Posted 8:59 AM by Blah blah

Space Shuttle Software

More news on the space shuttle Columbia disaster: Shuttle assessment tool was `wrong'. Software couldn't accurately predict damage, investigators find. (Houston Chronicle): " 'Neither NASA nor the board are satisfied with the model. It's essentially an Excel spreadsheet,' not a sophisticated predictive tool, said retired Adm. Harold Gehman, chairman of the Columbia Accident Investigation Board."

That's too bad, because if NASA HAD used or written more accurate software, I'll bet it would have been fantastically high quality. Look at this: They Write the Right Stuff (Fast Company):

"[H]ow much work the [space shuttle] software does is not what makes it remarkable. What makes it remarkable is how well the software works. This software never crashes. It never needs to be re-booted. This software is bug-free. It is perfect, as perfect as human beings have achieved. Consider these stats: the last three versions of the program---each 420,000 lines long---had just one error each. The last 11 versions of this software had a total of 17 errors. Commercial programs of equivalent complexity would have 5,000 errors.

This software is the work of 260 women and men based in an anonymous office building across the street from the Johnson Space Center in Clear Lake, Texas, southeast of Houston. They work for the 'on-board shuttle group,' a branch of Lockheed Martin Corps space mission systems division, and their prowess is world renowned: the shuttle software group is one of just four outfits in the world to win the coveted Level 5 ranking of the federal government's Software Engineering Institute (SEI), a measure of the sophistication and reliability of the way they do their work. In fact, the SEI based it standards in part from watching the on-board shuttle group do its work. [This is part of the SEI's Capability Maturity Model (CMM). See Assessing a Level 5 Organization, about how they judge a group to be among one of the top software groups in the world.]

The group writes software this good because that's how good it has to be. Every time it fires up the shuttle, their software is controlling a $4 billion piece of equipment, the lives of a half-dozen astronauts, and the dreams of the nation. Even the smallest error in space can have enormous consequences: the orbiting space shuttle travels at 17,500 miles per hour; a bug that causes a timing problem of just two-thirds of a second puts the space shuttle three miles off course....Bill Pate, who's worked on the space flight software over the last 22 years, says the group understands the stakes: 'If the software isn't perfect, some of the people we go to meetings with might die.'

In the history of human technology, nothing has become as essential as fast as software."