William sleeps underwater

Prince William secretly spent 24 hours on a nuclear submarine.

The royal – who turns 26 tomorrow (21.06.08) – was taking part in a training exercise to track down and destroy another vessel.

He reportedly spent the night on board HMS Talent on Tuesday (17.06.08) as part of his two-month attachment to the Royal Navy.

William – known as known as Sub Lieutenant William Wales – was said to be “fascinated” by the experience, which saw him spend time in the control room, the nuclear reactor and in the torpedo room before being winches off the vessel by a Sea King helicopter.

A source said: “Prince William has huge respect for what submariners do and the sacrifices and discomfort they put up with. He was very keen to see what their life was like.”

William, who is second in line to the throne, has also had attachments with the army and Royal Air Force.