The Caudron C.74 was a ten-seat, four engine passenger

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

built in

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

in 1922. It showed promise but the sole prototype crashed fatally in a competition and no more were completed.

Design and development

The C.74 was a large biplane, powered by four

Hispano-Suiza 8F The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza 8A ...

b water-cooled, upright

V-8 engine A V8 engine is an eight-cylinder piston engine in which two banks of four cylinders share a common crankshaft and are arranged in a V configuration. The first V8 engine was produced by the French Antoinette company in 1904, developed and u ...

s mounted in two pairs, each pair with one engine in

tractor configuration In aviation, the term tractor configuration refers to an aircraft constructed in the standard configuration with its engine mounted with the propeller in front of it so that the aircraft is "pulled" through the air. Oppositely, the pusher c ...

and the other as a pusher. It was built from wood and steel and covered in

plywood Plywood is a material manufactured from thin layers or "plies" of wood veneer that are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. It is an engineered wood from the family of manufactured ...

and

fabric Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...

. An enclosed cabin could accommodate ten passengers. The C.74 had rectangular plan wings, with the upper plane slightly greater in span than the lower. It was a three bay biplane without stagger, with two sets of parallel, vertical

interplane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...

s outboard and two sets of leaning parallel struts inboard on each wing. The latter met on the lower wing but diverged upwards in a narrow V, forming a cradle for an engine pair.

Cabane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...

s joined the wing centre section to the upper fuselage longerons. The airliner had a flat sided

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 aircraft t ...

with two open

cockpit A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a Pilot in command, pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the ...

s in

tandem Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction. The original use of the term in English was in ''tandem harness'', which is used for two ...

for the crew, one ahead of the wing

leading edge The leading edge of an airfoil surface such as a wing is its foremost edge and is therefore the part which first meets the oncoming air.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, ...

and the other close behind but under the wing. The cabin had five flat side windows, arranged in a group of three in front of the cockpits and two behind, plus a curved window in the cylindrical nose. Aft of the last window was a port side cabin entry door. At the rear, the C.74's

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 ...

was triangular and broad, carrying a vertically edged balanced rudder that reached down to the keel. The

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 gyroplane ...

was mounted on top of the fuselage and the

elevator An elevator or lift is a wire rope, cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or deck (building), decks of a building, watercraft, ...

s required a cut-out for rudder movement. Its

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 ...

was essentially of the

tailskid Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Term ...

type. On each side, vertical V-form legs from the lower fuselage longerons and from under the meeting points of the two engine support struts carried a single axle with a mainwheel at either end. In addition, a third axle, similarly mounted from the fuselage but forward of the wing, carried a pair of slightly smaller wheels intended to prevent nose-overs. On each lower wing a pair of backward trailing thin skids, attached below each of the two rear outboard interplane struts and lightly braced from the

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

extended well behind, giving protection against accidental ground contact. The C.74 was first flown in 1922 and seemed likely to sell well. Entered into ''Le Grand Prix des Avions des Transports'' (The Great Prize for Transport Aircraft) competition held in early November 1922, it was well regarded by the jury. On 14 November, as it took off from

Le Bourget Le Bourget () is a commune in the northeastern suburbs of Paris, France. It is located from the center of Paris. The commune features Le Bourget Airport, which in turn hosts the Musée de l'Air et de l'Espace (Air and Space Museum). A very ...

, bolts securing one of the

propeller A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

s failed and the C.74 crashed killing all three crew members, the pilot Alphonse Poirée and mechanics Courcy and Bovillier. No more were built.

Specifications

References

{{Caudron aircraft C.077 1920s French airliners Four-engined push-pull aircraft Biplanes