The third SBIRS satellite, the next satellite scheduled to join the U.S. Air Force’s Space Based Infrared System (SBIRS), pictured above in final assembly and test at Lockheed Martin in Sunnyvale, California. Credit: Lockheed Martin.

WASHINGTON – The U.S. Air Force has indefinitely pushed back the Oct. 3 launch of a Lockheed Martin-built missile warning satellite after a supplier told the company that one of its components “experienced an anomaly” on an unspecified satellite.

That same type of part also was on the third satellite in the Air Force’s missile-warning constellation known as the Space Based Infrared System.

Lt. Gen. Samuel Greaves, the head of the Air Force’s Space and Missile Systems Center, tweeted Sept. 10 that the launch had been delayed.

In a response to questions from SpaceNews and citing a non-disclosure agreement, the Air Force declined to identify the other satellite except to say that it was not part of the SBIRS constellation. Lockheed Martin, the program’s prime contractor, also declined to identify the satellite, except to say that it did not build the space vehicle that experienced the problem. This rules out any potential anomalies with the fifth of the Navy’s Mobile User Objective System satellites, which Lockheed Martin built and is now struggling to reach its intended orbit.

“Lockheed Martin was notified by one of its suppliers that a supplier-manufactured component had experienced an anomaly on another non-SBIRS satellite,” Greaves said in an Aug. 13 email. “The same type of component is installed on the SBIRS GEO Flight-3 spacecraft. The Air Force and Lockheed Martin teams are conducting a thorough investigation to evaluate whether the component issue affects the SBIRS satellite and determine what steps must be taken to resolve any issues before launch.”

Neither Lockheed Martin nor the Air Force identified the supplier.

A new launch date has not been set, Greaves said, but the delays gives Air Force engineers “time to investigate a potential parts issue that arose on another program.”

“The Air Force and Lockheed Martin are reviewing the issue and diligently working to determine if there really is risk of program impact,” Lauren Fair, a Lockheed Martin spokeswoman told SpaceNews. “We are confident that these rigorous engineering steps will provide us with a path forward.”

The first two satellites in the $19 billion SBIRS constellation launched in 2011 and 2013 respectively. The Air Force also has missile-warning sensors hosted aboard military satellites in elliptical orbits.

Mike Gruss covers military space issues, including the U.S. Air Force and Missile Defense Agency, for SpaceNews. He is a graduate of Miami University in Oxford, Ohio.