UPDATE...Likely Fate of Lost Polar Lander Caused By Missing Line of Computer Code

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[Fair use for education and research purpose only] Another Avoidable Mistake For NASA By Kathy Sawyer

Washington Post Staff Writer

Wednesday, March 29, 2000; Page A01

The likely fate of the lost Mars Polar Lander was a 50-mph impact with the planet's frozen surface caused by a missing line of computer code--part of a pattern of avoidable errors that have left the U.S. Mars program a shambles.

Outside investigators announced these conclusions yesterday, as NASA's top scientist confirmed that the agency will cancel plans to launch a robot spacecraft in 2001 on a mission to land on Mars and indefinitely postpone all future launches to Mars, with one exception. A 2001 mission to send a craft to orbit the Red Planet is still on track.

With only its aging Mars Global Surveyor in orbit around Mars, NASA is reassessing its entire approach to the exploration of the planet after losing all four of its spacecraft bound for Mars last year--a package totaling $360 million.

NASA's first priority, officials said, is to comply with the prescriptions of multiple investigations that have revealed serious lapses in the program's management at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., and a long list of shortcomings in areas ranging from systems analysis and testing to staffing and communications.

"They were just young people. We put them in a box there was no way out of," said John Casani of JPL, a veteran of many interplanetary missions who led an investigation into the lander failure. "Management has to take the blame."

The Mars Climate Orbiter was lost because contractor Lockheed Martin's Mars team in Denver forgot to convert from English to metric units, and NASA managers failed to catch the error. Also lost, along with the lander, were two piggybacking microprobes whose fate remains unknown.

The common theme running through all the failures, the investigations have shown, is that NASA's efforts to tighten the budget screws and encourage certain kinds of risk-taking--under a philosophy known as "faster, cheaper, better"--finally went too far. This left the latest Mars projects underfunded, understaffed and overstressed. The JPL team, for example, consisted of just 10 people, each working on a given function in relative isolation and putting in 80-hour weeks.

"We've found the boundary," said NASA's top scientist, Edward Weiler, at a headquarters briefing.

There were scattered signals that something was wrong, investigators say, but the system failed to respond. Both Lockheed Martin and JPL managers may have failed to raise alarms more clearly up the chain of command because of concern that they would lose ground in the competition for tight funding, said Thomas Young, a veteran space company executive and former NASA official who headed the independent Mars review for NASA Administrator Daniel Goldin. "There was clearly some apprehension," he said.

The agency took a team of young, relatively inexperienced people buoyed by the success of the Mars Pathfinder Lander in 1997, greatly reduced their resources and asked them to "do the impossible," Weiler said. The agency will respond fully to all the Young committee recommendations, he said, announcing the beginnings of a restructuring. He added that officials will take a broad, open-minded approach to the full array of options for Mars. "Nothing is off the table."

A comprehensive new plan for Mars exploration will be announced in three or four months, officials said.

The "most probable cause" of the Mars Polar Lander's loss was the generation of "spurious signals" when the lander's legs were deployed during its controlled descent. These signals falsely indicated to the onboard systems that the spacecraft was safely on the surface. This would have prompted the braking thrusters to shut down at an altitude of about 130 feet, investigators found.

The potential for this "spurious signal" problem on the lost lander was uncovered by Lockheed Martin engineers in Denver around early February as they worked on the next lander (the one now canceled). The investigators then helped set up a series of four tests that pointed to this mode of failure as the culprit, Young said.

Although his committee lists various other possible scenarios, he said, if the spacecraft reached this point in its flight, "it's almost certain . . . this is the cause."

Spurious signals of this type are a familiar phenomenon, and routine systems testing should have exposed the potential, he said.

"One line of code" would have fixed the problem, Casani said. Instead, the spacecraft probably ended in a spray of shrapnel when its propellant tanks burst at impact. "There probably was no fire, but it would have been like a land mine going off, one of those Bouncing Betties. You wouldn't want to have been around," he said.

Engineers cannot say for sure whether the spacecraft reached the point where the spurious signal would occur, Young said. This is because project managers, strapped for funds, eliminated telemetry that would have communicated the lander's condition as it negotiated the tricky descent into the Martian atmosphere.

"The team believes that not having this communication system was a major mistake," Young said, because it eliminated the ability of future planners to learn a clear lesson from this costly failure.

) 2000 The Washington Post Company



-- (Dee360Degree@aol.com), March 29, 2000


Rocket Probe Cites Software Error

Story Filed: Thursday, March 30, 2000 9:52 AM EST

LONG BEACH, Calif. (AP) -- A software error in a ground system appears to be what caused this month's failed launch of a Sea Launch rocket, the company said.

The Russian-Ukrainian rocket was carrying a $100 million satellite for London-based ICO Global Communications when it fell into the ocean after liftoff from a floating platform March 12.

The software error would have failed to properly configure the rocket, causing a valve to remain open in the second stage pneumatic system, Sea Launch Co. said in a statement Wednesday.

The pneumatic system is involved in the operation and steering of the engine, and the loss of pressure would have reduced the performance so much that an onboard automatic flight termination system would have been triggered, the company said.

That command was issued about eight minutes after liftoff, Sea Launch said.

The investigation is ongoing but Sea Launch said the progress suggests the system will be ready for another launch by summer.

It was the third launch for the Boeing-led venture. The Zenit-3SL rocket successfully launched a dummy satellite a year ago and a DirecTV satellite was sent in October.

The Sea Launch system uses a converted oceangoing oil rig as a launch pad.

On the Net:

Sea Launch site: http://www.sea-launch.com

ICO Global Communications site: http://www.ico.com

http://library.northernlight.com/EB20000330300000015.html? cb=200&dx=2006&sc=0#doc

-- (Dee360Degree@aol.com), March 30, 2000.

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