CLASSIC AIRCRAFT - THE BOEING STEARMAN

By Luzanne Keyter

The Stearman Kaydet today still retains an aura of nostalgia similar to that of the De Havilland Tiger Moth. It all started with the Stearman Aircraft Company, also known as the Wichita Division of the Boeing Airplane Company, formed by Lloyd Stearman in 1927.



As a private venture, Stearman designed the Stearman Model C and soon after, the redesign and construction of a new training biplane, the Stearman X-70, began. This aircraft was first flown in December 1933 and was a contender to meet a US Air Corps requirement for a new primary trainer in 1934.



The US Navy was the first to show positive interest in the aircraft and placed an order for 61 of the Stearman Model 70 aircraft under the designation NS-1 (Trainer, Stearman, 1). When received, the US Navy changed the original power plant to 225-hp (168-kW) Wright J-5 (R-790-8) radial engines and the company changed the model number of the aircraft to Model 73.



In early 1936, the X-70s received by the US Army was subjected to protracted testing and eventually the USAAC contracted for the supply of 26 aircraft under the designation PT-13 (Primary Trainer, 13). These, powered by 215-hp (160-kW) Lycoming R-680-5 engines, were the first of the Stearman Model 75 series.



The careful approach was not a reflection upon the capability of the new trainer, for at the time the USAAC had little money to spend on new aircraft. But as the war began, Boeing was contracted for thousands of Stearman-designed trainers, produced under the designation Boeing Model 75 but persistently regarded as Stearman 75s. The pet name Kaydet was also used to refer to the aircraft but remained unofficial except in Canada where it originated.



The two-seat biplane was of mixed construction. The single-bay wings being of wood with fabric covering and the remainder of welded steel tube with mostly fabric covering. The landing gear was of non-retractable tail wheel type and the power plant varied considerably throughout the production run which lasted until early 1945. During this time, over 10 000 Stearman 75 aircraft were manufactured.



The USAAC continued to modify the Stearman 75 aircraft and soon an entire range of aircraft was being used in the war. The PT-13A had improved instrumentation, the PT-13B only minor equipment changes. The PT-13C was fitted with additional equipment necessary to make them suitable for night or instrument flying. The PT-17 was produced to meet the enormous demand for training aircraft. The PT-17A was equipped with blind-flying instrumentation and the PT-17B with agricultural spraying equipment for pest control.



The US Army procurement during this same period included the N2S-1, N2S-2, N2S-3, N2S-4 and N2S-5, the PT-13D, PT-18 and PT-18A - all with only adjustments to the aircraft's power plant.



At the end of the war, the surplus of Stearman aircraft was seen used by air forces of other nations and large numbers were converted for the use as agricultural aircraft and some still remain to serve this purpose today.

Specifications: Boeing Model E-75

Powerplant:

One 220-hp (164-kW) Avco Lycoming R-680-17 radial piston engine

Performance:
Maximum speed - 124 mph (200 km/h)
Cruising speed - 106 mph (171 km/h)
Service ceiling - 11,200 ft (3,415 m)
Range - 505 miles (813 km)

Weights:
Empty - 1,936 lb (878 kg)
Maximum take-off - 2,717 lb (1,232 kg)

Dimensions:
Wingspan - 32 ft 2 in (9,80 m)
Length - 25 ft 0.25 in (7,63 m)
Height - 9 ft 2 in (2,79 m)
Wing area - 297,0 sq ft (27,59 sq m)


In 1928 an English female aviator, Lady Mary Heath became the first person to fly what later became know as the Imperial Airways route between Cape Town and England in her Avro Avian biplane. In 2013, 85 years later, Tracy Curtis-Taylor, one of the Shuttleworth Collection display pilots, reinacted the historic flight in a specially restored Stearman biplane, the Spirit of Artemis.

On 2 November 2013 Curtis-Taylor took of in Cape Town and started the two month long journey. Covering over 10 000 miles in 110 flying hours, Curtis-Taylor and the Stearman made a safe landing at their final destination, Goodwood airfield in England after pit stops in Africa and the Mediterranean.






Aircraft Technical
Classic Aircraft








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