A missing American sailor whose abandoned boat mysteriously ran aground in Australia on Saturday was on a round-the-world journey and had plans to meet a romantic interest in the Philippines.

Retired engineer Hartwell Champagne Jr, 62, set sail from Panama in Central America on January 27 aboard the Ocean Rambler, stopping in at Pacific islands along the way.

Queensland Police are piecing together Mr Champagne's movements between his last known communication at sea on September 10, and the night his abandoned boat was found beached at Cape Bedford, near Cooktown, on September 13.

The boat still had a foresail set on a whisker pole, and the mainsail was lashed to the boom.

Police have not launched a search as experts have advised them it would be impractical due to the size of the area

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