Overview
This entry covers gallery images that appear to show patent drawings of flying-wing aircraft — technical illustrations from patent applications depicting various flying-wing aircraft designs. Patent drawings are formal technical illustrations submitted with patent applications to describe the invention. The images' specific source, date, and provenance cannot be verified from the images alone.
The flying-wing configuration — in which the aircraft has no distinct fuselage or tail, and the payload, crew, and engines are housed within the wing — has been the subject of numerous patents since the early 20th century. The most significant flying-wing patents were filed by Jack Northrop in the 1940s, and these patents established the conceptual foundation for the B-2 Spirit stealth bomber, which was developed decades later.
The Flying-Wing Concept
The flying wing is an aircraft configuration in which the aircraft consists of a single wing, with no distinct fuselage or tail. All payload, crew, fuel, and engines are housed within the wing. The flying wing offers several theoretical advantages:
- Minimum drag: The flying wing has the minimum possible wetted area (surface area) for a given lift, because there is no fuselage or tail to add surface area. This reduces skin-friction drag and improves fuel efficiency.
- Maximum lift efficiency: The entire aircraft generates lift, unlike a conventional aircraft where only the wings generate significant lift.
- Large internal volume: The thick wing centre section provides ample internal volume for fuel, payload, and systems.
However, the flying wing also presents significant challenges:
- Stability and control: Without a tail, the flying wing lacks natural pitch stability and directional stability. Early flying wings were difficult to control, and the configuration only became practical with the development of fly-by-wire flight control systems.
- Centre of gravity management: The flying wing's centre of gravity must be carefully managed, as the aircraft has limited ability to compensate for centre of gravity shifts.
- Payload accommodation: The thin outer wings cannot accommodate payload, so all payload must be in the thick centre section.
Jack Northrop's Pioneering Work
John Knudsen "Jack" Northrop was the most persistent and influential advocate of the flying-wing configuration. Northrop believed that the flying wing was the ideal aircraft configuration and devoted much of his career to developing it.
Northrop's flying-wing programmes included:
- N-1M (1940): A small flying-wing demonstrator, the first Northrop flying wing to fly.
- N-9M (1942): A 1/3-scale piloted test aircraft for the XB-35 programme. Four N-9M aircraft were built.
- XB-35 (1946): A full-scale flying-wing bomber prototype, powered by pusher propellers. The XB-35 first flew on 25 June 1946.
- YB-35 (1948): Production prototype of the XB-35.
- YB-49 (1947): A jet-powered variant of the YB-35, with eight jet engines replacing the propellers. The YB-49 first flew on 21 October 1947.
The YB-49 was the most capable of Northrop's flying wings, but it was not selected for production. The Air Force chose the conventional Convair B-36 Peacemaker instead, citing the YB-49's stability and control problems and limited range. The YB-49 programme was cancelled in 1949, and Jack Northrop was reportedly devastated by the decision.
Northrop filed several patents on flying-wing aircraft designs during this period, covering the planform, control system, and structural concepts. These patents established the intellectual property foundation for the flying-wing configuration.
The N-9M, YB-35, and YB-49
The N-9M was a 1/3-scale piloted test aircraft built to validate the design of the XB-35 flying-wing bomber. Four N-9M aircraft were built (N-9M-A, N-9M-B, N-9M-C, and N-9M-D), and they were used to test the aerodynamic and handling characteristics of the flying-wing configuration. The N-9M aircraft were powered by two pusher propellers driven by inline engines.
The XB-35 was a full-scale flying-wing bomber with a wingspan of 172 feet (52.4 m) — the same as the later B-2 Spirit. The XB-35 was powered by four Pratt & Whitney R-4360 Wasp Major radial engines driving pusher propellers. The XB-35 first flew on 25 June 1946, but the programme was plagued by technical problems, particularly with the propeller gearboxes and the flight control system.
The YB-49 was a jet-powered variant of the YB-35, with eight Allison J35 turbojets replacing the propeller engines. The YB-49 first flew on 21 October 1947 and demonstrated significantly better performance than the propeller-powered YB-35. However, the YB-49 still suffered from stability and control problems, and the Air Force was not confident in the aircraft's suitability for operational service.
The YB-49 programme was cancelled in 1949. One YB-49 was destroyed in a crash on 5 June 1948, killing its crew of five (including Captain Glenn Edwards, for whom Edwards Air Force Base is named).
Patent History and the B-2 Spirit
Jack Northrop's flying-wing patents, filed in the 1940s, established the conceptual foundation for the B-2 Spirit stealth bomber, which was developed in the 1980s — four decades after Northrop's original work. The B-2's planform is remarkably similar to the YB-49's, and the B-2's development team referenced Northrop's patents and design studies during the B-2 design process.
Jack Northrop, by then elderly and in failing health, was reportedly shown a model of the B-2 Spirit shortly before his death in 1981. According to accounts, Northrop said, "Now I know why God has kept me alive for 25 years." The B-2's development vindicated Northrop's lifelong belief in the flying-wing configuration.
The B-2 Spirit, which entered service in 1997, is the only operational flying-wing bomber in the world. Its success has validated the flying-wing concept and inspired further development, including the B-21 Raider (currently under development by Northrop Grumman) and numerous unmanned flying-wing aircraft.
Declassification and Provenance
The gallery images are patent-style drawings from a legacy compilation whose CIA-P2 catalog numbers are legacy identifiers and do not establish CIA authorship, declassification, or provenance. The images depict patent-style technical drawings, not operational hardware, and should not be interpreted as evidence of CIA involvement in flying-wing development.
The images may originate from public patent filings, historical archives, or technical publications. Without verified provenance, the images should be treated as historical technical drawings of unknown origin.
References
- US Patent and Trademark Office. Northrop flying-wing patents (various, 1940s).
- Pape, G.R. and Baldwin, J.W. Northrop Flying Wings. Schiffer Publishing.
- Coleman, Ted. Jack Northrop and the Flying Wing. W.W. Norton.
- Crickmore, Paul. Northrop B-2 Spirit. Osprey Publishing.
- National Air and Space Museum. "Northrop N-9M" and "Northrop YB-49." Smithsonian Institution.