A Programing Error Blasted 19 Russian Satellites Back Towards Earth (arstechnica.com)

An anonymous reader quotes Ars Technica's report on Russia's failed attempt to launch 19 satellites into orbit on Tuesday: Instead of boosting its payload, the Soyuz 2.1b rocket's Fregat upper stage fired in the wrong direction, sending the satellites on a suborbital trajectory instead, burning them up in Earth's atmosphere... According to normally reliable Russian Space Web, a programming error caused the Fregat upper stage, which is the spacecraft on top of the rocket that deploys satellites, to be unable to orient itself. Specifically, the site reports, the Fregat's flight control system did not have the correct settings for a mission launching from the country's new Vostochny cosmodrome. It evidently was still programmed for Baikonur, or one of Russia's other spaceports capable of launching the workhorse Soyuz vehicle. Essentially, then, after the Fregat vehicle separated from the Soyuz rocket, it was unable to find its correct orientation. Therefore, when the Fregat first fired its engines to boost the satellites into orbit, it was still trying to correct this orientation -- and was in fact aimed downward toward Earth. Though the Fregat space tug has been in operation since the 1990s, this is its fourth failure -- all of which have happened within the last 8 years.

"In each of the cases, the satellite did not reach its desired orbit," reports Ars Technica, adding "As the country's heritage rockets and upper stages continue to age, the concern is that the failure rate will increase."

Comments

C'mon guys, this isn't rocket science.

[hey!]

Actually this is fairly typical of rocket science, at least as I understand it. Spacecraft are complex systems where they only way to avoid catastrophe is to get an almost incomprehensible number of easy-to-overlook details right. Maybe it's the unit conversions, or the temperature rating of the booster O-rings, or the combustibility of cabin materials in a pure oxygen atmosphere.

Maybe this is not what we programmers would technically call a "programming error", although other people might characterize it that way, but it comes from a practice that is all-too-familiar: cutting values from one source and pasting them into another, something you do for convenience but which opens the door for details to be wrong in an unexpected way.