A ferry sailing to St Malo was diverted on Saturday evening, to help the skipper of a French yacht who had fallen ill.
His daughter made a Mayday call, with the vessel eight miles west of Corbière in heavy swell.
Brittany Ferries' Voyager, enroute from Guernsey, changed course and launched a rescue boat to transfer some of its crew to the casualty boat.
The St Helier RNLI all weather lifeboat arrived on scene to take over and get the yacht, the skipper and his family to shore.
The Voyager continues its journey to St Malo.
Gibby Gordon, Coxswain for RNLI Jersey, said:
"This was a great example of multiple vessels working together to help manage a mayday situation.
"We are extremely grateful to Condor Voyager (sic) and her crew who were first on scene and able to provide immediate assistance.
"Our volunteer crew were able to take over and provide ongoing casualty care and help manage a successful outcome for this family."
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