Evaluation culminates with landings in Brazil last month and USFAA certification looks set to follow soon
Boeing has completed flight tests of a global positioning system (GPS) landing system (GLS) on a Next Generation 737 and is holding talks with several US-based operators to deploy it operationally, possibly by the end of the year.
The GLS, working through a Rockwell Collins multimode receiver, is expected to gain US Federal Aviation Administration certification in the next two months. "It will be available first on the Next Generation 737 models," says Boeing Commercial Airplanes research chief pilot and GLS certification programme project pilot Tom Imrich, who adds the system will eventually be offered on all Boeing aircraft.
The GLS is designed to work with GPS groundstations to provide precision landing capability. The initial certification will cover capability to Category 1, though the long-term goal is to clear it through Cat 2 to Cat 3 autoland "no later" than 2008, adds Imrich. The baseline certification covers test development work for interfacing the GLS with the Rockwell Collins Flight Dynamics head-up guidance system, now available on the 737.
"GLS is now a mature capability and it dovetails nicely with RNP [required navigation performance], which is already in service," Imrich says. "We are looking at what the best options for implementation might be. Initially this will be with special GLS approaches, but we hope that it will develop into a regular full-scale deployment," he says.
Although the FAA's long-term plan to introduce a network of GLS ground stations in the USA under the Local Area Augmentation System programme is uncertain, Imrich says "there are several options available, including privately deployed facilities with authorisation for special approaches." Although the FAA's LAAS plan was re-directed towards a research effort following the elimination of funding for the programme in the 2005 budget, it is believed that studies are under way to revisit the programme.
Flight tests culminated with evaluations in Brazil at the end of August to confirm GLS fidelity in equatorial areas subject to ionospheric interference. The flights included a demonstration of the autoland capability to local carriers around Rio de Janeiro where the GLS-equipped testbed, a Boeing Business Jet, landed within 1m of the runway centreline at Rio's Santos Dumont airport using signals from a GPS groundstation at the international airport 7nm (13km) away.
GUY NORRIS / LOS ANGELES
Source: Flight International
