We have heard it before, in various fora and in various forms: the GPS program is a victim of its own success. Because the satellites are living so long, launches of new, modernized space vehicles get deferred. And deferred. And deferred. The U.S. Congress meanwhile, for whom “defer” is a code to live by, happily pounces on this as an excuse to cut the GPS budget. And cut again the next year. And cut again.
As my colleague Eric Gakstatter reported from the Civil GPS Service Interface Committee (CGSIC) States and Local Government Subcommittee meeting, August 17, in Seattle:
“Of the 12 Block IIF GPS satellites being built, two are in orbit with the first being launched in 2010 and the second one last year. A third is scheduled to launch later this year [On October 4, in fact, perhaps by the time you read this column —Ed]. That equates to one launch per year.
“Clearly, this pace cannot continue or it would be 2022 before all 12 IIFs were in orbit. What’s the problem?
“Part of the problem is that the legacy Block IIA model satellites have performed so well. In fact, one has been operational for 22 years. That’s an incrediblefeat for a satellite that was designed with an expected life of 7.5 years. Unfortunately for the IIF program — and for the high-precision user community — it means that Congress can defer a few hundred million dollars per year by delaying the IIF launches. In these budget-conscious economic times, it’s not difficult to understand the reasoning that if there are 31 operational GPS satellites in orbit, why spend $150–200 million to launch each GPS satellite when we don’t need it yet? But that won’t last for long. The many legacy GPS satellites are one component failure away from being unusable. That said, the word at the CGSIC meeting is that three IIF satellites will be launched in 2013.”
An energetic online discussion sprang out of this column, with one reader exclaiming, “Finally someone stops arguing that the launch segment is the bottleneck. The budget segment is the actual bottleneck!”
The point is well taken. Since inception of the system, the standard text is that GPS consists of three inter-related segments: space, ground, and user equipment. Actually, there is a fourth segment, every bit as important as the other three: the budget segment.
It takes all four to deliver a PNT solution.
Engineers across the GNSS community industriously modernize the space vehicles, the ground control systems, and make leaps and bounds in überupgradesof receivers, chips, antennas, software, and just about everything else you can think of. And this is not just for GPS, but for GLONASS, Galileo, Compass, and QZSS too.
Meanwhile funding bodies grind along with the same ol’ same ol’.
The nation needs a next-gen legislature.