A LONE sailor stranded at sea after his mast broke was saved when the passengers of two commercial airliners flying to Sydney spotted him through binoculars.

Drifting for 16 hours in the Tasman Sea, the 44-year-old Queensland man was located about 270 nautical miles off the coast of Sydney after an Air Canada Boeing 777, en route to Sydney from Vancouver, and an Air New Zealand A320, heading to Sydney from Auckland, were called in to help find the missing yachtie.

Up to seven passengers who were travelling with binoculars began scouring the dark ocean for any sign of the man or his vessel.

Around midnight on Tuesday, several of them spotted the sailor sitting on his stricken yacht.

The man, who set off last week to sail from Pittwater to Eden, got into trouble when his mast snapped and the boat became low on fuel.

Police said he activated his emergency beacon about 8am on Monday.

A passenger on the Air Canada flight wrote on Facebook about the amazing discovery at sea: "15 hour flight ends up being 17 hours as we descend to 4000 ft to locate a capsized yacht for search and rescue," the passenger wrote.

"Amazing, and slightly off-putting, to see what a Boeing 777 aircraft can do when not on autopilot and flying/circling low over the ocean.

"Found the boat thanks to people who bring binoculars in their carry-on (yup, like 6-7 sets onboard), and we're now home safely."

An Australian Maritime Safety Authority spokeswoman said the sailor was not injured during his ordeal.

He is presently aboard a NSW Water Police launch and is due back on land today.

Stephen Hosking, from The Quays Marina at Church Point, said the yachtsman had obviously been in a "fair amount" of trouble to fire the emergency beacon.

"We're told the EPIRB is the absolute last resort when we're out on the water," he said. "He must have been in trouble and would have tried absolutely everything before setting it off. Either that or he's an idiot."

Police said the man will not be back on land until around midday, with wild weather delaying his return to the NSW Water Police base at Balmain.

Originally published as Passing Air Canada jets save sailor