http://www.telegraph.co.uk:80/et?ac=001884957739185&rtmo=rhQh99FX&atmo=99999999&pg=/et/99/8/16/nsat16.html

Millions of satellite navigation devices set to fail By Robert Uhlig, Technology Correspondent

MILLIONS of navigation devices around the world face the threat of failure at midnight next Saturday when a global satellite network is hit by its own version of the Millennium bug. Experts are worried about the risk of accidents to light planes and sailing boats.

Fear of the "end-of-week" bug has prompted government agencies in America to alert pilots, sailors, as well as drivers, climbers, hikers and others who rely on the Global Positioning Satellite system. Warnings have also been issued by the International Maritime Organisation and Ireland's minister of marine and natural resources.

But in Britain, where such devices are common and where the Ministry of Agriculture, Fisheries and Food will require all fishing vessels over 24 metres long to carry GPS monitoring terminals from 2000, no official warnings have been issued. This is despite the fact that the bug could disable systems and endanger life as planes and boats approach air and seaports.

A spokesman at the Department of the Environment, Transport and the Regions said: "It is an American system and people chose to buy into it, so it is their look-out." He said that the ministry had known about the problem for some time and was relying on "information filtering down to the owners of private aircraft" and other amateur users from aeronautical information circulars.

He said: "There is the risk that for a short period equipment could be giving out wrong signals, but I understand that the equipment does right itself." He added that the department had "no obligation" to warn users. The US Defence Department, which runs the GPS network, or the Federal Aviation Authority was responsible.

The bug has arisen because the GPS system, a constellation of 24 satellites around the globe, keeps track of time by counting the number of weeks since it went into operation in 1980. The counter, which allows for about 20 years' worth of weeks, computes up to 1,023. At midnight next Saturday, week 1,023 ends and the counter rolls back to zero.

An American congressional sub-committee heard in May that, while military, space and most commercial systems were well prepared, small businesses and amateur users could be hard hit. Keith Rhodes, technical director in the Office of the Chief Scientist, told the sub-committee: "The satellites will not fall out of the sky and will not lose their power. The problem will be on the ground, with what you hold in your hand."

Hand-held receivers such as those popular with mountaineers, sailors and some motorists were "probably going to have a problem" if they were more than five years old.

A notice issued by the United States transport department said: "Consumers who depend on GPS at sea, on land or in the air may experience one of these problems with their receiver: it will be unable to locate the satellites, resulting in the receiver not working; it will take more time than usual to locate the satellites; it will appear to be working but display inaccurate positions, times or dates."

David Rowlands, a senior official at the British transport department, told a Commons select committee last November that receivers affected by the bug "would not generate false readings but would simply fail".

The Ministry of Defence said that it had completed all the necessary fixes to its equipment. A spokesman said: "We will not have any problems. GPS is used extensively, but as a complementary system. We have updated all systems as necessary, including cruise missiles on submarines."

Civilian GPS receivers have been available for about 10 years and are routinely built into cars, sailing boats, light aircraft and even London taxis. They cost as little as #100 and are now being incorporated in watches and mobile telephones.

Each of the 24 satellites in the system carries an atomic clock from which it transmits a continuous time signal. By comparing the time signals from at least three satellites, a receiver can use triangulation to work out its position on Earth to an accuracy of 30ft. As with the Millennium bug, nobody knows exactly how far-reaching the consequences of the atomic clocks resetting themselves to week zero will be to the navigation devices.

John Lovell, director of quality for Trimble Navigation Ltd, the leading maker of GPS devices, said that products bought in the past three to five years would not have any serious problems. He said: "There is a very small chance of a navigational error, but not zero. Everyone should check with the manufacturer to make sure."

Garmin and Magellan, two other leading makers of GPS equipment, have posted information for their customers on their web sites. Garmin issued a warning that some of its older products might need "to perform an 'autolocate' or 'search the sky' operation to acquire satellites and perform navigation functions after the GPS week number rollover occurs".

The company said also that its equipment could malfunction when used in conjunction with other incompatible equipment, data or software, such as electronic charts or auto-pilot systems. Magellan, which has sold more than a million receivers since 1989, has been testing all its current and discontinued receivers, starting with the most recently released products.

It described the task of testing more than 100 products as "an enormous and an important one". With less than a week to go, only 51 of its products are listed on its web site as "end-of-week compliant". People with products not judged to be compliant are advised to contact Magellan, which will determine whether the product should be fixed or modified.

Nigel Waterson, the Tories' transport spokesman, condemned the Government for not taking a more active role in warning the public. He said: "It is potentially a very irresponsible attitude. We may be talking about the safety of yachtsmen and other British users. Whatever the origins of the satellite system, it is not something that ministers can wash their hands of."

-- fred S. (working@tpost.y2k), August 16, 1999

Answers

"Wolf! Wolf!"

-- Lane Core Jr. (elcore@sgi.net), August 16, 1999.

Working with Trimble GPS units, I am going to be intersted in what happens for the follwing reason.

WNR (Week number rollover) affects a incredibly small number of machines compared to Y2K. Also, most makers like Trimble have offered extensive information and updates/fixes (if possible). It'll be interesting to see how many people/organizations took advantage of the fixes or replacements that are readily available.

If not much happens, thats the way it SHOULD be. This is a SMALL problem compared to Y2K, and you don't have to be very technologically astute to get your unit or system fixed.

If there are significant problems, it would show that people will not even fix easily correctable problems in advance and therefore, to me, would confirm the worst fears of any Y2K doomer.

-- Jon Johnson (narnia4@usa.net), August 16, 1999.

Will the problems be significant enough to warrant media attention or will they be brushed under the rug?

-- Linda A. (adahi@muhlon.com), August 16, 1999.