Submariners from the nuclear submarine HMS Victorious got a surprise when it was announced that Iron Maiden singer Bruce Dickinson was on board. As an international rock star, he's conquered land. As a licensed pilot, he's conquered the sky. And now ... the sea?

The metalheads on board were surprised that Dickinson came prepared and seemed very knowledgeable about the sub. He was allegedly invited by the captain to spend three days experiencing first-hand what it's like to live and work on board a nuclear submarine. Now that he's not moonlighting as a pilot anymore, could Dickinson be searching for new frontiers?

He was also a gentleman, a submariner says: "He was extremely down to earth and hung around with everybody asking questions and chatting about his life. ... Everyone was happy to have him on board with us. Lots of people were stunned by it but some didn't know who he was."

If the next time we heard about the rocker's legendary extracurricular activities he's aboard an international space station, we wouldn't be surprised.

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