Atlas V 401 (NROL-36) - VAFB - 13.9.2012

The lineup of Atlas 5 rocket launches this month -- a national security satellite deployment from California and a NASA space weather research project from Florida -- will flip-flop in order to give the Air Force more time to sort out Range instrumentation troubles that stalled the West Coast blastoff originally planned Aug. 2.

That puts the Aug. 23 launch of the Radiation Belt Storm Probes from Cape Canaveral next in the firing order. The rocket has been assembled and will be topped by tandem spacecraft on Thursday.

At Vandenberg Air Force Base, meanwhile, engineers continue their analysis and troubleshooting to understand a problem with the Western Range that cropped up late in the countdown on Aug. 2. The issue scrubbed the rocket's attempt to launch that day and the vehicle remains grounded awaiting a new liftoff date.

"During (the) countdown, Western Range Operations Control Center safety personnel identified an issue in the Mission Flight Control Center. The center processes radar, optical and telemetry data from instrumentation sites located on and off Vandenberg and displays and processes commands for the mission flight control officer, whose main responsibility is to terminate the flight of the launch vehicle should we need to for public safety reasons," the Air Force said in a statement to Spaceflight Now.

"Because public safety is the primary concern of the 30th Space Wing, we stopped countdown once the issue was identified."

Hoping the Range trouble would be fixed sooner rather than later, officials tentatively retargeted the launch for Aug. 14 or 15, the last opportunities to perform the California mission without impacting the Florida flight on Aug. 23.

The time necessary to complete the review of data from one launch before granting clearance to the next one requires about a week between missions.

But in meetings this week, the decision was made to stand down from the California launch for now and focus on getting the Aug. 23 flight performed for NASA.

"The Mission Flight Control Center is a complex and interdependent center comprised of 80 plus servers, 8 operating systems and thousands of software processes," the Air Force says.

The work to resolve the problem "will require in-depth engineering support to not only identify the cause of the malfunction but to correct, test and certify the center for operations."

Although the Vandenberg launch does not have a new launch date, the math says Aug. 30 would be the soonest it could occur, pending resolution with the Range.

Whenever that rocket does launch, it will carry a classified payload for the National Reconnaissance Office known as NROL-36.