Did you know…
What was the Douglas F6D Missileer?
Short answer
A carrier-based fleet air defense fighter that Douglas designed for a 1959 US Navy requirement and that was never built. It was meant to loiter far from the carrier and shoot down hostile aircraft at 160 km (100 miles) with its radar and long-range missiles. It was canceled in December 1961.

A 1959 idea
Douglas conceived the F6D Missileer as a carrier-based fleet air defense fighter, in response to a 1959 US Navy requirement. The approach was a subsonic platform that would loiter on station along the threat axis, carrying a huge long-range radar and up to eight very-long-range air-to-air missiles. Its job was to patrol for extended periods well away from the Navy's aircraft carriers and engage hostile aircraft at 160 km (100 miles) using that radar and those missiles. It was also meant to be able to operate from Essex-class carriers and remain on station for four hours at 35,000 ft.
Big radar, long missiles
The nose was bulbous because it had to house the dish of the Westinghouse AN/APQ-81 radar, five feet in diameter. The normal load was six missiles, all under the wings, and two more could be carried under the fuselage, which increased the maximum takeoff weight by 4,800 lb. The Eagle missile was accelerated after launch to Mach 3.5 by a large solid-propellant rocket booster and, after a glide phase, a long-burning sustainer motor slowly raised its speed to Mach 4.5.
Why it never flew
Critics within the Navy argued that, once it had fired its missiles, the Missileer would be completely unable to defend itself and would have to return to the carrier as soon as possible to rearm. Those arguments eventually prevailed and, combined with the desire to cut military spending in pursuit of a balanced budget, led to the F6D's cancellation in December 1961. When the F-111B ran into intractable problems as an air-to-air fighter and in carrier operations, the same systems were installed in the F-14 Tomcat.
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