have great problems getting China and India -- the two main producers of CFC pollution now -- to cut back on their use of these chemicals.

The Consequences

These new delays -- and new expenses -- put the shuttle program itself at risk. NASA leaders envisioned ending the shuttle program in 2010, already. (Contractors previously believed that they can keep the shuttles flying till 2030 or so). The new plan envisioned only 15 to 28 more shuttle flights before retirement of the system -- and that plan is already OBE (Overcome By Events).

There is no practical way now to deliver large items to the International Space Station. This means that the station will remain in caretaker mode for the foreseeable future, with construction suspended.

Look for a lot of ideas to be kicked around over the next few weeks and months. There is still a possibility some individual or team can come up with a radical new solution to the insulation problem. There's also a possibility, although a much lesser one, that NASA may choose to accept certain risks it's been trying to design out of a complex, risky system.

But for now, it looks like manned spaceflight in 2005 and 2006 will remain the province of Russia, China, and private operators in suborbital flight. If you hang your hard hat in NASA's manned spaceflight program, this is nothing short of a calamity. If you hang your hat in, say, Mojave Spaceport, this is an opportunity.

FMI: www.nasa.gov