Peter Conway, 48, rushed into the sea when he spotted two of his children, Andrew, 15 and Clare, 20, among eight-feet high waves.

However, witnesses say Mr Conway, who was a director at Rolls Royce, soon appeared to be in difficulties himself.

When a rescuer managed to swim out to the group, he found Miss Conway trying to support her father's head.

There were some people in the water that were trying to help but it was just a very bad situation

James Giminaro, Florida police

A coroner in Florida recorded Mr Conway had suffered a heart attack.

Mr Conway, of Edwalton, near Nottingham, was on holiday at St Augustine in Anastasia State Park when the tragedy happened on 9 August.

Detective James Giminaro, from Florida police, said: "Apparently his children were out in the water and the surf was rough and they started to get into trouble.

"The father then went out to rescue them to get them safely back to shore but he then suffered a heart attack in the water. It was very sad.

"There were some people in the water that were trying to help but it was just a very bad situation."

A spokesman for Rolls Royce in Derby, where Mr Conway had worked for eight years, said: "He made a major contribution to Rolls Royce and he will be very much missed and we extend our deepest sympathy to his wife and family.

"He was widely respected and well liked and it was a great shock to all his colleagues to hear of his death."