Kaufmann No. 3 / No. 4
L.Opdyke French Aeroplanes Before the Great War (Schiffer)
Deleted by request of (c)Schiffer Publishing
No 3: Tested during June 1911, it flew in August; it was a rough copy of the pigeon-tailed Bleriot. The horizontal tail surfaces resembled those of No 2 and were set at a high angle of attack; the rudder, well aft of the tailplane, was similar to those used on the ACRs and the Thomanns, and like them was made of steel tube with bronze bearings. The whole machine may have been built of welded steel tube, either by Thomann or more likely, by Roux. The bent-wood tailskid and undercarriage may have been built by Bleriot, and the wheels were faired with fabric on the outsides. The wings curved downward slightly "'to improve the return to level flight after a bank"; Kaufmann seem to have believed that lift resulted from air pressure underneath the surfaces. A small flat fin was added aft of the rear cockpit. A later version of No 3 with 12-rib wings was described with a 50 hp Anzani; it was the first of the Kaufmann aeroplanes to fly.
(Span: 10.6 m; length: 7.6 m; 50 hp 6-cylinder Anzani)
No 4: This was the last of his designs, shown under the placard Type de Course at the 1911 Salon, with a triangular rudder and reduced angle of attack on the tailplane. The wings were long, and tapered to pointed tips, curved down like a bird's. A contemporary drawing shows still another wing arrangement, with gracefully upswept tips. The fuselage was narrow, with a wide-set undercarriage. A double-looped skid Bleriot-style held up the tail. This machine may never have been tested at all.
(Span: 11.6 m; length: 7.6 m; empty weight: 280 kg; payload: 180 kg; 90 hp 6-cylinder Anzani)
In 1913, Kaufmann graduated from the Ecole d'Aeronautique at about 24, and was appointed engineer by Louis Clement. He volunteered in WWI and flew Voisin bombers; in the course of the War he was wounded, and his aeronautical career was ended.
Flight, January 6, 1912.
PARIS AERO SHOW.
THE Kauffmann monoplane, while in its broad outline it has much in common with the general run of monoplanes, is chiefly remarkable for the size and shape of its wings. These are arched and turned up at the tips and are only a matter of 2 ft. in chord measurement.
The method of staying them is also interesting.
Four-stranded steel cables, two to each wing, take the weight of the machine in flight, and at a suitable distance from the wing these cables split up into a number of smaller wires, each of which is attached to its corresponding rib in the wing structure. By this system, although the head-resistance of the machine as a whole is increased, a great measure of security is obtained; in fact the constructors claim a safety factor of 25.
The main body is of the ordinary box-girder type, cross-braced with steel wire, and covered in in the front with aluminium sheeting and to the rear with fabric. A 50-60-h.p. radial Anzani motor, direct coupled to a Centrale propeller, is installed at the forward end of the fuselage. The tail is triangular in plan form, and does some of the share of the lifting. Hinged to it is the elevator, and the whole is protected from ground contact by a large flexible skid of malacca cane.
Warping is employed for lateral balance, this being operated, together with the elevating surface, from a central lever in the pilot's cockpit.
Principal dimensions, &c. : -
Length 24 ft. 8 ins. Weight 572 lbs.
Span 35 ft. Speed 85 m.p.h.
Area 154 sq. ft. Engine 50-60-h.p. Anzani.