My first emotions in a seagoing submarine were a mixture of fear and exaltation. I was a seventeen-year-old cadet-midshipman ‘sea riding’ in HMAS Oxley as it prepared to fire the first Mark 48 guided torpedo acquired by the Royal Australian Navy from the United States near thirty years ago. When the boat submerged off Sydney heads and we proceeded beyond a depth of six hundred feet, I assumed the strange noises I could hear and the weird sensations I felt were a familiar part of submarine life. While I had complete faith in the very experienced commanding officer, I realised that any catastrophic accident would probably result in the deaths of all seventy-two souls on board.