Software Bug Sent Soyuz Off Course

MSNBC ^ | May 5, 2003 | James Oberg

[anymouse]

Astronaut Donald Pettit is carried by stretcher to a helicopter Sunday after he and his two shipmates landed hundreds of miles off course, near the village of Arkalyk, Kazakhstan.

A mysterious software fault in the new guidance computer of the Soyuz TMA-1 spacecraft was the cause of the high-anxiety off-course landing over the weekend, NASA sources tell MSNBC.com .

ONCE IDENTIFIED, the error should be easy to fix in the computer of the Soyuz TMA-2, which is now attached to the International Space Station to provide the new two-man crew with a way to return to Earth.

But until the flaw has been identified and, if it is generic in all models of the spacecraft, repaired, it’s one more worry for the new crew of the space station. They, too, might face a grueling drop back to Earth if they need to evacuate the station.

What happened this time was that the autopilot suddenly announced to the crew that it had forgotten where it was and which way it was headed.

“The auto system switched to backup,” a NASA source told MSNBC.com, “which surprised them”.

U.S. astronaut Kenneth Bowersox, one of the three men aboard the Soyuz, was even more dramatic in an interview given on his way back to Moscow.

“The first thing we saw was signs on our displays that the entry was going to be off nominal,” Bowersox said. “And when we saw those signs our eyes got very wide.”

Historically, this is a very rare type of failure. It occurred several times between 1967 and 1975, but never afterwards. Thus, suspicion immediately focused on this new Soyuz’s “improved” guidance computer.

“Ken suspects a software problem”, a NASA source told MSNBC.com.

Software problems in the Soyuz guidance computer aren’t just a matter of landing randomly back on Earth; they are potentially fatal. In 1988, a confused guidance computer nearly jettisoned the Soyuz T-6’s rocket engine section while the crew was still in orbit, a malfunction that would have doomed the men to a slow death by suffocation. Only the alertness of one of the pilots detected and aborted the insane command. This time, since Budarin, Bowersox and Pettit knew that their backup descent profile was safe — if rougher — they kept their hands off the manual controls. “They didn’t do anything,” MSNBC.com was told. ”[They] just let the auto system control.”

James Oberg, space analyst for NBC News, spent 22 years at the Johnson Space Center as a Mission Control operator and an orbital designer.

[anymouse]

The rest of the story, about the wayward Soyuz capsule.

[anymouse]

Space ping

[Noslrac]

I think i'd rather fly on the shuttle any day.

[Nick Danger]

[anymouse]

Technically the Russian Soyuz is statistically safer than the US shuttle.

[Brad C.]

Wait, don't tell me some engineer mixed his measurement systems together again.

[meenie]

Technically, they are both dangerous and both statistically bound to have unforeseen problems with computer glitches. Kelly's law of probability guarantees this. If something can go wrong, it probably will.

[Ursus arctos horribilis]

I once size a compressor and goofed badly over a mistake that was dumb, dumb. Use PSIG (pound square inch gauge) when it should have been PSIA (pound square inch absolute) for ratings &c.

Young and dumb didn't cut it, it was stupid. After that I always found another way to screw up.

[El Gato]

They are very lucky to be alive. They pulled around 9 Gs, when the profile was only 4 1/2 or so. A little steeper approach and they'd be dead. I wonder if they blacked out? I would expect that they did, since 9 G is about the limit for a fighter pilot, with a G suit and utlizing straining techniques. They probably had no G suits, and had been in zero G for a long time, which would reduce their G tolerance considerably.

[Centurion2000]

A mysterious software fault in the new guidance computer of the Soyuz TMA-1 spacecraft was the cause of the high-anxiety off-course landing over the weekend, NASA sources tell MSNBC.com

Thank you Microsoft for allowing the piss poor software design philosophy / controls in programs that SHOULD be beta or alpha copies get exported to the rest of the world as finished product.

Remember when programs worked perfectly the first time you bought/wrote them ?

[El Gato]

Naturally the Russian technocrats tried to blame it on the Americans. I guess managers are managers no matter were they are located. How do you say cover your a$$ in Russian?

There was also the real possibility of crew error, and on Sunday, the head of the corporation that builds and operates the Soyuz spacecraft, Yuriy Semyonov, suggested that “one of the Americans” had pushed the backup-mode activation button. Bowersox was the only American who had any active role in the descent (it was astronaut Donald Pettit’s job to follow the checklists), and he denied touching the button — which, he joked, was being guarded carefully by Russian cosmonaut Nikolai Budarin. “We don’t think we did anything to cause that to happen,” he later said to a NASA press official.

[Russian Sage]

It's a good thing that software bugs are so rare.

[El Gato]

The three men, who knew they were far off course, were able to open the hatch themselves and get out; it’s a much easier drop to the ground when the capsule is on its side. They then waited two hours to be spotted by a search plane, and several hours more for the arrival of the first helicopter.

That part could have been worse, they could have been bobbing around on the briney for those several hours + 2. I wonder what the biggest "miss distance" of the Mercury/Gemini/Apollo programs were. I don't think Apollo ever missed by much, but I can remember how exciting it was the first time one of them (Gemini?) came down close enough to the recovery ships that those on the ships could see the main chute once it opened. Even showeded on TV, IIRC.

[upchuck]

Thank you Microsoft for allowing the piss poor software design philosophy / controls in programs that SHOULD be beta or alpha copies get exported to the rest of the world as finished product.

Let me guess. The Soyuz guidance systen is a hacked version of "Flight Simulator?"

[greasepaint]

The Russians were smart enough to build some reserve-safety
into their decent vehicle.
Nasa, for whatever reason, didn't.
The space shuttle is a deathtrap.

[bvw]

Cheap is good and safe. The trouble with money is the porkers run at it hard and make things that don't work and are risky. Fear, not confidence, is better for asking for more money. When a pensionaire's money is the motivator, the pride of a good job done well gets the red stapler guy's cubical way back in the basement storage area.

Cheap is safe.

[NCC-1701]

MA-8, also known as "Aurora 7", flown by Scott Carpenter holds the American record for the most distance overshot for lading. He used up almost all of his reaction control fuel long before retro fire. He therefore had to nudge his Mercury spacecraft into an attitude to fire the retros. His miss distance was about 200 miles, similar to Soyuz TMA-1. He had to climb out the nose of Aurora 7 and wait several hours for the Navy to get to him. All the rest of the splashdowns were well within the recovery zone. A note of history here, the Russians have landed all but one spacecraft on land. The lone exception was an early Soyuz which splashed down in a frozen lake. It took recovery forces a day or two to get the crew and spacecraft out and back on dry land.