Experts fear non-compliant Global Positioning System (GPS) devices could erroneously reset their clocks to January 1980 when their timing systems revert to zero.
"It could potentially be fatal," said Peter Gibson, a spokesman for the Civil Aviation Safety Authority.
"Instead of being where you think you are, you could be 40 kilometers (24 miles) away," he said. "The first you know about it would be 'ka-boom' -- when you fly into a mountain range."
While Australian aircraft were safe, because they must rely on alternative navigation methods, aircraft or boats in other countries may not be, Gibson said.
That concern led the Australian government to issue a rare warning on the dangers of travelling with "smaller overseas airlines."
"It would be prudent for Australian travelers not to travel on smaller overseas airlines in remote locations from August 19 to 24," the Foreign Affairs Department said in a statement.
Such airlines "could be exposed to potential malfunctions or failures during that period."
Between August 19 and 22, the 24 satellites of the Global Positioning System (GPS), which provide navigational data from 17,600 km (11,000 miles) out in space, switch their timing system back to zero.
Experts say that when the rollover, or return to zero, happens, up to 1.5 million of the 10 to 15 million GPS devices in use around the world may be unable to handle it and fail. When the system began operating in January 1980 it was designed to record time for 1,024 weeks.
The possible glitch, dubbed the "end of week bug," promises to be a dress-rehearsal for the millenium bug which may cause some computers to mistake the year 2000 as 1900 come January 1 because of an old programming shortcut.
The Australian Maritime Safety Authority, which covers a swathe of the Pacific, Indian and Southern oceans almost the size of Russia, said it was not ringing alarm bells too loudly.
"We're not overly concerned, though there's some concern about old fishing boats or yachtsmen who don't do a lot of maintenance on their boats," said spokesman David Gray.
"If they are only relying on GPS and not navigational charts they might be slightly off-course. In areas that are tight, like the Barrier Reef areas, they could go aground."
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