Down-to-Earth Woes Ground NASA’s Futuristic Spaceship

NASA has spent four years and about $1 billion developing a replacement for the space shuttle, with nothing to show for it but a half-built prototype sitting in a Palmdale hangar.

The X-33 spacecraft was supposed to make its first test flight 18 months ago, rocketing 450 miles in less than 15 minutes from California’s Edwards Air Force Base to a Utah landing strip. But engineering problems have beset the project almost from the start, leading some experts to doubt it will ever fly.

The most serious problem arose last November, when one of the spacecraft’s hydrogen fuel tanks ruptured during a test. Now NASA has run out of money for the project, and contractor Lockheed Martin has spent more than the $220 million it committed to develop the X-33.

In the wake of last year’s back-to-back Mars mission failures and repeated delays in constructing the space station, a high-profile success would help rehabilitate NASA’s tarnished reputation. The X-33 could have produced that success, but for almost a year the space agency has kept the project out of the limelight.

NASA officials characterize problems with the spacecraft as a temporary setback.

“We think that we’re probably looking at about a two-year delay from this year to 2002,” said program manager Gene Austin.

Others in the space industry are skeptical.

“I think the X-33 will never fly, and I’m not alone in that opinion,” said Tim Kyger, a former congressional staffer who works for Universal Space Network, a company that provides satellite tracking services.

Craft Was to Carry U.S. Dreams Aloft

The X-33 was supposed to be a big improvement over the space shuttle. It was envisioned as a reliable, reusable spacecraft that could cut launch costs from about $10,000 per pound today to $1,000 or less per pound in 2006 or 2007. Cheaper launches would open the way for a range of commercial uses that are unprofitable today, from tourism to semiconductor manufacturing in space.

In the beginning, the X-33 was a high-profile project. Vice President Al Gore unveiled it in 1996 at a ceremony at NASA’s Jet Propulsion Laboratory in Pasadena.

“This is the craft that can carry America’s dreams aloft and launch our nation into a sparkling new century,” Gore said as he and NASA administrator Dan Goldin lifted a box to reveal a model of the wedge-shaped spaceship.

Critics said the craft’s futuristic design is at the heart of the problem. NASA could have chosen to build a space shuttle replacement by developing proven technologies, but instead took the high-risk path of trying to build something almost entirely new.

When NASA first asked for proposals to build a replacement for the space shuttle, three aerospace companies applied to work with the space agency on the project.

“We evaluated all three proposals and Lockheed Martin was the clear winner,” Austin said.

Critics wonder how that could be. Even four years ago, they said, it was apparent that the technological hurdles facing Lockheed Martin’s Buck Rogers design would be difficult to clear.

The design required development of linear aerospike rocket engines, which have never been used in flight. It required the development of a wingless “lifting body” airframe that could keep the vehicle flying smoothly during launch and as it returned to Earth.

‘High-Risk, High-Payoff Approach’

Most challenging of all, it required oddly shaped composite fuel tanks that could withstand the pressures of a space launch while filled with pressurized liquid hydrogen at a temperature of 423 degrees below zero Fahrenheit.

“NASA did not take the low-risk path. They chose the high-risk, high-payoff approach,” Dave Urie, the engineer who designed the spacecraft, said in a 1997 speech.

The Skunk Works, Lockheed Martin’s renowned Palmdale design plant, went to work on the challenges. Over the last 50 years, Skunk Works engineers have produced some of aeronautical engineering’s most amazing creations, including the first production jet aircraft, the U-2 spy plane and the F-117A Stealth fighter.

But even for the Skunk Works, the X-33 was a bear.

Delays and cost overruns are common in the aerospace industry, but the financial structure of the X-33 project made it especially vulnerable to problems. NASA had agreed to spend $941 million on the project through 1999, with payments to Lockheed Martin in installments as the contractor met certain milestones. For its part, Lockheed Martin would put $220 million into the project.

The agreement required that if additional costs arose or technical obstacles kept Lockheed Martin from reaching a milestone on time, the contractor would have to come up with the additional money to keep the project afloat.

And things did keep popping up. Building the hydrogen fuel tanks took longer than expected. Late delivery of the linear aerospike rocket engine, being built by Boeing, pushed back the date of the first planned test flight and added $36 million in costs.

Then, in late 1998, technicians noticed bubbles and cracks in the skin of one of the two liquid hydrogen tanks as it was being cured in a giant oven. Replacing the defective tank led to another delay and a cost overrun of almost $5 million.

With the engine and the hydrogen tanks continuing to pose the most difficult challenges, engineers kept making gradual progress on the X-33 right up until Nov. 3, 1999, at 6:45 p.m.

That afternoon, engineers at NASA’s Marshall Space Flight Center in Huntsville, Ala., had tested one of the troublesome hydrogen tanks. The test involved filling the tank with liquid hydrogen while it was under the same stresses it would experience during flight.

The test went fine. But after they drained the freezing cold liquid hydrogen, workers discovered that the tank was coming apart.

Within two weeks, NASA had appointed an investigative team. They promised a complete report on the tank failure by the end of the year, but nothing came out, and very little was said about the X-33 until NASA finally released the report Aug. 10. It concluded that a phenomenon known as “cryopumping” had caused the tank to fail.

Lockheed Martin engineers had put a hollow “honeycomb” layer inside the tank wall, and microscopic cracking during the load test had allowed air in. Because of the extreme cold of the liquid hydrogen inside the tank, that air froze, going from gas to solid.

Once the test was over and the liquid hydrogen drained, the tank warmed up again. The frozen air returned to gaseous form and expanded, but it couldn’t get out as easily as it got in because the cracks in the tank wall’s outer layer had closed.

The air inflated the honeycomb space inside the tank wall like a balloon. The graphite layers peeled apart.

Urie, the original designer of the X-33, had advocated simpler composite tanks. The honeycomb structure so compromised his original design, he says now, that it had little chance of succeeding.

“It was in my view a mistake to abandon well-known and well-tested technology,” said Urie, who retired from Lockheed Martin in 1996, in part because he was disgusted at changes in his design.

“I guess they got what they deserved,” he said.

Now the space agency and Lockheed Martin are embroiled in what Kyger calls a “Mexican standoff” over how to continue the project and who will pay.

Meanwhile, the space agency has requested another $4.5 billion over the next five years for the Space Launch Initiative, a program that would step back and explore a number of other reusable launch vehicle possibilities besides the X-33. Some of that money could be used to continue the X-33 project, but most would go to other technologies.

It appears that Congress will approve the money, to the exasperation of the space launch industry.

Entrepreneurs who have been trying to develop private, low-cost space vehicles said NASA’s promise to build the X-33 has made it impossible for them to obtain financing. They say the Space Launch Initiative will just make it worse by giving NASA complete control over developing new technologies.

Aerospace consultant Charles Lurio, one of those who believes that private industry could do it faster, better and cheaper than NASA, called the Space Launch Initiative “this thing that Joe Stalin would admire.”

The easiest fix for the problem might be to switch from risky composites to tried-and-true aluminum tanks. NASA project manager Austin said recently that Lockheed Martin engineers have come up with an ingenious aluminum-tank design that would decrease the weight of the X-33.

That may be good enough for a test flight, Urie said, but he doubts that it will be good enough for the craft to make it into orbit.

NASA will make a final decision by the end of the year on whether to continue with the composite liquid hydrogen tanks or go with aluminum, Austin said.

Kyger is among those who wonder if the program will even be alive by then.

“Not a thing will be said about this by NASA until after the election,” he predicted.

And then?

“It will be quietly put to sleep.”

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On the Net: Lockheed Martin VentureStar page: www.venturestar.com

NASA Watch: www.nasawatch.com

NASA X-33 page: www.x33.msfc.nasa.gov