The cabin cruiser went aground west of Blackrock Tower at about 6.40pm as the tide was going out.
Galway's lifeboat crew launched at 7pm and, on arrival at the scene, two crew members disembarked and swam to the powerboat, where a father and son were still on board.
The lifeboat voluntreers then anchored the boat and escorted the two men safely to Blackrock. Much later that evening the lifeboat returned to the powerboat to refloat it at high water.
Galway RNLI helm David Oliver says the two people were not hurt in the incident. “They were new to boating and it was a lesson learned for them,” he says.
The volunteer lifeboat crew on this callout were Oliver, Dan King, Stephanie Carr and Ian O’Gorman.