L.Opdyke French Aeroplanes Before the Great War (Schiffer)
Deleted by request of (c)Schiffer Publishing
Borel-Ruby: Before the development of machine-gun synchronizers, designers had experimented with several generally unsatisfactory solutions; one was the pusher biplane with forward-mounted gun; another, less common and less satisfactory, was the so-called "torpedo" aeroplane with the propeller mounted behind the tail, like the Tatin monoplane. In 1913 Borel built such a monoplane, sometimes known as Ruby-Borel, sometimes simply as Ruby.
It had Borel warping wings, but the rectangular-sectioned fuselage was partly of metal, with a pointed nose and the aft fuselage sharply tapering to the propeller hub. The pilot sat ahead of the wing, with the 70 hp Gnome inside the fuselage at his back, driving the pusher propeller mounted at the very tip of the rear fuselage through a shaft more than 5 m long, which may have caused problems. The gunner/observer sat in front with the machine-gun mounted on the cowl in front of him - sometimes replaced with a high windshield. Ports for cooling were let into the side of the fuselage aft of the motor. Vertical fins were set above and below the rear fuselage; the elevators trailed back in an arc behind the propeller, and together with the trailing wingtips, gave the machine a faintly bat-like appearance.
The Torpedo met with no success with the Army, nor did other efforts by Borel and Bleriot to build monoplanes with forward-firing guns.
(Span: 9 m; length: 7 m; 70 hp Gnome)
Flight, December 27, 1913.
THE PARIS AERO SALON - 1913.
The remaining machine - the "Ruby" - is undoubtedly the most interesting on the stand, as it represents a very radical departure not only from usual Borel design, but from aeroplane design in general. The raison d'etre of this machine is the consistent demand of the military authorities, for a machine in which the propeller is mounted behind the main planes, while the pilot's and observer's seats are situated well out in front, partly to facilitate observation and partly to allow of a gun being mounted in such a manner that it may be fired in all directions without the propeller interfering with it.
The fuselage, which is of rectangular section, and which tapers gradually towards the bow and the stern, is built up of four longerons of ash, connected by struts and cross-members of spruce. In the central part of the fuselage, and between the two planes, is mounted the engine - a 50 h.p. Gnome - which drives, through a long shaft, a small propeller situated behind the tail-planes. Where the four longerons converge in the rear of the fuselage, is a ball thrust bearing which relieves the long shaft of all end thrust. In the front part of the fuselage are arranged the seats for the pilot and passenger, the pilot occupying the front seat. In front of him is a Hotchkiss machine gun mounted on the apex of a structure of three steel tubes secured to the nose and upper longerons of the fuselage, respectively. Control is by means of a single central steel tube, which operates the warp and elevator, whilst a pivoted foot-bar actuates the rudder.
The chassis is of a very simple form, and consists of two pairs of ash struts, each pair forming a V. Two stub axles, which are pivoted on another pair of V struts, and work in slots between the chassis struts, are sprung from these by means of rubber shock absorbers.
The tail planes, which are of rather unusual shape, as well as the tail skid, are illustrated by one of the accompanying sketches.