The most famous and widely used American airplane of the World War One era. In the 1920’s countless ‘barnstormers’ flew Jennies in flight exhibitions all over the United States. The Curtiss tractor was identified by its manufacturers as Model JNB-4 and was been largely used for training purposes during the war.
Specifications from “Practical Aviation,” by Charles Hayward, 1919
Planes
The span of the upper plané is 43 feet 7 ½ in while that of the lower is 33 feet ll ¼ inches, the chord being practically 6 feet, the gap 5 feet 2 1/2 inches, the stagger 1 foot, and the total area approximately 325 square feet. The wing curve is Eiffel No. 36, the upper wing being built in three sections, consisting of a center, or engine, panel and two outer sections. There is a dihedral angle of 1 degree and the wings have an angle of 2 degrees. I-beam section spruce beams are used for the wing construction with trailing edges of flattened steel tubing and pine o i reinforced with birch strips. The ailerons each have an area 17.6 square feet and in cross-section they conform to the contour of the main panels from rear beam to trailing edge. Due to the difference between the span of the upper-and the lower wing, there, is a considerable overhang, which is braced by four masts. The wings are covered with linen protected by several coats of waterproofing “dope”, which is used on all aeroplane wings.
Tail Unit
The horizontal stabilizing plane has an over-all length of 9 feet 3 inches and a maximum depth of 3 feet 0 inches, giving it a total area of 28.7 square feet. It is of the nonlifting type and is supported from beneath by a pair of steel tube braces. The elevators measure slightly over 10 feet along their trailing edges and a little less than 3 feet in depth and have an area of 11 square feet each. The rear member of the fuselage is extended upward to form a support for the triangular vertical fin, which has an area of 3.8 square feet. Bracing guys are carried from the upper edge of this fin around the outer edges of the horizontal stabilizer and attached to the fuselage below. The rudder inea- tires approximately 5 by 3 feet and has an area of 12 square feet. It is built on a steel frame, consisting of the rudder post of steel tubing to which flattened tubing is brazed to form the trailing edge. Metal straps brazed to this tubing at intervals form supports to which art- attached spruce ribs comprising the framework for the fabric covering. It is mounted on three hinges and is designed to have a swing of 30 degrees on either side of the longitudinal axis of the fuselage. The elevators have a similar radius of action in a vertical plane.
Power Plant
The motor is a Curtiss eight-cylinder water- cooled V type measuring 4 by 5 inches and designed to have a normal speed of 1400 r.p.m., at which its rating is 90 h.p. on a fuel consumption of 0.6 pound per brake horsepower per hour. Including the muffler, the complete motor weighs 410 pounds, while its fuel supply, including the weight of the tank and piping, adds another 154 pounds. The radiator and its connections when filled with water weigh 96 pounds, while the propeller accounts for 20 pounds of the total, which is 1890 pounds. As the total supporting area is 360 square feet this gives a loading per square foot of supporting surface of 5.26 pounds. The loading per rated horsepower of the motor is 21 pounds.
Landing Gear
The landing gear is of the two-wheeled V type with streamlined struts, having a tread of 5 feet 3 inches and equipped with 26- by 4- inch wheels. The tail skid is of conventional pattern, while at the outer inter-plane struts rattan wing skids are fitted. The total weight of the landing gear, including tlit-r wing-tip skids, is about 105 pounds.
Controls
Aeroplanes designed for training purposes are naturally always built so that they may be controlled either from the pilot’s or the observer’s cockpit — in training, the student’s or the instructor’s seat. This particular model is equipped, as specified, all with Deperdussin control at both seats or Deperdussin at one seat and Curtiss control at the other in the order desired.