Hughes TH-55 Osage

In 1955, Hughes Tool Company's Aircraft Division carried out a market survey which showed that there was a demand for a low-cost, lightweight two-seat helicopter. The division began building the Model 269 in September 1955. It was initially designed with a fully glazed cockpit with seating for two pilots, or a pilot and passenger. It also had an open-framework fuselage and a three-blade articulated rotor. The prototype flew on 2 October 1956, but it wasn't until 1960 that the decision was made to develop the helicopter for production. The original truss-work tailboom was replaced with a tubular tailboom and the cockpit was restructured and refined prior to being put into production, resulting in the Model 269A. With this model, Hughes successfully captured a large portion of the civilian helicopter market with an aircraft that would prove itself popular in agriculture, police work and other duties. == Design ==

The Hughes 269 was designed with a fully articulated, three-blade main rotor designed by Drago Jovanovich, and a two-blade tail rotor that would remain as distinctive characteristics of all its variants. It also has shock absorber-damped, skid-type landing gear. The flight controls are directly linked to the swashplate of the helicopter so there are no hydraulic systems in the 269. There are generally two sets of controls, although this was optional on the civil 269A. For three-seat aircraft, the middle collective control stick is removable and a seat cushion can be put in its place for the third passenger. == Operational history ==

, California in 1966. In 1958, prior to full-time production, Hughes provided five preproduction Model 269A examples to the U.S. Army for evaluation as a light observation helicopter to replace the aging OH-13 Sioux and OH-23 Raven. Designated as the YHO-2HU the helicopter was eventually turned down. On 9 April 1959, the 269A received certification from the FAA. Hughes continued to concentrate on civil production, and deliveries of the Model 269A began in 1961. By mid-1963 about 20 aircraft were being produced a month and by the spring of 1964, 314 had been built. While the U.S. Army had not found the Model 269A adequate for combat missions, in 1964 it adopted a modified version of the 269A as its training helicopter to replace the TH-23 and designated it the TH-55A Osage. In 1986, Schweizer acquired all rights to the helicopter from McDonnell Douglas, who had purchased Hughes Helicopters in 1984, and renamed it McDonnell Douglas Helicopter Systems. For a few years after, Schweizer acquired the FAA Type Certificate known as the Schweizer-Hughes 300. While Schweizer made over 250 minor improvements, the basic design remained unchanged. Between Hughes and Schweizer, and including foreign-licensed production civil and military training aircraft, nearly 3,000 copies of the Model 269/300 have been built and flown over the last 50 years. That would have been the end of the story, but Schweizer continued to develop the model 300 by adding a turbine and redesigning the body to create the model 330m, and then further developed the dynamic components to take greater advantage of the power of the turbine engine; this led to the development of the Model 333. == Variants ==

Model numbers ;269 :Two prototype aircraft powered by a 180 hp Lycoming O-360-A engine and had a truss tailboom. First flown on 2 October 1956. ;269A :Replacing the prototype's truss tailboom with a simple aluminum tube as the tailboom, the 269A came with the option for several models of Lycoming O-360 engines: the carbureted O-360-C2D, restricted to in the 269A, or the carbureted HO-360-B1A/B1B or fuel-injected HIO-360-B1A/B1B, all rated for in the 269A. Customers also had the option for dual controls, and a 19 gal (72 liter) auxiliary tank. The maximum weight was ; later this could be increased to if certain modifications were performed. ;269B "Model 300" :Featuring a three-seat cockpit, the 269B was powered by a 190 hp (141 kW) Lycoming HIO-360-A1A engine and was marketed as the Hughes Model 300. Optional floats were also available on the 300, the first time available on any 269-variant. ;280U :single-seat, utility version of the 269B with an electric clutch and trim system. The 280U could be fitted with spraying equipment for agricultural applications. ;300AG :269B designed specifically for agricultural spraying with a 30 gal (114 liter) chemical tank on each side of the fuselage, and a 35 feet (10.67 m) spray boom. ;300B :269B with a Quiet Tail Rotor installed to reduce exterior noise levels to that of a light airplane. The QTR was installed on all production models starting in June 1967 and offered as a kit for previously built aircraft. ;269C "Model 300C" :The 300C was powered by a 190 hp (141 kW) Lycoming HIO-360-D1A and had a larger diameter main rotor - compared to . The larger rotor and engine giving it a 45% performance increase over previous 269-models. Hughes and Schweizer both marketed the 269C as the Model 300C. ;NH-300C :License-built 269C by Italian aircraft manufacturing firm BredaNardi. ;300C Sky Knight : Police patrol version of the Model 300C. ;TH-300C: Military training version. Military designations ;YHO-2 :Five 269A aircraft were evaluated by the U.S. Army for an observation helicopter in 1957-58, originally designated XH-42. The Army did not order the YHO-2 due to lack of funds. ;TH-55A :Military version of the 269A-1 (Model 200) built for the U.S. Army as its standard primary training helicopter Although basically the same as the Model 200, the TH-55A was fitted with military radio and instrumentation. 792 TH-55As were purchased by the Army between 1964 and 1967. An experimental TH-55A was fitted with an Allison 250-C18 turboshaft engine, and another would be fitted with a Wankel RC 2-60 rotary engine. ;TH-55J :38 license-produced versions of the TH-55A, built by Kawasaki for the Japanese Ground Self-Defense Force. ;IH-2 :Brazilian Navy designation for the Model 269A. Originally designated HTH-1. ;IH-2A :Brazilian Navy designation for the Model 269A-1. ;IH-2B :Brazilian Navy designation for the Model 269B. == Operators ==

; • Algerian Air Force ; • Brazilian Navy ; • Colombian Air Force ; • Ministry of Public Security ; • Haiti Air Force ; • Honduran Air Force , Germany ; • Indian Navy ; • Japanese Ground Self-Defense Force ; • Peruvian Air Force ; • Philippine Air Force- 2 units ; • Sierra Leone Air Arm ; • Spanish Air Force ; • Swedish Army ; • Republic of China Army ; • Royal Thai Army ; • Turkish Army ; • United States Army == Specifications (Hughes 300) ==