Pushing the Limits

Vice Admiral Allan Rockwell McCann left no reminiscences that might reveal a deeper sense of his extraordinary service, but naval historian Carl LaVO has filled that void by writing this revealing—and often inspiring—biography. Among McCann’s many accomplishments: Served as liaison officer for the modification of the antiquated O-12 submarine into the privately-leased Nautilus that made the first attempt to sail beneath the Arctic ice shelf in 1931; pioneered the McCann Submarine Rescue Chamber;