The Bernard SIMB AB 12 was a French single engine, single-seat

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 ...

fighter aircraft built in the 1920s. Though advanced for its time, it failed to gain a production order and only one was built.

Design and development

Like the

Bernard SIMB AB 10 The Bernard SIMB AB 10 was a French single-engine, single-seat, highly streamlined, cantilever, all-metal low-wing monoplane of advanced design. It first flew in 1924 but was not ordered into production. Design and development The Bernard SIMB ...

, the AB 12 was an all-metal, single-seat, monoplane fighter 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 cant ...

wing. It differed from the AB10 in having a

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 ...

, a more conventional undercarriage and four machine guns. The wing plans of both aircraft were similar, straight tapered with squared tips, though the AB 12 had a span greater. The

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

of both designs was also similar: the AB 12 had a

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 gyroplan ...

with swept

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, ...

s and separate

elevators 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 ...

mounted on top of the

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 ...

and a wide

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 ( ...

, almost straight edged

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 ...

, though its

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 adverse yaw a ...

, moving between the elevators, ended on the upper fuselage line. The fuselage had an oval cross section with the open cockpit over the wing, a short, faired headrest behind it. The AB 12 was powered by a

Gnome-Rhône 9Ab The Bristol Jupiter was a British nine-cylinder single-row piston radial engine built by the Bristol Aeroplane Company. Originally designed late in World War I and known as the Cosmos Jupiter, a lengthy series of upgrades and developments turn ...

radial, a

licence-built Licensed production is the production under license of technology developed elsewhere. The licensee provides the licensor of a specific product with legal production rights, technical information, process technology, and any other proprietary compon ...

Bristol Jupiter. By the standards of the day this was quite well cowled-in for a radial but the cylinder heads protruded for cooling. The details of the gun mounting are not clear, but images show at least one on the starboard side firing through a slot in the nose just above mid-height, the opening extending between two cylinders. The undercarriage of the AB 12 was quite conventional and very different from that of the AB 10. It had a pair of single mainwheels mounted on a single, faired axle, with V-form legs attached to the lower fuselage. The

tricycle gear Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', arranged in a tricycle fashion. The tricycle arrangement has a single nose wheel in the front, and two or more main wheels slightly aft of the center of gravity. Tricycle g ...

was completed by a tailskid. Overall, the AB 12 was 40% more powerful but less aerodynamically clean and 7% heavier than the AB 10, so its maximum speed was only 6% higher. Monoplanes in a biplane era, neither design received a production order and only one of each was built.

Design and development

Specifications

References

Bibliography

External links