L.Opdyke French Aeroplanes Before the Great War (Schiffer)
Deleted by request of (c)Schiffer Publishing
This firm in Paris built at least 3 aircraft, 2 of which were helicopters; there is no record that any of them ever flew.
I: This one was shown without a motor at the Paris Exposition of 1909. 2 counter-rotating rotors each with 4 elliptical blades were driven directly from the engine mounted on its back low on a 4-wheel chassis; the rotors were built up like long thin wings, with spars and ribs. A smaller propeller was fitted at the rear for horizontal thrust, driven by a gear from the main shaft. Steering was done by the pilot's leaning, combined with a rudder hung at the tail. A fixed triangular vertical surface was set forward.
(Rotor diameter: 4 m; length: 4.25 m; 50 hp Farcot)
II: The second machine, an odd monoplane, was shown at the 1910 Paris Salon. A long uncovered triangular frame of square section had a small cruciform tail at the very end; the front end of the fuselage was a cubical box, all uncovered, with a motor driving a huge 3-bladed paddle tractor propeller; above was set a large angular low aspect-ratio wing with upturned tips.
III: This was displayed at the same Salon, marked Vuitton III. It was similar to No I, an uncovered 4-sided pyramidal frame on 4 wheels, with a central vertical drive-shaft and 2 counter-rotating rotors, the top one with 3 short blades, the lower with 2 long thin ones. The rear-mounted pusher propeller was still there, but the 2 vertical surfaces did not appear.
Flight, November 20, 1909
FLYER SILHOUETTES FROM THE PARIS SALON.
Helicopter with tandem lifting screws arranged to rotate in opposite directions. A third screw arranged as a propeller is intended to provide means for translation through space when the machine has once been raised from the ground. This latter propeller is of small diameter, but is driven at high speed, for the bevel-pinion on its shaft is one of those belonging to the reversing mechanism employed in the drive of the main screws. Provision is made for throwing the small propeller in and out of action at will by means of a jaw-clutch. The reversing gear, by means of which the lower lifting' screw rotates in an opposite direction to the upper, consists of two main bevel wheels in opposition and in mesh with a set of three planet pinions mounted in a stationary cage.
The pilot sits immediately in front of the vertical propeller-shaft, and the engine, not shown on the model exhibited, is placed beneath. At the pilot's left hand is a lever for working a progressive clutch which combines a reduction gear - of the epicyclic type - of such ratio that the speed of the vertical shaft is reduced to 500 r.p.m. In front of the pilot's seat is a fixed vertical triangular plane forming a prow to give steering-way, and behind the machine is a rudder.
The frame is built in pyramid form, mostly of bamboo, which is bound throughout with tape. Elsewhere hollow wood members are used.
The engine, when fitted, is to be of 120-h.p.; the machine weighs in its present state 169 kilogs. The lifting screws are 5 metres in diameter, and rotate at 500 r.p.m. The pitch is not given. The small propeller is 1.7 metres in diameter.