Nav Canada struck a deal with the U.S. Federal Aviation Administration to extend what it describes as the next generation of global positioning systems to aircraft operators flying in Canadian airspace.
Under the agreement,
the FAA’s Wide Area Augmentation System (WAAS) will require Nav Canada to construct four monitoring stations, and result in better GPS navigational performance for satellite-based flight approaches in Canada and in the northern part of the lower 48 states by late next year.
“”Once a carrier identifies a need for a GPS/WAAS approach at a particular airport or airfield that doesn’t have it, then we can do a review of that. And if it is determined that GPS/WAAS is the solution, then what we do is we would need to design approaches,”” said Ottawa-based Nav Canada spokesperson Louis Garneau.
The WAAS has four primary features: monitoring stations installed at certain locations, master stations, uplink stations and geostationary satellites.
The agreement, in which Nav Canada will provide sites and maintainance, covers the installation of monitoring stations in Winnipeg, Iqualuit, and the Newfoundland cities of Gander and Goose Bay. Nav Canada said Canadian WAAS stations will be merged with others in the U.S. and Mexico to provide smooth service in North America.
With the four ground stations, no other ground infrastructure will be needed to design GPS/WAAS flight approaches, which will make airports more accessible to incoming aircraft and translate to cost savings for Nav Canada customers like Air Canada Jazz and WestJet, said Garneau. Designing a flight approach requires approach charts, flight obstacle analyses and flight checks.
Under Nav Canada’s new system, aircraft receivers will use GPS/WAAS signals to pinpoint, lateral and vertical position to within two metres, allowing pilots to fly approaches with vertical guidance in cloud to as low as 250 feet above ground without any approach system infrastructure at an airport. The costs for the new system average about $12,000 for each aircraft.
Carriers and aircraft operators have to determine whether there’s “”a business case for them to use that technology,”” primarily basing the decision on the frequency with which they fly into a certain airport, Garneau said.
The GPS/WAAS system is suited to regional airports without instrument landing systems (ILS), as opposed to major centres like Toronto or Vancouver that have made those investments, he explained.
But Michael Stewart, owner of Business Wings, an aviation management company that’s a tenant at the Toronto island airport, said the WAAS system is aimed at planes flying over mountainous terrain like certain parts of Greenland that are surrounded by canyons.
In contrast, ground-based instrument landing systems installed at many Canadian airports allow descent to 200 feet above the ground in cloud, according to Nav Canada. The downside is that each instrument landing system costs about $1 million.
Nav Canada has been using the global positioning system since the early 1990s, but Garneau explained it doesn’t have “”the same level of accuracy”” that the improved system promises. “”It provides an approach minimum which is very close to what an ILS provides, but without having to put in place a $1-million infrastructure to support it.””
(A minimum is the lowest descent a pilot can take an aircraft before deciding whether to land.)
GPS approaches today don’t provide vertical guidance, and usual minimum altitudes are 100 feet to 300 feet higher than what an ILS allows, which is conducive to more weather-related flight disruptions, said Nav Canada.
Despite the benefits of GPS/WAAS, however, Stewart doesn’t foresee its widespread adoption because an ILS is more reliable. “”It’s bullet-proof. My life is in that radio’s hands.””
Besides, GPS “”can be played with”” compared with the ILS’s system of checks, he said, explaining that last winter the Canadian military in the Petawawa region of Ontario intentionally jammed radio signals. “”Apparently, it can be done with very inexpensive transmitters because the GPS signal is a such a small signal, strength-wise.””
Peter Sands, air operations manager of the Goose Bay Airport in Newfoundland, said his organization is considering investing in the GPS/WAAS system, particularly because a monitoring station is being built by Nav Canada in the region. The move would “”certainly enhance the overall position of Goose Bay”” within Canada and internationally, he said.
If GPS/WAAS is implemented, Sands is uncertain whether the airport’s ILS system will be retained for back-up or whether it may be phased out because it’s seen as redundant.
Goose Bay also has precision approach radar that’s used to help allied military airplanes fly into the area, a landing aid the airport has promised to certain countries that use this system at home. So getting rid of precision approach radar “”might not be an option here,”” Sands added.
What is certain is the biggest winners of bringing a GPS/WAAS system to Canada will be avionics manufacturers, because airplanes haven’t seen upgrades in years, according to Stewart.