Re: Satelittbasert presisjonsinnflyvning på kortbanenettet
Nå er det ikke mange eldre turboprobb som har fabrikksmontert gps utstyr som sammerbeider med FMS systemet. SAAB 340, atp,fokker 50.
Datalink blir installert i alle som ikke har det pga flyet skal kunne komunisere med ATC. Står igså i artikklen at "Yet while regarded as obsolete, and operationally incompatible with GBAS, SCAT-1 today illustrates a nice “back-to-the-future” scenario."
Her er litt mere om disse gps systemene:
http://www.aviationtoday.com/av/issue/feature/Precision-Approaches_74764.html
In very broad terms, the basic concepts of the two systems are similar — each uses a dedicated network of precision GPS monitor receivers dispersed at separate, accurately surveyed locations. In both cases each individual monitor’s incoming “raw” GPS signals are compared with their precisely known positions to determine the actual errors and, ultimately, the correction that should be applied to a user’s receiver at a given location. Only then do the similarities between LAAS and WAAS diverge, due to the way the corrections reach the user’s receivers. In WAAS, a large number of monitors across North America pass their data to a satellite ground station that then continuously loft the corrections up to a geostationary satellite. In turn, the satellite re-transmits them down to all receivers within view, which automatically applies them to their own raw GPS data. In LAAS, which usually employs just four local monitors, the corrections are computed locally and transmitted over a VHF data link to aircraft in the local airspace where, again, the corrections are applied automatically. In both cases, however, the two systems offer the unique capability — assuming obstacle clearance and other airport conditions are met — of being able to provide precision approach service to all an airport’s runways. Furthermore, the LAAS ground station and its supporting monitoring receivers and antennas can be located well away from the runway areas, while WAAS needs neither airport ground equipment nor special avionics.
Both WAAS and LAAS went on to successful certification, with WAAS subsequently achieving major marketing penetration. But LAAS, which met much more demanding certification standards in 2009, has had a harder struggle to win market acceptance. Both also had name changes, following FAA’s adoption of ICAO’s terminology for the two systems. WAAS became the Satellite Based Augmentation System (SBAS), and LAAS became the Ground Based Augmentation System (GBAS).
Well before that, however, GBAS had won strong support from a diverse group of users including Qantas, FedEx and Air Berlin, all of which either had unique approach needs, or anticipated having them in the future. All three built up their GBAS business cases from extensive flight evaluation programs using, in FAA terms, “demonstrably safe” development ground systems from Honeywell, located in Sydney; Memphis, Tenn.; Bremen, Germany; and Malaga, Spain, along with a test systems for Boeing at Moses Lake, Wash., and another at the FAA Technical Center at Atlantic City, N.J. In 2008, the Port of New York and New Jersey purchased and installed a Honeywell ground system at Newark Liberty Airport initially for Continental Airlines. To further evaluate airline “city pair” GBAS applications, the Memphis installation is being moved to Continental’s hub at Houston. Further plans call for evaluation systems to be installed at Rio de Janiero, Brazil and Seoul, South Korea.
On the avionics side, most installations have used “demonstrably safe” Rockwell Collins GBAS receiver modules embedded in multi-mode receivers (MMR), plus VHF data link units, with the complete GBAS package referred to as a GNSS Landing System (GLS). Recently, however, a FAA development contract for future production airborne and ground equipment was awarded to Honeywell under a competitive procurement, while Boeing has announced that all production 737s will carry provisioning for GBAS. Qantas, too, has equipped its 737 aircraft with GLS, and plans the same for its Airbus A380.
The Joint Precision Approach and Landing System (JPALS) is a variant of the civil GBAS for the U.S. military, primarily for U.S. Navy aircraft carriers and helicopter-equipped vessels. JPALS has a number of features, including advanced data link capabilities and specialized avionics, not offered on civil systems.
It will, however, be completely compatible with civil GLS avionics that will be carried by U.S. Air Force aircraft, such as the C-17, to ensure full interoperability with land-based JPALS installations. In 2008, a Raytheon team, including Rockwell Collins and Northrop Grumman, was awarded a JPALS ground station development contract.
SCAT-1: Special Category 1 (SCAT-1) was the nomenclature given to an early GPS precision landing guidance system, prior to the development of requirements for today’s GBAS. Yet while regarded as obsolete, and operationally incompatible with GBAS, SCAT-1 today illustrates a nice “back-to-the-future” scenario.
In 2007, facing the need for reliable operations into some of Norway’s challenging coastal airports that were ringed with high terrain, Wideroe Airlines and Northrop Grumman subsidiary and SCAT-1 developer Park Air cooperated in bringing a system back into service. With the approval of Norway’s regulators and Avinor, the country’s air navigator services provider, the first system was installed at the Bronnoysund airport, 500 miles north of Oslo, and the site of a fatal 1988 accident to one of Wideroe’s aircraft while performing a non-precision approach. Based on SCAT-1’s successful re-introduction at Bronnoysund, Avinor has subsequently installed SCAT-1 systems at 20 remote Norwegian airports with difficult approaches. But because of SCAT-1’s non-conformity, all Wideroe’s fleet of Dash-8s are equipped with specially modified Universal Avionics SCAT-1 receivers.
http://www.flightglobal.com/news/ar...first-approved-precision-gps-approach-219066/
Universal Avionics' GLS-1250 GNSS twin receivers/processors are at the heart of the on-board system, which is totally integrated with the aircraft's flight management system. The airport-located ground station that provides signal corrections and integrity assurance to the aircraft system by VHF datalink was developed by Norway-based Park Instruments.
