Reports of a capsized vessel in the Clyde and a person in the water in rough seas north of Largs resulted in an emergency call out for the lifeboat.
The coastguard put out the alert at 4.25pm on July 27.
Lifeboat spokesman David Hewitt said: "There was a report of a capsized sailing vessel with the possibility of person in the water 2 miles north of Largs.
"The lifeboat proceeded at best possible speed in rough sea conditions with a Force 6 gusting 7 north west wind."
"The lifeboat located the vessel which was under sail and found all well onboard".
David added: "When observed from the shore the first informant saw the vessel slowly tacking about 150metres offshore and this gave the impression that the vessel was in difficulty.
"This service was deemed a false alarm with good intent and the RNLI would like remind people that should they see an incident that gives them concern they should call the coastguard using the 999 system."
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