Scientists had been issuing warnings over funding


Published: Saturday, February 1, 2003 at 3:53 p.m.
Last Modified: Saturday, February 1, 2003 at 12:00 a.m.
WASHINGTON- Scientists have warned Congress for years that the space shuttle program needed more money and newer equipment or else it faced dangerously rising safety risks, and six NASA scientists were fired in March 2001 after issuing such warnings for years.
That might be the root cause of why the space shuttle Columbia exploded Saturday. It was National Aeronautics and Space Administration's oldest shuttle, having first flown in 1981.
But in terms of just what exactly happened to make the ship disintegrate, losing seven lives high above Texas, aerospace experts instantly highlighted two broad possible causes:
  • An explosion on-board because of a defect. Suspicion centers on the highly explosive hydrazine tanks used to power the shuttle's maneuvering and help with electricity for onboard systems or the auxiliary power unit.
  • Alternatively, something may have damaged the delicate space shuttle insulation - ceramic-like tiles and fluffy blankets - that then caused a fatal problem. A hole in the insulation could allow the searing heat of re-entry to burn a hole into the shuttle and explode the hydrazine or on-board fuel cells. Or a hole could allow heat that would then trigger structural damage, such as the breaking off of a wing.
    As the shuttle re-enters Earth's atmosphere, "it's basically a relatively benign thing that's going on . . . The thing is under computer control for the most part," said Seymore Himmel, a former top NASA rocket engineer and a former longtime member of the quasi-independent Aerospace Safety Advisory Panel. "Whatever happened apparently caused an explosion."
    When Columbia launched, television cameras recorded that bits of insulation from its massive and disposable external tank flew and hit the wing. While some experts say this is not unusual and is unlikely to cause serious damage, others say it is a viable possibility that caused the problem.
    "If I was guessing, I would say it's a tile problem," said Norm Carlson, former shuttle operations chief at Kennedy Space Center. "They had some tile that was missing perhaps, and burned through and caused an explosion of a fuel cell tanks or hydrazine tanks."
    If debris hit the right place, one small hole could be fatal, Carlson said. "If it is on the wing, it could burn through and cause structural damage. A wing could come off and whatever, break up. What happens, it literally melts the aluminum."
    "Not that the stuff is heavy and sharp, but once you get up to a certain speed, a piece of Styrofoam traveling at thousands of miles per hour can do a lot of damage," Carlson said.
    Himmel offered another possible cause. "I lean more and more to a structural failure that was structural in origin, or some kind of onboard explosion that leans toward structural explosion."
    For years, a special safety panel set up after the fatal 1967 Apollo 1 fire, had harped on the need for safety upgrades and the lack of money to do them.
    In April 2002, Richard Blomberg, the safety panel's present chairman, told Congress:
    "In all of the years of my involvement, I have never been as concerned for space shuttle safety as I am right now."
    That concern is not for the present flight or the next or perhaps the one after that."
    Since that time, three shuttles flew safely. Columbia was the fourth.
    "One of the roots of my concern is that nobody will know for sure when the safety margin has been eroded too far," Blomberg told Congress "All of my instincts, however, suggest that the current approach is planting the seeds for future danger."
    Last year, the Aerospace Safety Advisory Panel's finding said:
    "The current and proposed budgets are not sufficient to improve or even maintain the safety risk level of operating the Space Shuttle and ISS (International Space Station).
    The panel said: "When risk reduction efforts - such as advanced health monitoring for the Space Shuttle Main Engines, Phase II of the Cockpit Avionics Upgrade, orbiter wire redundancy separation and the orbiter radiator isolation valve - are deferred, astronauts are exposed to higher levels of flight risk for more years than necessary."
    Prior to the present panels finding, six of the safety panel members were summarily dismissed in March 2001 after making such complaints for years.
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