The North American F-107 is North American Aviation's entry in a United States Air Force tactical fighter-bomber design competition of the 1950s. The F-107 was based on the F-100 Super Sabre, but included many innovations and radical design features, notably the over-fuselage air intakes. The competition was eventually won by the Republic F-105 Thunderchief, and most of the F-107 prototypes ended their lives as test aircraft. One is on display at the National Museum of the United States Air Force and a second at Pima Air and Space Museum.

In June 1953, North American initiated an in-house study of advanced F-100 designs, leading to proposed interceptor (NAA 211: F-100BI denoting "interceptor") and fighter-bomber (NAA 212: F-100B) variants. Concentrating on the F-100B, the preliminary engineering and design work focused on a tactical fighter-bomber configuration, featuring a recessed weapons bay under the fuselage and provision for six hardpoints underneath the wings. Single-point refuelling capability was provided while a retractable tailskid was installed. An all-moving vertical fin and an automated flight control system were incorporated which permitted the aircraft to roll at supersonic speeds using spoilers. The flight control system was upgraded by the addition of pitch and yaw dampers.


A side-view of North American F-107A #2 55-5119 at the NMUSAF.
The aircraft's most distinguishing feature is its dorsal-mounted variable-area inlet duct (VAID). While the VAID was at the time a system unique to the F-107A, it is now considered to be an early form of variable geometry intake ramp which automatically controlled the amount of air fed to the jet engine. Although the preliminary design of the air intake was originally located in a chin position under the fuselage like the Vought F-8 Crusader, the air intake was eventually mounted in an unconventional position directly above and just behind the cockpit.The VAID system proved to be very efficient and NAA used the design concept on their A-5 Vigilante, XB-70 Valkyrie and XF-108 Rapier designs.

The air intake was in the unusual dorsal location as the Air Force had required the carriage of an underbelly semi-conformal nuclear weapon. The intake also severely limited rear visibility. Nonetheless this was not considered very important for a tactical fighter-bomber aircraft at that time, and furthermore it was assumed that air combat would be via guided missile exchanges outside visual range.

A two-seat version of the F-107 was proposed by North American, which seated both crewmembers under a single canopy in an extended forward fuselage, but none were built.

In August 1954, a contract was signed for three prototypes along with a pre-production order for six additional airframes.

General characteristics

Crew: one
Length: 61 ft 10 in (18.85 m)
Wingspan: 36 ft 7 in (11.15 m)
Height: 19 ft 8 in (5.89 m)
Wing area: 376 sq ft (35 m2)
Empty weight: 22,696 lb (10,295 kg)
Gross weight: 39,755 lb (18,033 kg)
Max takeoff weight: 41,537 lb (18,841 kg)
Powerplant: 1 × Pratt & Whitney YJ75-P-9 turbojet, 24,500 lbf (109 kN) thrust
Performance

Maximum speed: 1,295 mph (2,084 km/h, 1,125 kn)
Maximum speed: Mach 2
Range: 2,428 mi (3,885 km, 2,109 nmi)
Service ceiling: 53,200 ft (16,220 m)
Rate of climb: 39,900 ft/min (203 m/s)
Wing loading: 106 lb/sq ft (516 kg/m2)
Thrust/weight: 0.62
Armament
Guns: 4x 20 mm Pontiac M39 cannon OR 1x 20 mm, 6 barrel M61 Vulcan autocannon
Bombs: 10,000 lb (4,500 kg) on 5 hardpoints; 2 under each wing, 1 semi-recessed ordnance station under fuselage centerline. Wide variety of ordnance, including tactical nuclear weapons

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