CHAPTER
8 Helicopters and Autogyros
H
elicopters are very complicated aircraft. When compared with fixed-wing airplanes, they are slow, inefficient, unstable, and difficult to fly. Where they excel is in vertical takeoff and landing and the ability to fly low and slow and to stand still (to hover) in the air. This makes them an “angel of mercy” to those in distress, as well as a formidable weapons platform. In order to keep within the scope of this book, the discussion will be limited to single-rotor helicopters. A classic example is the Bell-47, shown in Figure 8.1, which was made famous in the Korean War. The large blades above the cockpit form the rotor, which provides the lift and propulsion of a helicopter. The smaller blades at the end of the The Bell-47 became the first fuselage form the tail rotor. The tail rotor’s prihelicopter to be licensed for civil mary function is to cancel the torque caused by operation in January 1947. the engine powering the rotor and to keep the fuselage pointed in the desired direction. To give you an idea of the range of sizes involved in single-rotor helicopters, the Bell-47G has a maximum takeoff weight of 2347 lb (1067 kg) and is powered by a single 200-hp engine, and the Mil Mi-10 (Figure 8.2), produced in the 1960s in the Soviet Union, is also a single-rotor helicopter with a gross weight of 95,100 lb (43,245 kg) and is powered by two 5500-hp engines. An
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