Lieutenant Commander Crabtree was commissioned under the V-12 Program at Yale University in 1946. During the Korean War he served aboard USS Torsk (SS-423). He served, successively, as executive officer of USS Kiltiwake, Tigrone, Toro, and Piper, before attending Deep Sea Diving School in 1959. In September 1959, he assumed command of USS Sunbird (ASR-15) and, two years later, became commanding officer of USS Tusk (SS-426). He is currently a student at the Nuclear Power School, Bainbridge, Maryland.