Classified Satellite Failure Led To Latest SBIRS Delay

The loss of a classified satellite after only 7 seconds on orbit prompted the review of software and processors that has caused the most recent delay and a potential $1 billion overrun in Lockheed Martin's Space-Based Infrared System (SBIRS), says Gary Payton, deputy under secretary of the Air Force for space programs.

The classified satellite went into a "safe hold," mode, which is initiated when a major anomaly disrupts its operation, and the failure of the safe-hold software made it impossible for ground-control to recover the spacecraft. Payton refers to it as a useless "ice cube."

The safe-hold equipment engages with an anomaly and is used to properly point a spacecraft's solar panels toward the sun and direct its communications nodes toward ground stations to collect instructions. The satellite remains in orbit.

Industry officials say Lockheed Martin designed the safe-hold software and architecture for both the failed satellite and SBIRS. This classified spacecraft has some similar architectural qualities to that of the upcoming SBIRS geosynchronous spacecraft, which is what triggered a review of its processors and architecture this summer.

The architectural flaw that has proven troublesome is the process by which the attitude control and telemetry units process data and communicate through a common bus. Highly precise timing for communications between the computers is crucial to ensure the safe-hold software can engage as needed. In this case, however, timing for processing various tasks is slow, prompting officials to declare what Air Force Secretary Michael Wynne calls a "no-fly" condition for SBIRS GEO-1.

Though Wynne predicts in a Sept. 26 memo to the Pentagon acquisition czar that this newest SBIRS problem could prompt a one-year delay and a $1 billion overrun, Lockheed Martin's predictions are less dire.

Payton says Air Force officials will know in November the exact extent of the delay and cost impact. To date, SBIRS has experienced five cost overruns of more than 15 percent. Its cost estimate has nearly tripled and now stands at $10.2 billion for three GEO satellites and four payloads designed to piggyback on satellites in highly elliptical orbit.

Hints of this latest problem began early this year, Payton says, when Lockheed Martin began seeing software discrepancy reports on the first GEO spacecraft at its Sunnyvale, Calif., facility. By summer, the number of those discrepancy reports began to outstrip the pace at which officials could remedy them, Payton says. These types of problems generally don't reveal themselves until the spacecraft begins testing in a space-representative environment in the thermal vacuum chamber, he adds.

One government official suggested that Lockheed Martin's decision to shift its program management staff from Sunnyvale, Calif., where the spacecraft are being assembled and tested, to Denver, Colo., could have contributed to the problem. Close, on-sight management might have tackled the problem more aggressively, this source suggests.

Meanwhile, as engineers work on a fix to the processor timing issue, Payton says the team will also continue work on the spacecraft in parallel. This is the main reason why he says the schedule impact may not amount to a full year.

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