by Scott Prater
11/26/2013 - SCHRIEVER AIR FORCE BASE, Colo. -- As
members of the 2nd Space Operations Squadron recognize and celebrate
Global Positioning System Satellite Vehicle Number-23's 23rd birthday
Nov. 26, they'll do so with fond memories of the satellite's service to
military and civilian users throughout the world.
Launched on Nov. 26, 1990, SVN-23 gave military and civilian users
another tool for determining position, navigation and timing, but during
its 20-plus-year life, it also represented the GPS team 2 SOPS'
ingenuity, innovation and problem-solving abilities.
One of the first GPS Block IIA vehicles to reach orbit, SVN-23
represented the latest GPS technology and introduced new sensors and
longer lasting data processing memory.
Ted Mogey worked in the squadron as a contractor engineer and Mark Drake
served as a satellite vehicle operator. Mogey and Drake powered up
SVN-23's payload for the first time in 1990 and still support the
This is more than another birthday. Boeing engineers designed SVN-23 to
perform its duties for more than 7 years. In operation for more than
three times its expected life, SVN-23 still orbits Earth twice every
day, providing position, navigation and timing to approximately 3
billion users worldwide.
Its longevity of service has had its share of challenges.
On Dec. 23, 1993, 2 SOPs operators noticed something amiss. Analysts and
engineers in the squadron eventually determined that one of the
vehicle's solar-array wings had suffered an electronics malfunction, so
manual positioning [or slewing] of its arrays ensued for many years.
"Remarkably, the 2 SOPS/2nd Space Control Squadron team kept finding
ways to keep the satellite operating," said Lt. Col. Matthew Brandt, 2
SOPS director of operations. "By the end of 2001, they determined the
arrays had degraded to the point that SVN-23 could no longer be operated
under a slewing regime."
The vehicle was transferred to the 1st Space Operations Squadron for
anomaly and disposal operations. Engineers put its solar arrays into
dormant mode and turned off the satellite's payload.
During the next few years, however, 2 SOPS team members figured out a
way to solve the problem. They recalled the satellite from 1 SOPS and
powered the payload back up in June 2007.
It has been providing GPS signals ever since. In fact, it features the
most accurate time keeping of any GPS IIA vehicle on orbit.
"We've reached a point in space operations, much like in the flying
community, that our satellites are sometimes older than their
operators," said Lt. Col. Thomas Ste. Marie, 2 SOPS commander. "I was a
member of 2 SOPS as a second lieutenant when this satellite flew past
its design life in 1998. It's simply amazing that a vehicle designed to
last seven and half years has made it to its 23rd birthday. It is a
credit to the operators, analysts, maintainers and engineers on both the
government and contractor sides who all worked to diligently to
preserve its mission capabilities."