The Duverne-Saran 01 was a twin engine, three seat touring aircraft 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 the mid-1930s. Only one was completed.

Design

The Duverne-Saran 01 was designed to carry a pilot and two passengers rapidly but economically with the extra security provided by two engines. It was a wooden aircraft with a

low Low or LOW or lows, may refer to: People * Low (surname), listing people surnamed Low Places * Low, Quebec, Canada * Low, Utah, United States * Lo Wu station (MTR code LOW), Hong Kong; a rail station * Salzburg Airport (ICAO airport code: LO ...

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...

wing set with about 6° of dihedral. The wing was in three parts, with a short span, constant

chord Chord may refer to: * Chord (music), an aggregate of musical pitches sounded simultaneously ** Guitar chord a chord played on a guitar, which has a particular tuning * Chord (geometry), a line segment joining two points on a curve * Chord ( ...

centre section and two straight-tapered, square-tipped outer panels. Long ailerons on the outer panels occupied about 60% of the span. There were split flaps on either side of the ailerons. Structurally the wings had a box spar, shaping the section and

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 ...

covered; the section aft of the box was formed by

rib In vertebrate anatomy, ribs ( la, costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the ches ...

s and was fabric covered. The Duverne-Saran 01's engines were mounted from the wing at the junctions between the centre section and outer panels. The Chaise 4-E engines were air-cooled, inverted V-4s with a narrow angle between the cylinders, so were unusually compact. The propeller shafts were at wing level, with the bulk of the engine and

cowling A cowling is the removable covering of a vehicle's engine, most often found on automobiles, motorcycles, airplanes, and on outboard boat motors. On airplanes, cowlings are used to reduce drag and to cool the engine. On boats, cowlings are a cove ...

s ahead and below the wing. Its

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 ...

was built around four spruce

longerons In engineering, a longeron and stringer is the load-bearing component of a framework. The term is commonly used in connection with aircraft fuselages and automobile chassis. Longerons are used in conjunction with stringers to form structural ...

and was rectangular in section. The extreme nose was a

duralumin Duralumin (also called duraluminum, duraluminium, duralum, dural(l)ium, or dural) is a trade name for one of the earliest types of age-hardenable aluminium alloys. The term is a combination of '' Dürener'' and ''aluminium''. Its use as a tra ...

dome, the central region was ply covered and fabric covered the tapering rear section. Its three seats were in tandem, with the pilot in front over 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, ...

, a passenger behind over the

centre of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may ...

and a third seat, which could be fitted with dual control, in the rear. A windowed cabin top was envisaged but does not appear in the few published photographs of the Duverne-Saran, so it may not have been fitted. The fuselage design made it easy to modify; for example, a hinged panel in the side could admit patients on a stretcher. The tail was conventional with a trapezoidal

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 ...

mounted on the upper fuselage carrying rectangular

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. The angle of incidence of the tailplane could be adjusted in flight for trim but the elevators were not

balanced In telecommunications and professional audio, a balanced line or balanced signal pair is a circuit consisting of two conductors of the same type, both of which have equal impedances along their lengths and equal impedances to ground and to other ...

. The Duverne-Saran had a 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 ...

and rectangular

balanced rudder Balanced rudders are used by both ships and aircraft. Both may indicate a portion of the rudder surface ahead of the hinge, placed to lower the control loads needed to turn the rudder. For aircraft the method can also be applied to elevators and ...

. It had a fixed 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 ...

with mainwheels on faired half-axles from the bottom of the fuselage, with short, faired, rubber ring

shock absorber A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most sh ...

s from the outer lower engine mounts.

Development

The Duverne-Saran 01, prototype and only example of the type, flew for the first time on 23 April 1935. It was one of sixteen prototypes that took part in a , ten-day tour around France which started at

Orly Orly () is a commune in the southern suburbs of Paris, Île-de-France. It is located from the center of Paris. The name of Orly came from Latin ''Aureliacum'', "the villa of Aurelius". Orly Airport partially lies on the territory of the comm ...

on 18 October 1935. On 28 April 1936 it arrived at Villacoublay for its official trials. At that time it still had the Chaise engines but by March 1937 these had been replaced with Train 6T

straight six The straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine balan ...

cylinder, inverted, air-cooled engines. It first flew with these early in May 1937 and trials continued until at least October. In December 1937 it changed engines again, with the installation of smaller,

Train 4T The Train 2T, 4T and 6T were low power piston engines for light aircraft, produced in France. They were inverted, air-cooled in-line engines with the same bore and stroke, differing chiefly in the number of cylinders. Design and development In ...

s, similar to the 6Ts but with four cylinders, in order to make record attempts in the low power category. A year later, in December 1938 the Duverne-Saran had begun tests powered by two air-cooled inié 4.D0 Horus flat fours.

Specifications (Chaise engine)

References

{{reflist, 2, refs= {{cite book, title= L'Année Aeronautique 1933-34 , last=Hirschauer, first=L. , last2=Dolfus , first2=Ch., year=1933, publisher=Dunod, location=Paris, page=60-61, url=http://gallica.bnf.fr/ark:/12148/bpt6k65535273/f65 {{cite journal , date=4 March 1935, title=Le bimoteur léger Duverne-Saran, journal=Les Ailes, first=André, last=Frachet, issue=745, pages=3, url=http://gallica.bnf.fr/ark:/12148/bpt6k6553900t/f3 {{cite journal , date=11 March 1937, title=Les Avions de Tourisme, journal=Les Ailes, issue=821, pages=4, url=http://gallica.bnf.fr/ark:/12148/bpt6k6560492p/f4 {{cite journal , date=13 May 1937, title=Les avions d'essais, journal=Les Ailes, issue=830, pages=11, url=http://gallica.bnf.fr/ark:/12148/bpt6k65605016/f11 {{cite journal , date=21 October 1937, title=Les avions prives, journal=Les Ailes, issue=853, pages=15, url=http://gallica.bnf.fr/ark:/12148/bpt6k65605246/f15 {{cite journal , date=30 December 1937, title=Les avions prives, journal=Les Ailes, issue=863, pages=15, url=http://gallica.bnf.fr/ark:/12148/bpt6k6560534k/f15 {{cite journal , date=30 December 1937, title=Les avions legers, journal=Les Ailes, issue=913, pages=10, url= http://gallica.bnf.fr/ark:/12148/bpt6k65559206/f9 {{cite journal , date=18 October 1935, title=Essais, raíds et records d'aviation, journal=Le Journal , pages=3, url=http://gallica.bnf.fr/ark:/12148/bpt6k76339229/f11 {{cite journal , date=8 May 1936, title=Les essais en vol, journal=l'Aéro , pages=5, url=http://gallica.bnf.fr/ark:/12148/bpt6k57130798/f5 {{cite web , url=https://www.aviafrance.com/duverne-saran-aviation-france-10256.htm, title=Duverne-Saran , author=Bruno Parmentier , date=17 January 2013 , accessdate=28 March 2016 {{cite web , url=http://www.enginehistory.org/HOAE/Minie.html, title=Outstanding Compilation of Horizontally Opposed Aero Engine Information , author=Jack Erickson , accessdate=30 March 2016 1930s French sport aircraft Low-wing aircraft Aircraft first flown in 1935 Twin piston-engined tractor aircraft