The Burnelli UB-14, also known as the Cunliffe-Owen Clyde Clipper, was a 1930s American prototype lifting-fuselage airliner designed and built by

Vincent Burnelli Vincent Justus Burnelli (November 22, 1895 – June 22, 1964) was an American aeronautics engineer, instrumental in furthering the lifting body and flying wing concept. Biography Burnelli was born on November 22, 1895, in Temple, Texas. ...

Design and development

Following on from his earlier designs

designed a commercial transport version using the lifting-fuselage concept. Burnelli's designs were based on the idea that an airfoil-section fuselage would contribute to the lift generated. The Burnelli UB-14 first flew in

1934 Events January–February * January 1 – The International Telecommunication Union, a specialist agency of the League of Nations, is established. * January 15 – The 8.0 Nepal–Bihar earthquake strikes Nepal and Bihar with a maxi ...

, the airfoil-section

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraf ...

was the centre-section of the wing. The aircraft had twin tailbooms and a widespan

tailplane A tailplane, also known as a horizontal stabiliser, is a small lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters and gyropla ...

and

elevator An elevator or lift is a cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or decks of a building, vessel, or other structure. They a ...

fitted with twin

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...

s and

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adve ...

s. The UB-14 had retractable

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for takeoff or landing. For aircraft it is generally needed for both. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin ...

and was powered by two Pratt & Whitney

radial engine The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is ...

s. An enclosed cockpit for the crew of two was located on the centre wing's upper surface. The cabin held 14 to 18 passengers.

Operational history

The first prototype, UB-14, was destroyed in a 1935 accident attributed to faulty maintenance on the aileron control system. Burnelli then designed and built an improved version, the UB-14B. A modified version of the UB-14B design was built under licence in the United Kingdom by Cunliffe-Owen Aircraft, powered by two Bristol Perseus XIVC radials as the Cunliffe-Owen OA-1. A contemporary photo shows the mockup of the original UB-14B, to be built by

Scottish Aviation Scottish Aviation Limited was an aircraft manufacturer based at Prestwick, Scotland. History The company was founded in 1935. Originally a flying school operator, the company took on maintenance work in 1938. During the Second World War, Scott ...

before bankruptcy. This design was to have had streamline inline engines. The OA-1 used radial engines. In September 1936, Burnelli applied to the CAA for approval to fly a transatlantic flight with Clyde Edward Pangborn as the selected pilot. CunliffeOOA1

The Cunliffe-Owen failed its airworthiness certification due to excessive takeoff run and poor workmanship. It was performance tested at the A&AEE Boscombe Down in 1939. After appropriate work, in June 1941

Jim Mollison James Allan Mollison MBE (19 April 1905 – 30 October 1959) was a Scottish pioneer aviator who, flying solo or with his wife, Amy Johnson, set many records during the rapid development of aviation in the 1930s. Early years Born on 19 ...

and an

Air Transport Auxiliary The Air Transport Auxiliary (ATA) was a British civilian organisation set up at the start of the Second World War with headquarters at White Waltham Airfield in Berkshire. The ATA ferried new, repaired and damaged military aircraft between factori ...

crew delivered Cunliffe-Owen OA-1 G-AFMB to

Fort Lamy N'Djamena ( ) is the capital and largest city of Chad. It is also a special statute region, divided into 10 districts or ''arrondissements''. The city serves as the centre of economic activity in Chad. Meat, fish and cotton processing are th ...

, Chad. The aircraft was fitted out as a personal transport for General De Gaulle. It was later abandoned at RAF Kabrit in

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Medit ...

, and burned during VJ-Day celebrations. The one other aircraft landed in

Vichy France Vichy France (french: Régime de Vichy; 10 July 1940 – 9 August 1944), officially the French State ('), was the fascist French state headed by Marshal Philippe Pétain during World War II. Officially independent, but with half of its te ...

en route to Fort Lamy

Variants

* UB-14 Prototype, powered by Pratt & Whitney engines. Built by Burnelli Company. Destroyed 13 January 1935, without injury to those aboard. * UB-14B Second prototype with modifications. Built by Burnelli Company. * UB-14B Third prototype, modified from second unit. Built by Cunliffe Owen Aircraft in United Kingdom.

Specifications (UB-14B)

Burnelli_UB-14_3-view_L'Aerophile_February_1936

Airfoils: * Fuselage: NACA 4323 * Exterior wing, root: NACA 2412 * Exterior wing, tip: NACA 2409 Flight magazine, 1936 / pg. 1591

References

Notes

Bibliography

* ''The Illustrated Encyclopedia of Aircraft (Part Work 1982–1985)''. London: Orbis Publishing, 1986. * Mason, Tim. ''The Secret Years: Flight Testing at Boscombe Down, 1939–1945''. Crowborough, UK: Hikoki Publications, 2010. .

External links

Photographs of the Burnelli UB-14
{{Burnelli aircraft UB-14 1930s United States airliners Lifting bodies High-wing aircraft Aircraft first flown in 1934 Twin piston-engined tractor aircraft Cunliffe-Owen aircraft