The Macfie Monoplane was a British

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 shoulder wing, tractor

Tractor configuration

thumb|right|[[Evektor-Aerotechnik|Aerotechnik EV97A Eurostar]], a tractor configuration aircraft, being pulled into position by its pilot for refuelling....

 monoplane

Monoplane

A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...

. The aircraft was powered by a 35 hp (26 kW) J.A.P. V8 engine

V8 engine

A V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....

 fixed at the front of an open-frame 'fuselage

Fuselage

The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...

', at the rear end of which a tailplane

Tailplane

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

 and vertical rudder

Rudder

A rudder is a device used to steer a ship, boat, submarine, hovercraft, aircraft or other conveyance that moves through a medium . On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane...

 were mounted.

The Monoplane was designed, built and flown by Robert Francis Macfie who later, as a member of the 1915 British Landships Committee

Landships Committee

The Landships Committee was a small British war cabinet committee established in February 1915 to deal with the design and construction of what would turn out to be tanks during the First World War...

, made a significant contribution to the development of the armoured landship

Landship

A landship is a large vehicle that travels on land, as opposed to on water, air, or in space. Because of their large size, their use on land is seen as impractical due to terrain obstacles, and soft ground that cannot support such large weight. Such problems are non-existent on water and in space...

 or tank

Tank

A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility, tactical offensive, and defensive capabilities...

.

The aircraft superficially resembled the Blériot XI

Blériot XI

The Blériot XI is the aircraft in which, on 25 July 1909, Louis Blériot made the first flight across the English Channel made in a heavier-than-air aircraft . This achievement is one of the most famous accomplishments of the early years of aviation, and not only won Blériot a lasting place in...

 in terms of overall configuration but was in almost every design detail different from this aircraft. Like on the Blériot, control was effected using wing-warping via wires attached to king posts. However the Macfie monoplane incorporated many innovative features and in particular was designed for ease of construction, maintenance and repair.

Fuselage

The body of the Macfie monoplane comprised a uncovered V-section framework made of ash wood

Ash tree

Fraxinus is a genus flowering plants in the olive and lilac family, Oleaceae. It contains 45-65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The tree's common English name, ash, goes back to the Old English æsc, while the generic name...

, in which three longitudinal members were braced together at intervals of approximately 2 ft. (0.61 m) by wooden struts. The framework was approximately 3 ft. (0.91 m) in height at the forward end, tapering to 1 ft. (0.30 m) at the tail; likewise the width of the frame tapered from approx. 2 ft. 6 in. (0.76 m) at the front to 1 ft at the tail. The lowest longitudinal member, at the point of the V-section, was approximately parallel to the ground when at rest, so that the two upper members sloped gradually from front to rear.

To avoid weakening the frame by mortise and tenon

Mortise and tenon

The mortise and tenon joint has been used for thousands of years by woodworkers around the world to join pieces of wood, mainly when the adjoining pieces connect at an angle of 90°. In its basic form it is both simple and strong. Although there are many joint variations, the basic mortise and tenon...

 joints between the longitudinal members and the strut

Strut

A strut is a structural component designed to resist longitudinal compression. Struts provide outwards-facing support in their lengthwise direction, which can be used to keep two other components separate, performing the opposite function of a tie...

s, the latter abutted against the former and were held in place by right-angled steel brackets, which were bound to the wooden members by strips of Irish linen

Irish linen

Irish linen is the brand name given to linen produced in Ireland. Linen is cloth woven from, or yarn spun from the flax fibre, which was grown in Ireland for many years before advanced agricultural methods and more suitable climate led to the concentration of quality flax cultivation in northern...

 tape soaked in glue, the glue still being wet when the tape was bound, setting in situ. The corners of the angle brackets were both (a) indented at the apex to provide room for a steel pin and (b) provided with a horizontal slot across the corner, so that a bracing wire could pass through the slot and around the pin, thus enabling a simple, secure and easily replaceable mounting for the bracing wires which provided the frame with its stability. Each of the corners of each triangular set of struts was braced to the diagonally opposite corner of the adjacent set. This method of construction avoided the use of wood-screws, which could eventually become difficult to fix and were often found in other aircraft to damage the members they were intended to strengthen.

Wings and control surfaces

The main-planes comprised a wooden frame covered both top and bottom with Continental

Continental AG

Continental AG, internally often called Conti for short, is a worldwide leading German manufacturer of tires, brake systems, vehicle stability control systems, engine injection systems, tachographs and other parts for the automotive and transport industries. The company is based in Hanover, Germany...

 fabric (No. 100 B). The frame comprised two main spar

Spar

In sailing, a spar is a pole of wood, metal or lightweight materials such as carbon fiber used on a sailing vessel. Spars of all types In sailing, a spar is a pole of wood, metal or lightweight materials such as carbon fiber used on a sailing vessel. Spars of all types In sailing, a spar is a...

s and a set of shaped ribs

Rib (aircraft)

In an aircraft, ribs are forming elements of the structure of a wing, especially in traditional construction.By analogy with the anatomical definition of "rib", the ribs attach to the main spar, and by being repeated at frequent intervals, form a skeletal shape for the wing...

, spaced some 12 ins (0,30 m) apart, which provided an aerofoil camber. Each rib projected forwards beyond the front spar

Spar (aviation)

In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles to the fuselage. The spar carries flight loads and the weight of the wings whilst on the ground...

 and was fitted into the U-section of a rigid leading edge

Leading edge

The leading edge is the part of the wing that first contacts the air; alternatively it is the foremost edge of an airfoil section. The first is an aerodynamic definition, the second a structural one....

 member. The trailing edge

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 rejoins. Essential control surfaces are attached here to redirect the air flow and exert a controlling force by changing its momentum...

 was formed without such a rigid member. The wings were set at a dihedral angle, each main spar being rigidly fixed to the main frame at the required angle. The rear spar was attached to the frame by means of a single horizontal bolt fixed parallel to the longitudinal axis of the fuselage, which allowed the wings a degree of freedom to flex vertically when wing-warping was applied.

The tailplane was of similar construction, but the forward spar was more sturdy, because the whole tail-lane was pivoted about this spar, enabling it to act as an elevator

Elevator (aircraft)

Elevators are flight control surfaces, usually at the rear of an aircraft, which control the aircraft's orientation by changing the pitch of the aircraft, and so also the angle of attack of the wing. In simplified terms, they make the aircraft nose-up or nose-down...

.

The balanced rudder

Balanced rudder

The balanced rudder was an innovation in warship construction used as early as 1862 in the USS Monitor, one of the Union's first ironclads during the American Civil War...

 was made of 'Venesta' plywood. Macfie employed a sandwich

Sandwich structured composite

A sandwich-structured composite is a special class of composite materials that is fabricated by attaching two thin but stiff skins to a lightweight but thick core...

 construction, i.e. with a light framework glued between two 3-ply Venesta layers, thus combining lightness with strength.

Undercarriage

The Macfie Monoplane's undercarriage

Undercarriage

The undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land...

 comprised two main wheels (diameter approx. 26 in. (0.66m)) mounted below the engine, and a rear skid mounted on the sixth triangular brace from the front of the main body frame, i.e. about two-thirds of the distance back from front to tail. The two main wheels were attached, by two forked brackets, to the vertical members of a transverse rectangular chassis made of steel tubing, which transferred the weight of the engine at rest through the wheels to the ground. Each wheel was mounted behind its respective vertical member via two swivelling forked brackets, one horizontal and one sloping upwards at approximately 30 degrees, so that the two brackets and the vertical frame member formed a right-angled triangle. A helical compression spring on the vertical tube above the diagonal bracket provided a degree of sprung suspension while allowing the wheels, which were not steerable, to swivel independently.

The tail-skid was designed for use on sand; it comprised a lower horizontal 'shoe' which was fitted to a vertical wooden support by a single pivoted axle, the whole assembly being free to swivel about its vertical axis. The horizontal 'shoe' was rounded upwards at front and rear to allow it to ride over small undulations in the landing strip, its rotation about its axle being dampened at the rear by a length of steel spring and in front by elastic strip.

Engine

The engine, an air-cooled J.A.P. V8 providing 35 hp (26 kW), was mounted at the front on two timber extensions to the body frame, which were supported, when at rest, by the upper transverse member of the rectangular chassis to which the main wheels were attached (see above). The two-bladed solid teak

Teak

Teak is the common name for the tropical hardwood tree species Tectona grandis and its wood products. Tectona grandis is native to south and southeast Asia, mainly India, Indonesia, Malaysia, and Burma, but is naturalized and cultivated in many countries, including those in Africa and the...

 propeller, also made by Macfie, had a diameter of 6 ft. 6 in. (1.98 m.) and was mounted directly onto the crankshaft

Crankshaft

The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...

. During development it was found that removing part of the trailing edge of the blades "resulted in a considerable improvement in tractive effort".

Control

The pilot controlled the aircraft by means of a universally pivoted lever (i.e. what would later to be known as a joystick

Joystick

A joystick is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. Joysticks, also known as 'control columns', are the principal control in the cockpit of many civilian and military aircraft, either as a center stick or...

) to induce roll and/or pitch, and a pivoted footrest which operated the rudder (for yaw). The footrest controlled the rudder. The control lever, when moved forwards or backwards, operated the wires (via vertical cross-members attached to the tailplane spar) to rotate the whole tailplane, which acted as an elevator; when the lever was moved to the left or right, the attached wires warped the wings to induce roll.

Specifications