Australia deploys GPS for pinpoint landings

NASHVILLE, Tenn.—Australia will become the first country worldwide to use the $10 billion, U.S.-built Global Positioning System to help aircraft make precision landings when it inaugurates next month an enhanced GPS-based landing system on tiny Norfolk Island, 938 miles east of the Australian continent.

Norfolk Island has a Local-Area Augmentation System that will enhance the accuracy of GPS signals so that pilots can pinpoint within a meter their exact location, according to Bill Ely, operational test and evaluation specialist for AirServices Australia, which served as a consultant on the project.

The GPS LAAS gear was augmented by computers, radios and GPS receivers that help correct for errors in the GPS signal and also monitor the functioning of the 24-satellite constellation.Australia installed GPS LAAS on the island, which measures two miles by five miles, rather than a traditional instrument landing system (ILS) that relies largely on expensive hardware.An ILS system for Norfolk Island would cost about $6 million, while the LAAS cost between $600,000 and $700,000, Ely said, speaking here at the Coast Guard conference sponsored by the Civil GPS Service Interface Committee. The conference is a semiannual meeting of worldwide civil users of GPS technology, which was originally developed by the Defense Department for military use.

Norfolk Island, discovered by Capt. James Cook in October 1774—or 255 years before the LAAS GPS service will start operation—is heavily dependent on tourism and needed low-cost landing aids, Ely said. "It's a piece of rock that sits in the middle of the Pacific Ocean...subject to sea fog, and if a plane cannot land, it's in deep trouble," he said.

Ely said that FlightWest, the main Australian carrier serving Norfolk Island—which is home to descendants of the HMS Bounty mutineers who moved there in the mid-1800s—racked up $40,000 (Australian) in costs per month because of flights that could not land on the island and had to return to the continent.

The Federal Aviation Administration plans to install LAAS systems throughout the United States, Ely said, but so far the agency has only tested it in nonoperational modes.