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Switch goof in Genesis is detailed

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"This side up" should have been the label on switches inside the Genesis spacecraft.

That's the gist of what went wrong with the Genesis probe, which slammed into the mud of Dugway Proving Ground Sept. 8. After three years and 1.86 million miles in space, the craft with its precious cargo of solar wind samples failed when it was on the brink of success.

Instead of a midair catch by a helicopter equipped with special capture gear, the probe crashed on the desert floor. The impact ripped open the spacecraft and the science capsule inside — most of the 3,000 glassy collector plates were broken, though some survived intact.

Scientists are hopeful they can retrieve useful data from the broken plates, so the $264 million project may not be a loss.

On Thursday, NASA's Genesis Mishap Investigation Board issued a preliminary report concluding "the likely cause was a design error that involves the orientation of gravity-switch devices." The report says the switches may not be the only flaw, and study of the debris continues near Denver.

But the crash was blamed on gravity switches, said Michael G. Ryschkewitsch, chairman of the investigation board, who spoke with the Deseret Morning News Monday from NASA's Goddard Space Flight Center in Greenbelt, Md. The switches "sense the deceleration when the capsule enters the upper atmosphere."

"And in the case of Genesis, the gravity switches were installed by design in a position reversed from the position they should have been."

The circuit card with the gravity switches was designed and installed by contractor Lockheed Martin in Denver, Ryschkewitsch said. However, he added, the project was part of a NASA program run by the Jet Propulsion Laboratory in Pasadena, Calif., and JPL was responsible for a number of reviews before launch.

The Deseret Morning News made five attempts to reach officials at Lockheed Martin on Monday but was unsuccessful.

An important question is why NASA's tests and reviews did not catch the flaw, said Ryschkewitsch.

When the spacecraft hit Earth's atmosphere on its return trip, it was traveling about 25,000 miles per hour, and air drag caused it to decelerate. At that point, the gravity switches — each described as a small plunger on a spring — were supposed to cause the drogue parachute to deploy.

Deceleration should have pushed the plunger onto an electrical contact, the way a person feels the seat belt pressing when a car suddenly slows. On Genesis, when deceleration dropped further, the spring was to push the plunger back from the contact.

"That triggers first the drogue deployment and a little while later, the parafoil deployment," Ryschkewitsch said. Those are the two parachutes that were supposed to allow Genesis to drift slowly toward ground.

Because the gravity switches were facing the wrong way, deceleration would not have pushed the plunger onto the contact. The parachutes never deployed.

The $183 million Stardust space probe, which has similar design features, may not carry the same flaw. Having caught samples from a distant comet, Stardust is headed toward a January 2006 parachute landing at Dugway.

"What I've been told is the Jet Propulsion Laboratory and the Lockheed Martin folks working with Stardust have looked at the similar switches and they believe they were installed in the proper orientation on Stardust," Ryschkewitsch said.

That doesn't mean another flaw could not be duplicated, however — Stardust has "very similar hardware." But Ryschkewitsch said he is not prepared to draw final conclusions until the Genesis review is finished.

Orlando Figueroa, deputy associate administrator for programs in NASA's Science Mission Directorate in Washington, D.C., said a more complete Genesis report may be released in November.

"We hope to walk through anything else that may be wrong with the Genesis as well as the root causes," he said. The root cause is "how did we miss it?"

With Stardust, "the preliminary indication is that the drawing and the installation of the (gravity switch) devices is correct."

Why would the switches be wrong on Genesis but right on Stardust?

"These are very complex systems, and how they were assembled are part of the questions we are asking ourselves," Figueroa replied.

E-mail: bau@desnews.com