At press time, technical experts from the FAA, the U.S. Coast Guard and researchers from Ohio and Stanford Universities were due to begin a two-week flight-test program in Alaska to assess the use of loran transmitters to send out GPS WAAS messages across the state.
Satellite navigation systems
The FAA is preparing publication of the first LPV (lateral precision with vertical guidance) approaches, a new type of precision approach procedure designed specifically for WAAS. The hallmarks of LPV are lower landing minimums than Lnav/Vnav (250 ft and three-quarters of a mile visibility) and signals that are compatible only with IFR-approved WAAS receivers.
The Wide Area Augmentation System (WAAS) successfully passed a critical 60-day test that prime contractor Raytheon said proves the reliability of the signals for ILS-like approach procedures to thousands of airports not served by precision instrument approaches.
After extensive industry consultation, the FAA has recently completed a document outlining its proposed strategy for transition from today’s terrestrial navaids to GPS, including proposed procedures to minimize the effect of GPS jamming.
Navstar, the official U.S. Air Force program moniker for the constellation of satellites most of us refer to simply as GPS, has undergone a multitude of technical changes and upgrades in the nearly 30 years since a group of military and civil engineers first sat down in the Pentagon to talk about the far-reaching precision navigation concept.
The FAA’s original plan to transition to sole-means GPS is no longer practical and some form of backup will be required for the foreseeable future, according to speakers at a recent Navigation Industry Day. This event was sponsored by the DOT, FAA and Civil Aviation Advanced Systems Development (CAASD), which is a component of the federally-funded MITRE research and development center and a key FAA think-tank resource.
Honeywell last month announced it has signed a collaborative agreement with Lockheed Martin Air Traffic Management in Rockville, Md., to jointly compete for an FAA contract for local-area augmentation system (LAAS) hardware and support. The FAA is expected this month to award a contract for the initial production and installation of LAAS ground stations at six airports, with an option for 15 to 40 more per year over the next five years.
The Department of Defense is conducting more GPS interference tests in the western U.S. through next month that will cause GPS navigation to be unreliable at times near the test centers, reported AOPA. The areas affected center on the Bonneville (BVL) Vortac in Utah, Truth or Consequences (TCS) Vortac in New Mexico and Sierra Vista Municipal Airport in Arizona.
Goers and GOTS describe two critical FAA programs planned for later this year and early next year, respectively. Goers stands for GPS outage en route simulation, while GOTS is similar, but with terminal replacing en route.
Speakers from Eurocontrol and the European Space Agency last month informed attendees at a meeting of the FAA’s Satellite Operational Implementation Team (SOIT) that their organizations would accept liability for system failures when the Galileo satnav system was used in critical applications requiring high-accuracy guidance, such as approach and landing operations.