GPS World

Tag: GPS IIA

  • 2 SOPS disposes last GPS IIA satellite after 26 years

    2 SOPS disposes last GPS IIA satellite after 26 years

    News by Airman 1st Class Jonathan Whitely
    50th Space Wing Public Affairs Schriever Air Force Base

    The 2nd Space Operations Squadron at Schriever Air Force Base, Colorado, initiated the disposal of the last operational GPS IIA satellite, satellite vehicle number 34, April 13-20.

    The GPS satellite program currently uses 31 satellite vehicles to transmit precise position, navigation and timing signals to more than 6 billion users around the world. To support the Air Force’s GPS III modernization efforts, 2nd SOPS operators phase out older models to make room for the new GPS III satellites.

    The disposal of SVN-34 marks the end of a 26.5-year era in which the satellite outlived its 7.5-year design life by 19 years.

    “As we continue to manage the influx of GPS III (the newest iteration of GPS satellites) and maintaining other vehicles in a residual status, we have to be cognizant of effective risk management,” said Capt. Angela Tomasek, 2nd SOPS GPS mission engineering and analysis flight commander. “As SVN-34 continued to age, we had to manage its aging components and likelihood of having a critical malfunction. We are at a stage where we are confident in the robustness of the overall GPS constellation to remove the last remaining IIA vehicle.”

    Disposal process. Units conduct satellite disposals when a satellite reaches the end of its operational life and no longer requires daily caretaking and maintenance.

    “We push the satellite vehicle to a higher, less congested, ‘disposal orbit’ to eliminate the probability of collision with other active satellites,” Tomasek said. “[Then,] the vehicle is put into a safe configuration by depleting the leftover fuel and battery life and shutting off the satellite vehicle transmitters so no one else can access the satellite in the future.”

    Once SVN-34 is in its final orbit, 2 SOPS will on April 20 hand over full tracking responsibility to the 18th Space Control Squadron at Vandenberg Air Force Base, California, where it will be treated and cataloged like every other space object.

    “This disposal marks the end of an era in GPS history,” said Lt. Col. Stephen Toth, 2nd SOPS commander. “There are senior leaders and long-time contractors [who] launched and operated the IIA satellites at the beginning of their careers [who] are nowhere to see it end. It is an opportunity to reflect on the legacy and heritage of 2 SOPS and GPS to see how far we have come.”

    Feature image: Artist’s depiction of a GPS IIA satellite in orbit. (Image: USAF)

  • Boeing, US Air Force extend partnership to sustain GPS IIA, IIF

    Boeing and the U.S. Air Force have signed a GPS sustainment agreement to ensure the health of current satellites on orbit. The agreement enables persistent GPS capability for civilians and the military as Boeing works on next-generation GPS satellites.

    Artist's impression of a GPS Block II/IIA satellite in orbit. (Credit: U.S. government)
    Artist’s impression of a GPS Block II/IIA satellite in orbit. (Credit: U.S. government)

    Under the agreement, Boeing will support GPS IIA and IIF satellites on orbit for the next five years. Boeing, which has been the prime GPS contractor for more than 40 years, is now part of the Air Force effort that may lead to the next generation of GPS satellites.

    “This agreement continues Boeing’s strong legacy of GPS innovation and mission support,” said Dan Hart, vice president, Government Satellite Systems. “We are focused on delivering reliable, affordable and resilient GPS capability now and for generations to come.”

    Collectively, Boeing GPS satellites have accrued more than 550 years of on-orbit operation. In March 2016, the company delivered its 50th GPS satellite on orbit to the Air Force and has built more than two-thirds of the GPS satellites that have entered service since 1978.

  • GPS IIA Satellites a Concern for OCX

    One of the long-standing issues for support of IIA vehicles after the future GPS Operational Ground Control Segment’s (OCX’s) ready-to-operate (RTO) date, which should fall in December 2016 at the latest, is what ground command-and-control (C2) system will steer GPS IIA satellites, do navigation uploads, and so on. The issue is that AEP, the current C2 system, will no longer be available once the transition to OCX takes place, and OCX has no requirement to control IIA satellites.

    The OCX program, which struggled early, is now under new Program leadership within Raytheon Space Systems, and while Ray Kolibaba, the new OCX program manager, is making great progress, OCX does not need to be burdened with additional requirements at this stage of the program.

    Just how big an issue is GPS IIA C2? Initially the Aerospace projections were that there would only be one or two GPS IIAs left on orbit in 2017, and it was not worth the costs to include the C2 software for the legacy system in the new software code. However, I have long maintained that Aerospace and Space Missile Systems Command (SMC) neglected to count the residual satellites, maintained by Launch, Anomaly, and Disposal Operations (LADO), which might very well actually amount to 3–4 additional IIAs. Added to the two IIAs on orbit, this could amount to six IIA SVs that need to be maintained.

    The solution announced during the National Space Symposium (NSS, April 16–19) by General William Shelton, the four-star chief of Air Force Space Command, is to fund the current LADO operator, Braxton Technologies, to build in this support for the IIAs. This is significant for several reasons: One of course is that it solves the IIA C2 issues, it does it now, and at a relatively modest cost, and it utilizes more of the capabilities of the Braxton Technologies’ LADO software. Additionally it provides a true backup capability for assets on orbit that become increasingly valuable as the number of available launch slots for GPS decreases.

    Braxton Technologies initially demonstrated this capability years ago in a lifeboat drill during the transition to AEP, but the navigation upload capability was never maintained for LADO after the successful transition. This is certainly a step in the right direction and provides a simple solution to a vexing problem that has plagued the GPS program for the last several years.

    Dual Launch. I asked General Shelton if he would support an approach that would allow the United States to go to dual launch of GPS III on vehicles 5–6 instead of waiting until 8–9 as planned today. He said the Air Force would certainly support that, and is looking at making it possible with vehicle 7 currently. That will come even sooner if the program advances with glitches.

    I also asked him about the gap between GPS III launch and OCX RTO. The gap seems to be getting wider, not narrower, and he agreed that OCX could probably not move to the left, and GPS III has moved significantly to the left, so this is still an issue that needs to be addressed. There are plans in place, but the recent budget activity has caused some uncertainty.

    Sequestration. On the subject of sequestration — a highly charged Congressional effort to force another $500 billion-plus in additional defense cuts — General Shelton said it would amount come on top of the approximately $487 billion already cut from programs, and that many space programs might be unsustainable in their current mode if that occurs.

    However, the U.S. Armed Services have been informed by the White House Office of Management and Budget not to make plans for sequestration. So right now, the services and other agencies of the U.S. government have been forbidden to make programmatic decisions based on a possible sequestration. Interesting.

    By the way, attendance at NSS this year surpassed 9,000.