Still Evolving

Air Force Space Command says it is making another software upgrade to the Global Positioning System ground control segment. This new software release, known as architecture evolution plan 5.5D, builds upon the AEP 5.5C update made back in January, and is primarily meant to support the upcoming launch of the first GPS Block IIF satellite expected around May. Unlike AEP 5.5C, the new upgrade “does not affect any user interfaces, and therefore should be transparent to the end user,” said Col. David Buckman, chief of the positioning, navigation, and timing division within AFSPC’s requirements directorate. Some military GPS receivers did not function properly after the January upgrade. Gen. Robert Kehler, AFSPC boss, said in mid February the issue had to do with the receivers and not the GPS software. A fix was in the works then for the receivers. (Peterson release)