The fighter designation F-99 was assigned in the late 1940s to the Bomarc surface-to-air missile. The F-99 was a joint project of the Boeing Airplane Company and the Michigan Aeronautical Research Center, the name *BOMARC* standing for BOeing and the Michigan Aeronautical Research Center.
The Bomarc missile resembled a small aircraft, with a pair of shoulder-mounted delta wings. It was launched from a vertical position by a 23,000 lb.st. Aerojet General LR59-AG-13 liquid-fueled rocket motor mounted in the tail. Second-stage thrust was provided by a pair of 10,000 lb.st. Marquardt RJ43-MA-3 ramjet engines attached to the fuselage sides. Maximum speed attained during an intercept was Mach 3.45 (2275 mph) at 105,000 feet. Launch weight was 15,500 pounds. The dimensions were wingspan 18 feet 2 inches, length (excluding the first stage rocket nozzle) 47 feet 4 inches, height 10 feet 3 inches, wing area 65 square feet.
The warhead consisted of 1000 pounds of high explosives. Alternatively, a nuclear warhead could be carried. The warhead was detonated by a proximity fuse activated from the ground control center.
The first Bomarc launch took place on September 1, 1952. A short time later, it was decided that it was not a good idea to give fighter designations to unmanned missiles, and the Bomarc was redesignated IM-99A, where IM stood for "Intercept Missile".
The IM-99B version of the Bomarc had a first-stage Thiokol solid-fuel rocket motor in place of the liquid-fueled engine of the A.
On September 18, 1962, the IM-99A and B were redesignated CIM-10A and CIM-10B, where the C prefix stood for "Coffin" which described the intercept missile's launch environment, i.e. horizontal storage in a protective encounter.
The Bomarc served well into the 1960s with the USAF Air Defense Command.
In the late 1950s, the Canadian government decided to abandon work on the advanced Avro Arrow two-seat Mach 3 interceptor and opted for the unmanned Bomarc. The Bomarc served in Canada for about a decade. At first, the warheads were conventional, since the Canadian government of the day (Progressive Conservative Party) could not decide whether to accept nuclear warheads or not. When the Liberal Party came into power in 1963, the government finally decided to accept nuclear warheads. The nuclear warheads were supplied by the US, and there was a "double key" launching arrangement similar to that used by US missiles in the United Kingdom. The warheads were removed and returned to the USA in April/May of 1972, and the missiles were decommissioned at the same time.
A CIM-10A Bomarc (serial number 59-1897) is on display outside the USAF Museum at the Wright-Patterson AFB in Ohio.