Jim Christley retired from the US Navy in 1982 as a senior chief petty officer having served on seven submarines ranging from diesel to nuclear fast attacks to ballistic missile boats. A student of US submarine technical history, he has written numerous articles and a book on the subject in addition to providing technical illustrations to several notable books on submarine design and history. Jim is a resident of Lisbon, Connecticut. Peter Bull graduated from art college in 1979 and has worked as a freelance illustrator for over 25 years. He has created both traditional and digital art for publishers worldwide, and also runs the Peter Bull Art Studio, based in East Sussex, UK, which he founded in 1975.