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, based on the F-100 Super Sabre. It incorporated many innovations and radical design features, notably the over-fuselage air intakes. The competition was eventually won by the Republic F-105 Thunderchief, and two of the three 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.

F-107
General information
TypeFighter-bomber
National originUnited States
ManufacturerNorth American Aviation
StatusCanceled
Primary usersUnited States Air Force
Number built3
History
First flight10 September 1956
Retired25 November 1957
Developed fromNorth American F-100 Super Sabre

Design and development

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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.[1] 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 refueling capability was provided while a retractable tailskid was installed.[2] An all-moving vertical fin and an automated flight control system were incorporated which permitted the aircraft to roll at supersonic speeds using spoilers.[3] The flight control system was upgraded by the addition of pitch and yaw dampers.[2]

 
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.[4] 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.[5] 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.[6]

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.[7]

 
The first F-107A 55-5118 with its vertically sliding canopy in open position.

In an emergency, the ejection seat was designed to blast directly through the non-jettisoning canopy and bring the pilot swiftly clear of the air intakes. In non-emergency operation, the canopy opened by sliding vertically upwards via guide mechanism, rather than the typical arrangement of a hinged or horizontally sliding canopy.[8]

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.[9]

In August 1954, a contract was signed for three prototypes along with a pre-production order for six additional airframes.[5]

Designation and names

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Extensive design changes resulted in its redesignation from F-100B to F-107A before the first prototype flew. The F-107 was never given an official name, but was sometimes informally called the "Super Super Sabre"[10] referring to North American's earlier fighter design, the F-100 Super Sabre.[11] The designation "F-107A" was the only one assigned to the aircraft,[11][12] though "YF-107A" is often used in publications.[2][13] The aircraft is also informally called the "Ultra Sabre".[14]

Operational history

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North American F-107A #1 55-5118

The first F-107A (serial number 55-5118) with North American's chief test pilot Bob Baker at the controls, made its initial flight on 10 September 1956, attaining Mach 1.03.[15] After the successful test flight, the brakechute did not deploy, which resulted in a "hot" landing with the nose gear strut breaking.[15] The aircraft first achieved Mach 2 in tests on 3 November 1956.

It was joined by the second F-107A (55-5119), which made its first flight on 28 November 1956. It was used for weapons testing with both conventional and atomic bombs.[16] The last prototype, (55-5120) had its maiden flight on 10 December 1956. At the conclusion of the F-107A's successful test program, the Tactical Air Command decided to hold a fly-off competition between the F-107A and the Republic F-105 which was designed to same mission requirements and used the same engine. Although the competition was close, the F-105 was selected as the new standard TAC tactical fighter. The three F-107A prototypes were relegated to test flying and the pre-production order was cancelled.[17]

In late 1957, prototypes #1 (55-5118) and #3 (55-5120) were leased to the National Advisory Committee for Aeronautics (NACA) for high-speed flight research. Aircraft #1 is now in the collection of the Pima Air & Space Museum. In September 1959, with Scott Crossfield at the controls, aircraft #3 was damaged during an aborted takeoff. The aircraft was not repaired and, ultimately, used for fire fighting training and was destroyed in the early 1960s.[18] (55-5120 was also noted to be stored in poor condition in the Tallmantz collection at Orange County Airport California in September 1970.)[citation needed]

Prototype #2 (55-5119) was not used by NACA and flown on 25 November 1957 to the National Museum of the United States Air Force at Wright-Patterson Air Force Base near Dayton, Ohio.[19]

Variants

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NA-212
North American design or charge number.
F-100B
Original military designation for the NA-212, not used
F-107A
Military designation for nine prototype NA-212s ordered, only three built.

Aircraft on display

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Specifications (F-107A)

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Data from Simone and Pace.[21][22]

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

See also

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Related development

Aircraft of comparable role, configuration, and era

Related lists

References

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Citations

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  1. ^ Pace 1986, p. 39.
  2. ^ a b c Baugher, Joe. "North American F-100B/F-107." USAF Fighters, 27 November 1999. Retrieved: 10 July 2011.
  3. ^ Simone 2002, pp. 25–30.
  4. ^ Simone 2002, pp. 32–35.
  5. ^ a b Jones 1975, p. 268.
  6. ^ Simone 2002, p. 35.
  7. ^ Pace 1986, pp. 24, 26, 30.
  8. ^ "Was This Strange Jet the Best Fighter the U.S. Air Force Never Bought?". HistoryNet. 2021-04-21. Retrieved 2023-05-10.
  9. ^ Jenkins/Landis 1975, p. 178.
  10. ^ Pace 1986, p. 42.
  11. ^ a b Simone 2002, p. 2.
  12. ^ "Designation-Systems.net Original USAF MDS Document" (PDF).
  13. ^ Donald 2003, p. 23.
  14. ^ Weeks, John A. III. "YF-107A — The Ultra Sabre Survivors." Aviation History And Aircraft Photography, 2009. Retrieved: 31 March 2009.
  15. ^ a b Angelucci and Bowers 1987, p. 356.
  16. ^ Pace 1986, pp. 24, 26.
  17. ^ Pace 1986, p. 33.
  18. ^ Simone 2002, p. 127.
  19. ^ a b "NORTH AMERICAN F-107A" National Museum of the USAF. Retrieved: 16 July 2017.
  20. ^ "YF-107A Ultra Sabre/55-5118." Archived 2013-01-07 at the Wayback Machine Pima Air and Space Museum. Retrieved: 10 May 2013.
  21. ^ Simone 2002, pp. 128–129.
  22. ^ Pace 2016, pp. 203–207. The Big Book of X-Bombers and X-fighters: USAF Jet-Powered Experimental Aircraft and their Propulsion Systems. ISBN 978-0-7603-4950-2

Bibliography

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  • Angelucci, Enzo and Peter Bowers. The American Fighter: the Definite Guide to American Fighter Aircraft from 1917 to the Present. New York: Orion Books, 1987. ISBN 0-517-56588-9.
  • Donald, David, ed. Century Jets. Norwalk, Connecticut, USA: AIRtime Publishing, 2003. ISBN 1-880588-68-4.
  • "F-107A: The Ultimate Sabre DVD." Georgetown, Texas: Flightline rocket.aero, 2005.
  • Jenkins, Dennis R. and Tony R. Landis. Experimental & Prototype U.S. Air Force Jet Fighters. North Branch, Minnesota, USA: Specialty Press, 2008. ISBN 978-1-58007-111-6.
  • Jones, Lloyd S. U.S. Fighters: Army Air-Force 1925 to 1980s. Fallbrook, California: Aero Publishers, Inc., 1975. ISBN 0-8168-9201-6.
  • Knaack, Marcelle Size. Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1 Post-World War II Fighters 1945–1973. Washington, DC: Office of Air Force History, 1978. ISBN 0-912799-59-5.
  • Pace, Steve. "Supersonic Cavaliers." Airpower, Volume 16, no. 6, November 1986.
  • Simone, William J. North American F-107A. Simi Valley, California: Ginter Publishing, 2002. ISBN 0-942612-98-1.
  • United States Air Force Museum Guidebook. Wright-Patterson AFC, Ohio: Air Force Association, 1975 edition.
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