Space observers recall the NASA announcement in 1999 that one of its Mars probes had crashed into the planet because workers had mixed up metric and English units of measurement. The story was a real howler, and had elements of truth to it — but it was fundamentally a cover-up and a diversion.
It did turn out that engineers who built the Mars Climate Orbiter had provided a data table in "pound-force" rather than newtons, the metric measure of force (about equivalent to the downward weight of an apple in your hand). NASA flight controllers at the Jet Propulsion Laboratory in Pasadena, Calif., had used the faulty table for their navigation calculations during the long coast from Earth to Mars.
Upon arrival, the probe did not skim the upper atmosphere, as it had been aimed. Misled by the wrong numbers, guidance computers set it on a course that actually hit the atmosphere — where it burned up.
The easy answer — "blame the stupid contractors" — was actually a NASA public-relations gimmick to duck ultimate responsibility for the disaster. In order to promote the image of a faster-better-cheaper space program extolled by the Clinton administration, previously used checks and balances had been canceled. And reportedly, when space navigators intuitively developed a feeling that there was something wrong with the navigational database, they were told to hold the present course until they could prove something was wrong.
By then it was too late. The proper attitude should have been that in case of doubt, steer more safely, and take the corner at Mars farther out. NASA’s mismanagement, not a worker-bee foul-up, doomed that Mars probe...
...But with the Genesis accelerometers, apparently the approved design allowed either direction of installation. From the NASA report, it seems that the accelerometers had to be X-rayed to determine the internal up-down orientation of their sensors, which reportedly were described incorrectly in the technical drawings...
... In September 2003, a quarter-billion-dollar observation satellite was heavily damaged in a hangar when it moved without bolting it to its support frame. A review board recently attributed this to “lack of discipline in following procedures [and] complacent attitudes [and] poorly written or modified procedures.”
In 1998, a LockMart Titan 4 booster carrying a billion-dollar LockMart spy satellite exploded shortly after liftoff from Cape Canaveral, Fla., due to frayed wiring that apparently had not been inspected. The following year, the expensive LockMart Milstar 4 satellite was placed into a useless orbit by a LockMart Titan/Centaur upper stage, because of erroneous calculations fed into the Centaur guidance system. (Explanation: “Engineers were traumatized by the Columbine shootings.")...
Oberg attacks the "better, cheaper, faster" theme of his successor. Presumably he'd advocate a lot more review and redundancy. I suppose the alternative is to do more cheap probes and accept a higher failure level. I suspect there's a reasonable trade-off somewhere in there.
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