‘Star Wars’ Sensor Gave False Test Data, Air Force Says

A research satellite launched last week to test elements of the proposed “Star Wars” anti-missile shield failed in a secondary tracking exercise when an optical sensor gave false data to two on-board computers, an Air Force official said Friday.

Air Force Col. John Otten, assistant director of the Strategic Defense Initiative’s kinetic energy office, said an optical sensor on Delta 181, a satellite used to test “Star Wars” sensors and trackers, gave flawed data when it tried to track target objects beyond its range.

Otten said the sensor data went into the computers, causing them to respond inappropriately. He said the flaw was detected within an hour and the computers were told to ignore the data.

Some of the test data on the system was lost, but Otten said the loss was minor because the tracking exercise was a secondary objective. “In the fundamental mission we succeeded,” he said.

12 Hours of Tests

Delta 181 was launched Feb. 8 from the Kennedy Space Center and spent 12 hours conducting a series of tests to gather data needed to refine the SDI, or “Star Wars,” anti-missile system.

Program manager Andy Green last week called the flight “a very successful mission.”

However, Aviation Week & Space Technology, in a story prepared for publication Monday, says the satellite was unable to complete “battle management fire control computations.”

The magazine blamed the problem on the computers, but Otten said the flaw actually was caused by the optical sensor.

Sensors on the satellite were used to track 14 sub-satellite targets released in two groups from the Delta.

Moves Beyond Range

Otten said the problem developed when the optical sensor located an object, looked away and then tried to relocate the original object. By then, the target had moved beyond the range of the sensor.

The tracking test using the optical sensor was halted when the fuel budgeted for that exercise became exhausted, Otten said.

“The tracking anomaly was an important finding for designing any future missile defense because you need to accurately track and update the targets you want to hit,” Green said.