Rear Adm. Hancock is a native of Illiopolis, Illinois. He enlisted in the Navy in 1982 serving in Navy nuclear power. He is a 1990 graduate of the U.S. Naval Academy with a Bachelor of Science in Engineering. He also holds a Doctor of Medicine from the Uniformed Services University of the Health Sciences (USUHS).

Operationally, Hancock served as command flight surgeon, Marine All Weather Fighter Attack Squadron 332 (VMFA(AW)); group surgeon, Marine Aircraft Group 31 (forward) in support of Operation Noble Anvil; officer in charge, Marine Corps Air Station Beaufort Health Services; and officer in charge, Fleet Surgical Team 7/Commander Amphibious Group 1 surgeon/Task Force 76. Additionally, he served as task force surgeon, 2nd Battalion, 7th Marines where he developed and deployed the tactical trauma team concept, moving advanced resuscitative capabilities to the point of injury, and subsequently developed, tested, and deployed mobile trauma bays in support of Operation Enduring Freedom (OEF). His staff assignments include command surgeon, U.S. Fleet Forces Command and assistant deputy chief, medical operations, Bureau of Medicine and Surgery (BUMED).

Hancock completed his family medicine residency at Naval Hospital Pensacola and an emergency medicine residency at Naval Medical Center Portsmouth. He served as staff physician and director of medical services, Naval Hospital Beaufort; director of medical services, Naval Medical Center Camp Lejeune; deputy commander, Naval Medical Center Portsmouth; and as commanding officer, Naval Medical Center Camp Lejeune, where he established the Navy’s first trauma center. Additionally, as the Navy and Marine Corps representative to the Chairman of the Joint Chief of Staff Gray Team, he deployed multiple times in support of Operations Enduring and Iraqi Freedom, improving the policy and treatment of traumatic brain injury (TBI). Hancock’s last staff tour was as deputy chief of transition, BUMED. He currently serves as Medical Officer of the Marine Corps/Director, Health Services, Headquarters U.S. Marine Corps (with additional duty as Director of the Medical Corps).

Hancock maintains board certification with the American Board of Emergency Medicine and is a fellow of the American Academy of Emergency Medicine. His academic appointments include assistant professor of military/emergency medicine and assistant professor of neurology at USUHS.

Hancock is qualified as a naval flight surgeon, fleet marine force medical officer, and surface warfare medical department officer. In addition to numerous unit and campaign awards, his personal awards include the Legion of Merit (four awards), Purple Heart, Meritorious Service Medal (four awards), Joint Service Commendation Medal, Navy and Marine Corps Commendation Medal (two awards), Navy and Marine Corps Achievement Medal (three awards), and the Combat Action Ribbon.