The Kilrush RNLI lifeboat was placed on standby on Saturday for a jet that suffered mechanical issues over the Atlantic west of Ireland.
The crew of the Kilrush lifeboat were alerted at 1.55pm by watch officers at the Irish Coast Guard marine rescue sub centre on Valentia Island in Kerry.
Staff there had been informed by air traffic controllers at Shannon that a US-bound American Airlines passenger jet had turned around and could divert to Shannon.
Flight AA-65 was about three hours into its flight from Zurich in Switzerland to New York in the US at the time.
The crew of the Boeing 767-300 jet had been in contact with controllers at the Irish Aviation Authority’s North Atlantic Communications Centre at Ballygirreen in Co Clare at the time.
The flight crew, who had also been in speaking with company engineers, turned around and had initially indicated they wished to divert to Heathrow Airport in London.
About half an hour later, the flight turned around again and continued its journey to the US.
The flight later diverted to Bangor in the US state of Maine.