UPDATE 2PM: Solo sailor Lisa Blair's world record attempt is over, after her yacht's mast broke in wild Antarctic weather 895 nautical miles from shore early this morning.
Ms Blair was below decks about (3am AEST) when the port shroud broke and the mast came down.
She spent desperate hours clearing the mast from the boat's deck, to avoid further damage to the vessel.
The former Sunshine Coast woman had completed three-quarters of the circumnavigation over 72 days.
UPDATE 11.50AM: Solo sailor Lisa Blair is bruised, shaken and exhausted after struggling through the night with a broken mast, stranded almost 1660km from shore in Antarctic waters.
The experienced adventurer, who grew up on the Sunshine Coast, was 72 days into an attempt to become the first woman to circumnavigate Antarctica solo when her boat's mast broke early this morning.
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EARLIER 10AM: A SUNSHINE Coast woman's attempt to become the first woman to sail solo around Antarctica is in jeopardy after her boat's mast came down at sea.
Lisa Blair was sailing 895 nautical miles (almost 1660km) south of Cape Town, South Africa, through 7m seas and 40 knot winds when the boat's port shroud broke and the mast came down.
She issued a Pan Pan - an urgent alert for assistance (similar to a Mayday) that indicates no immediate danger to her life - about 3am.
Search and Rescue in Cape Town has been notified and will provide assistance if required.
Ms Blair was reportedly well and uninjured at the time of the Pan Pan message.
She was on her 72nd day at sea attempting to be the first woman to circumnavigate Antarctica solo and unassisted.
The demasting came just two days after a hole was torn in the boat's deck.
Ms Blair grew up on the Sunshine Coast, but before her journey was based in Sydney.
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