Report Criticizes Safety of Space Shuttle Boosters : LUSENET : Grassroots Information Coordination Center (GICC) : One Thread

NASA Report Criticizes Safety of Thiokol-Built Space Shuttle Boosters Saturday, March 11, 2000 BY LEE SIEGEL THE SALT LAKE TRIBUNE

Problems with design and manufacture of solid-fuel booster rockets built by Thiokol Propulsion in Utah pose a "major potential risk" and a "high risk" to the space shuttle, says an independent safety report for NASA.

"Any one of these problems could lead to another Challenger accident," said Federation of American Scientists space policy analyst John Pike, who commented on the report Friday.

The report comes more than 14 years after space shuttle Challenger blew up 73 seconds after liftoff from Florida, killing all seven crew members. The disaster was blamed on management failures at NASA and what was then Morton Thiokol.

Thiokol, which builds shuttle boosters at Promontory west of Brigham City, now is a division of Cordant Technologies. The 134-page report by the Space Shuttle Independent Assessment Team (SIAT) of aerospace experts included 81 safety recommendations, only two of which dealt with the Thiokol-built boosters. The text dealing with the boosters was contained in several paragraphs on three pages of the report. "Our folks have not gone through this thoroughly," said Lauren Sides, Cordant's spokeswoman in Salt Lake City. "But of course we will work with NASA to respond to it thoroughly. There is nothing more important to us than safety. . . . Space travel has always been risky. But that doesn't mean we don't work all the time to make it safer and to make our procedures, processes and products safer." Each of the shuttle's twin boosters contains four motor segments that are "poured" or filled with rubbery solid propellant and then connected together. The propellant in each of the eight segments is called a "grain," Pike said.

The National Aeronautics and Space Administration-sponsored safety panel said: "The repeatability and quality of the grains in the Solid Rocket Motor Booster motor segments may not be as thorough as it was in earlier phases of the program. The SIAT is concerned that the quality control for these elements after the motor has been poured is a major potential risk area." Pike's translation: "Each one of those segments is like baking a cake, and no two cakes are exactly alike. There are small flaws, discontinuities and cracks inside that solid propellant. There always are. That means each one of those segments is going to burn slightly different," and the safety panel wants to reduce such variation. If one rocket segment had a large crack in the propellant, "the propellant could burn along the crack and that could lead to a burn-through of the [rocket] casing like you had with Challenger," Pike said.

The safety panel recommended more frequent test-firing of rocket segments "to improve reliability and safety and verify continued grain quality." Challenger exploded because hot gas leaked from a joint separating segments of one of the Thiokol-built boosters. Cold weather had stiffened an O-ring in the joint. NASA had failed to heed warnings from Thiokol workers that the cold weather might cause such a problem.

In the new report, the second Thiokol-related problem involves the nozzle at the bottom of each booster rocket. Each nozzle "is where the hot stuff, the fire, comes out," Pike said. The nozzles swivel to help steer an ascending shuttle.

The report said nozzle components "appear to be located in a very high thermal and mechanical stress zone. The concern for this design is exacerbated because the nozzle and associated joints are reused many times" after rocket casings are jettisoned by shuttles during launch, recovered from the ocean and recycled. Design of the boosters and the inspection and recertification of recycled boosters "should be looked at and analyzed in careful detail," the report said.

Pike said that means "they need to inspect it better after each flight to make sure it is not broken. . . . A failure with the nozzle has the risk of a much more immediate and profound catastrophic failure." For example, "if the nozzle pops off the back, the shuttle would immediately go into a violent turn and break up," he added.. The safety group's third mention of Thiokol's boosters involved the "Thrust Vector Control power unit" near the bottom of each rocket.

Each unit contains toxic, corrosive liquid hydrazine fuel that is burned to drive a turbine. The turbine pressurizes a hydraulic system that makes the nozzles swivel and thus helps steer the shuttle during launch. The panel called it "a high-risk situation" to use hydrazine in such a "highly stressful environment," and said NASA should seriously consider replacing the hydrazine power units with "safer and easier to maintain" electric power units. "Hydrazine is really nasty stuff," Pike said. "There could be a leak and it could catch fire. It has a potential to lead to a catastrophic failure. Or it [the power unit] could fail and you could lose control of the nozzle. The shuttle would have a hard time pointing in the right direction. It could lead to loss of vehicle and loss of crew."

Sides noted that last June, NASA gave Thiokol its highest award for excellence in quality by a contractor. "We're not resting on our laurels, but that tells you we are delivering a good product," she said. When the new safety report was released Thursday, national news reports did not detail specifics about Thiokol, but focused on criticism that shrinking NASA budgets, staffing and oversight of contractors have jeopardized shuttle safety.

-- Martin Thompson (, March 11, 2000


"Oversight of contractors" is due to become one of the biggest issues of the first quarter of this century. It will have a significant impact on this presidential campaign whether kept in the back rooms or emerging into public consciousness.

In the "olden days" it was called pork-barreling. Now, it's "cost effective" and "privatizing". The very people who should prosecute on behalf of the public when mismanagement or fraud occurs are the ones who allocated the contracts. So who now acts on behalf of the people?

-- another government hack (, March 11, 2000.

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