The McDonnell F-101 Voodoo was a supersonic military fighter flown by the USAF and the RCAF. Initially designed as a long-range bomber escort (known as a penetration fighter) for the Strategic Air Command (SAC), the Voodoo was instead developed as a nuclear armed fighter bomber for the Tactical Air Command (TAC), and as a photo reconnaissance aircraft based on the same airframe. Extensively modified versions were produced as an all-weather interceptor aircraft, serving with the Air Defense Command, later renamed the Aerospace Defense Command (ADC), the Air National Guard, and the Royal Canadian Air Force, later renamed the Canadian Forces.