Reply to post: Re: Better yet,

Lonely bloke in chem suit fuels Mars orbiter


Re: Better yet,

NASA were the ones who stoofed into the surface of Mars when they got their units mixed up.

You say NASA, but the root cause was that NASA's contractor who incorrectly wrote the software. NASA specified metric to Lockheed Martin for the Mars Climate Orbiter; NASA wrote navigational software expecting metric; Lockheed signed the contract and accepted the software interface specification calling for metric. Lockheed then delivered results in US customary units.

Some blame does fall on NASA in that two of its navigators were reporting that the MCO a bit off course earlier in the flight after trajectory correction maneuvers (TCMs) 2 and 3. After TCM-4, there was a week's period where calculations were clearly showing MCO was coming in below the target 226km altitude, with estimates of 150 to 170km - which is a huge error by NASA's navigational standards. 24 hours before orbital insertion, updated calculations were showing a pass as low as 110km, and the MCO could only handle 80km at the worst. The flight plan offered a chance for TCM-5, but the MCO team held a meeting and decided the situation wasn't bad enough for that.

Then MCO buzzed Mars at 57km, supplementing an out-of-the-envelope aerobraking maneuver with an unscheduled lithobraking maneuver. The root of that error is Lockheed, though, not NASA.

Have they checked that all the bolts are present and tight?

Heh, those stands do bring to mind the NOAA mess.

But, sidebar question: two of the early comments on this thread regard early 2000s goofs by Lockheed Martin Aerospace division, it's unplanned shock testing of a NOAA weather satellite and the incineration of the Mars Climate Orbiter. What do either of those have to do with a spacecraft built by Thales Alenia and launched on a Rooskie rocket?

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