The Buscaylet-de Monge 7-4 was a small, French,

twin-boom A twin-boom aircraft is characterised by two longitudinal booms (extended nacelle-like bodies). The booms may contain ancillary items such as fuel tanks and/or provide a supporting structure for other items. Typically, twin tailbooms support ...

aircraft without a

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 ...

, built in the mid-1920s to explore the characteristics of a proposed larger machine.

Design and development

The de Monge 7-4 was designed and built to provide aerodynamic information on the three times larger proposed de Monge 72. Each was a twin boom

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

with a conventional empennage but no

. Instead, the wing between the booms was extended in chord and greatly thickened to provide depth for

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. The smaller aircraft had two engines, mounted just within the booms; the de Monge 72 was to have had a third engine on the central 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, ...

. It was designed by Belgian pioneer

Louis de Monge Louis de Monge (Vicomte Pierre Louis de Monge de Franeau) (1890–New York, 25 July 1977) was a notable Belgian engineer. He is mainly remembered as the designer of the Bugatti Model 100 racing aircraft. Career He was interested in aircraft from h ...

. Both the inner and outer sections of the wing were built around two wooden box spars and wooden ribs. The final ribs of the centre-section extended rearwards to the tail as the booms and the outer panels were bolted to them. An open single cockpit for pilot and passenger in side-by-side seats was positioned between the spars. In plan the centre-section was rectangular, about in span, in chord (more than half the overall length of the aircraft) and was thick. The outer panels were braced to the lower centre-section outer edge on each side with two steel tube struts. In plan the outer panels were strongly tapering

trapezoid A quadrilateral with at least one pair of parallel sides is called a trapezoid () in American and Canadian English. In British and other forms of English, it is called a trapezium (). A trapezoid is necessarily a Convex polygon, convex quadri ...

s, carrying

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

s along the entire

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. ...

. The de Monge 7-4 was powered by two

Anzani Anzani was an engine manufacturer founded by the Italian Alessandro Anzani (1877–1956), which produced proprietary engines for aircraft, cars, boats, and motorcycles in factories in Britain, France and Italy. Overview From his native Italy, An ...

air-cooled 3-cylinder

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 ca ...

s on a girder across the

of the centre-section. Since they were both just within the centre-section span, they were less than apart and 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 ...

disks slightly overlapped; to avoid damage both engines were slightly canted to starboard. The top of the rear ends of the booms were bridged by a near-rectangular plan horizontal tail with a full span

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, ...

. This had a pair of cut-outs for the deep

rudders 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 adverse ya ...

, mounted on near triangular

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; there was another, rudderless fin mounted at the centre of 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 ...

. The de Monge 7-4 had a conventional fixed, split-axle, tailskid

undercarriage Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include: *The landing gear of an aircraft. *The ch ...

. The axles were hinged from a V-strut, mounted on the centreline and braced with transverse wires, with their outer ends mounted on near-vertical rubber shock absorbing struts and hinged, trailing struts, both to the lower centre-section outer edge. Each boom carried a small tailskid. The exact date of the first flight of the de Monge 7-4 is not known but it was present for the 1923 Coupe de Zenith, piloted by one Brusseaux. However, for unrecorded reasons it failed to depart on the first stage. Its early trials had been flown by Alexis Maneyrol, who was flying a Peyret aircraft at this competition. It competed in the same contest in 1924 but once again was forced to retire. By this time more powerful Anzani engines had been fitted.

Specifications

References

{{reflist, refs= {{cite book , title=L'anée d'Aviation 1923-1924, last=Hirschauer , first=L. , first2=Ch. , last2=Dollfus , year=1924, publisher= Dunod, location=Paris , url=http://gallica.bnf.fr/ark:/12148/bpt6k65556487/f114 {{cite journal , date=20 December 1923 , title= The de Monge Light Monoplane, journal=

Flight Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can be a ...

, volume=XV , issue=50 , pages=762–3 , url= https://www.flightglobal.com/pdfarchive/view/1923/1923%20-%200762.html , archive-url = https://web.archive.org/web/20171015203233/https://www.flightglobal.com/pdfarchive/view/1923/1923%20-%200762.html , archive-date = 15 October 2017, access-date=4 January 2022 {{cite journal , date=October 1923 , title=Le bimoteur léger Buscaylet-de Monge 7-4, journal=L'Aéronautique, volume=5 , issue=53 , pages=44, url= http://gallica.bnf.fr/ark:/12148/bpt6k65555677/f43 {{cite journal , date=1–15 July 1924 , title=La Coupe Zénith de consommation, journal=L'Aérophile , issue=13-14 , pages=217, url= http://gallica.bnf.fr/ark:/12148/bpt6k6554816n/f223 Twin-boom aircraft 1920s French experimental aircraft Aircraft first flown in 1923 Twin-engined tractor aircraft