According to the Daily Express:
The prince flew into action to pilot an RAF Sea King rescue helicopter after the 58-year-old woman plunged down a crevice and broke a leg while trekking in Anglesey. She was flown to hospital in Bangor.
The rescue came less than a week after William and his crew rescued a 16-year-old girl when she got into difficulties in the sea off Anglesey. The schoolgirl, thought to be from Hertfordshire, had been trying to help her 13-year-old sister when she was caught up by the current. He piloted the helicopter while his colleagues pulled the teenager to safety off Silver Bay.