Flight, December 1939

AN AMERICAN EXPERIMENT

   PIONEERING in the field of aeroplane construction by the “plastics” method, officials of the Timm Aircraft Corporation at Los Angeles expect to see their first type in the air and undergoing flight tests this month. Research and experiments have been under way foi approximately a year, and actual construction is practically completed.
   Briefly stated, the process used by the Timm organisation (known as “Nuyon”) calls for a triple criss-cross laminated spruce plywood which is heavily impregnated with phenol formaldehyde, a substance similar to the well-known bakelite. The resultant sheet may be formed to shape by the application of heat and pressure.
   The wing is of full cantilever construction. The skin is formed of two moulded halves of the impregnated plywood fitted over the conventional type of spars and ribs and bonded and sealed at all points of contact by the same phenol process. Laminated solid rectangular “Nuyon-processed” spruce spars are used, and the ribs are of the three-ply resinous-bonded plywood.
   The fuselage is of semi-monocoque construction consisting of spruce longerons, laminated spruce frames and bulkheads covered with and bonded to a moulded “Nuyon” shell, made in two half sections. The fixed surfaces of the tail-unit, and the flaps, are of similar construction to the wing, but the control surfaces are of metal-frame construction, fabric-covered.
   The initial product of this type is a two-seater, open tandem, military-type training monoplane designated the PT 160-K. It has a span of 35 feet, an overall length of 26 feet 4 inches and stands 7 feet in height. The wing is an NACA 23015 aerofoil at the root and tapered to NACA 23012 at the tip. Empty the aeroplane weighs 1,426lb. and its gross weight is 2,050lb. The company plans to produce these trainers with engines from 125 to 220 h.p.
   Performance, based on 160 h.p., is estimated as follows: High speed, at sea level, 137 m.p.h.; landing speed, 48 m.p.h.; climb, at sea level, 971 feet per minute and to 10,000 feet in 14.4 minutes; service ceiling 17,800ft., cruising range 4 hrs. or 500 miles.
   Upon completion of the trainer the company expects to start construction on a military type of the same materials, which will be based on a revision of the Howard Hughes racer which now holds the west-east trans-Continental record of seven hours and twenty-nine minutes. Design rights to this were recently purchased and the revised design has been completed. In this a 1,250 horse-power engine will be installed which is expected to propel it at a speed in excess of 400 m.p.h.