Flight, January 1924
THE COX-KLEMIN C.K.2 TRAINING BIPLANE
A MEDIUM-SIZED tractor biplane for training purposes and possessing several interesting features has recently been produced by the Cox-Klemin Aircraft Corporation, College Point, L.I., for the U.S. Army
Air Service. In this machine a tandem seating arrangement, located aft of the wings, is employed for both the pilot and the pupil. This not only facilitates instruction, but permits easy access to the cockpit, and also permits leaving the same with a parachute without interference with struts or wires.
The fuselage is of metal construction throughout, steel tube longerons and struts, with wire bracing, being employed. No welding is employed in its construction. A modified Fokker-type truss is employed for supporting the centre of the top plane from the fuselage. It differs from the original Fokker arrangement in that, whereas there are four struts in each truss in the Fokker, in the C.K.2 there are but three.
Both upper and lower wings are continuous from tip to tip, and are separated by a pair of N-struts. U.S.A.27 wing section is employed, which, being a thick section, permits the use of thick spars suitable for the Fokker type bracing. The spars are built up with spruce flanges, top and bottom, tapering from the centre to the tips, with plywood side members. Built-in spruce compression members and wire bracing are used in the construction of the wing frame work.
Ailerons are fitted to both upper and lower planes, the cables running through the lower wing and being connected to the control shaft lever by a bolt. When the wings are removed the controls are detached by simply removing this bolt, and the adjustment of the cables is not disturbed. The aileron cables are attached to a T-crank in the wing, which is connected to the aileron by a steel tube with an adjusting screw; the upper and lower ailerons are connected by an adjustable steel strut. The controls are of the stick type, and the stabiliser is adjustable when the machine is on the ground.
The instruments are located in the centre of the top plane, in which position they are clearly visible to the pilot and pupil at all times. The petrol tanks are mounted between the spars of the upper plane, 5 ft. out from the fuselage on each side, of the machine. This arrangement of the tanks minimises the risk of fire in the event of a crash, and also provides a good head for gravity feed.
A Wright model E, 190 h.p. eight-cylinder, water-cooled V-engine is employed, being mounted in the neatly rounded-off nose of the fuselage. The radiators are mounted on the sides of the fuselage, and are fitted with shutters operated from the cockpit.
The landing gear is of the "no-axle" type, the wheels being carried on two V's extending outwards from the bottom of the fuselage, and the shocks being taken by an absorber mounted on a vertical strut running from the wheel up to the side of the fuselage.
In conclusion it should be noted that this machine can be assembled very easily and quickly, as there are no bracing wires to fix or other adjustments to be made on the field.
The principal characteristics of the C.K.2 are :-
Span 29 ft.
Chord 5 ft. 6 ins.
Gap 5 ft. 2 ins.
Stagger 2 ft.
Wing area 293 sq. ft.
Wing section U.S.A.27.
Weight laden 2,400 lbs.
Loading per h.p. 12-62 lbs.
Loading per sq. ft. 8-18 lbs.
Speed range 47-125 m.p.h.