As far as its wing shape and construction are concerned, the Ago fighting biplane is in a class by itself since it is characterized by features not to be found on aeroplanes of any other make.
Top Speed: n.a.
Engine: six-cylinder Benz
Wingspan: 39 feet 3 inches
Weight: n.a.
Armament: n.a.
Specifications from “Practical Aviation,” by Charles Hayward, 1919
Planes
The wings, which have a span of 39 feet 3 inches, are marked by a pronounced taper from root to tip —a feature that has evidently been adopted, despite the manufacturing difficulties it involves, in order to cut the head resistance down by minimizing the number of interplane struts necessary. Only a single pair of outer struts is employed between the wings on each side; what appear to be inner struts are a single wire running from the upper forward spar to the lower forward spar and a single strut placed close to the body, no lift or landing wires being used between them. Doing away with the inner pair of struts also considerably increases the zone of fire of the machine mounted ‘en barbette’ in the after cockpit, as this enables the gun to fire ahead as well as astern.
Owing to the backward slope of the leading edge of the wings, the single pair of interplane struts is farther back than they would be in a normal airplane, while the taper also serves to bring them closer together, so that they obstruct the field to a lesser extent. The single inner strut on either side of the body naturally serves to brace the rear spars, these struts being placed in the wake of the single wires connecting the front spars. Since the decreased chord at the wing tips due to the taper localizes the travel of the center of pressure to a great extent, the absence of the inner front spar bracing is not as serious as it appears at first sight. The wing spars are of built-up construction and of the usual I-beam section, but gluing supplemented by tape and fabric are relied on entirely to fasten the flanges to the webs, no screws or nails being used. At the rib spacing points, a three-ply distance piece is glued into the hollow spar. Except for the extra hollowing out and the use of a heavier top than bottom flange, the rear spar is the same as the front, both being made of pine.
Steel tubing, streamlined with wood facing, is employed for the interplane struts, and they are further braced by a diagonal tube welded to them. In addition to this, a diagonal bracing wire, running in the opposite direction, is employed. Besides tapering transversely, the wings vary in thickness from root to tip, so that the ribs are not only of a different length but also of a different thickness at each point along the wing.
The ailerons, which have their tips set at a slightly smaller angle of incidence than that of the inner ends, are hinged to a fak- spar slightly to the rear of the main spar, this being characteristic of German design. The leading edge of the aileron is a steel tube, partly inclosed by and at some distance from a strip of laminated wood; this provides the requisite depth for the leading edge of the aileron. A short strip of very thin steel is bent around and soldered to the tube, the two ends of the strip projecting back into it slot in the rib.
Tail Unit
The tail planes are similar in construction to the main planes, the stabilizer being brought to the same level as the top of the body by dropping the lower longerons, somewhat after the fashion of the old Deperdussin monoplanes. A clip secures the front spar of the tail plane to the longerons, while the rear spar is attached by means of a sliding clip arrangement, which permits adjusting the angle of incidence of the tail.
The rudder is built up on a steel tubing frame and is mounted on the tail plane so that it moves with it. No great latitude of adjustment, therefore, is possible as a comparatively small movement of the rear spur of the tail plane brings the rudder against the edge of the cut-out portion of the fin. Owing to this construction, the rudder, which is also built on a steel tube frame, has no support above the body, as this is difficult to obtain in conjunction with an adjustable fin. As a result, the rudder is very much overhung and does not appear to have a very high factor of safety. The area of the tail plane is 24 square feet, that of the rudder is 8 square feet, and of the fin, 4 square feet.
Fuselage
The body is of the usual rectangular section with a light and comparatively flat structure forming a turtle back over the top of the main framework. This turtle back is a detachable unit. Square section pine longerons are used except for the engine hearers and here they are of ash. Forward, the body bracing takes the form of diagonally placed steel tubing, while, aft, steel tubing struts are used in connection with the usual wire bracing. The rear cockpit is occupied by the gunner, who is accommodated on a canvas scat stretched on a folding frame of steel tubing. When unoccupied, this seat is folded up out of the way and held by a spring, so that, the moment the gunner stands to fire, it folds up automatically. The gun is mounted on a swiveling bracket supported on a revolving wood gun-ring so that the gun may be traversed in any direction except for a small part of the circle, stops clipped to the rear legs of the cabane preventing the gun barrel from traveling too far inboard. The pilot’s seat in the forward cockpit is placed on top of the main gasoline tank, floor of the body, while a gravity service tank is mounted flush with the upper plane just to the left of the cabane. An opening in the wing is provided for this purpose. In a corresponding opening in the upper right-hand wing, the radiator is mounted, the gasoline and water being led through the steel tubes forming the right and left cabane legs, respectively, thus avoiding any exposed piping tur this purpose.
Power Plant
The power plant consists of a six-cylinder vertical water-cooled Benz engine mounted on the usual longitudinal bearers which are in turn supported by the body at three points. These are: at the rear, a sloping panel of laminated wood; in tilt1 center, tubes sloping up from the junction of the rear panel with the lower longerons; and at the front, a second laminated panel, this being placed vertically. In addition to these direct support?, the engine mounting is further braced by tubes to the upper longerons and by diagonal tubes from the top to the bottom longerons.
Controls
The controls are of the usual German type, with a vertical lever terminating at its upper end in a double-handled grip and mounted by means of a universal joint on a longitudinal rocking shaft. This shaft carries at its rear end the crank levers to which are attached the aileron control cables.