Sydney: An American teenage solo sailor who went missing in rough Indian Ocean seas has been found safe and well with her damaged vessel, her father said on Friday.

Abby Sunderland, 16, was spotted by an Australian search plane after 0600 GMT on Friday, after she ran into trouble in a remote part of the ocean and triggered emergency beacons.

"She's fine, the boat's afloat and she's on it," Laurence Sunderland told Australia's public broadcaster ABC. "It's huge, fantastic, exciting news."

Sunderland lost satellite phone contact with her family in California early Thursday before she manually activated the beacons. Her father said the yacht had lost its mast.

Australian rescue authorities had warned of "extremely poor" conditions in the remote part of the ocean where Sunderland was drifting, with 90-kilometre (60-mile) per hour winds and six metre (20-foot) swells.

She was located by a chartered passenger jet which flew out of Perth, some 3,700 kilometres (2,300 miles) away on the west coast of Australia, carrying rescue experts including trained spotters.