News Item

GPS satellite's 23rd birthday

GPS Satellite Vehicle Number 23 (SVN-23) celebrated its 23rd birthday on 26 November.

One of the first GPS Block IIA satellites - launched over 20 years ago - SVN-23 represented the latest GPS technology and introduced new sensors and improved processing and memory.

The satellite's design life was 7.5 years - yet it has operated for over 3-times that lifespan. But longevity of service has produced its share of challenges.

In December 1993, 2nd Space Operations Sqn (2 SOPS) operators, analysts and engineers determined that one of the vehicle's solar-array wings had suffered an electronics malfunction - so manual positioning, or slewing, of its arrays had to be employed for many years.

But, by the end of 2001, it was determined that the arrays had degraded to the point that SVN-23 could no longer be operated under a slewing regime. So it was transferred to the other squadron, 1 SOPS, for anomaly and disposal operations - engineers put its solar arrays into dormant mode and turned off the payload.

However, over the next few years, 2 SOPS devised a way to solve the problem. They recalled the satellite from 1 SOPS and powered it back up in June 2007 - and it has been providing GPS signals ever since. Indeed, it features the most accurate time-keeping of any GPS IIA satellite in orbit.

Commander 2 SOPS comments: 'We've reached a point in space operations, much like in the flying community, that our satellites are sometimes older than their operators. I was a member of 2 SOPS as a 2nd Lt when this satellite flew past its design life in 1998. It's simply amazing that a vehicle designed to last 7.5 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.'

Details from Satnews below . .

  • 27 November 2013
  • Space

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