The Robinson R22 is a two-seat, two-bladed, single-engined, light utility helicopter manufactured by Robinson Helicopter Company. It was designed in 1973 by Frank D. Robinson, and has been in production since 1979.
The Kaman HH-43 Huskie is a helicopter developed and produced by the American rotorcraft manufacturer Kaman Aircraft. It is perhaps most distinctive for its use of twin intermeshing rotors, having been largely designed by the German aeronautical engineer Anton Flettner.
The Lockheed AH-56 Cheyenne is an attack helicopter developed by Lockheed for the United States Army. It rose from the Army's Advanced Aerial Fire Support System (AAFSS) program to field the service's first dedicated attack helicopter. Lockheed designed the Cheyenne using a four-blade rigid-rotor system and configured the aircraft as a compound helicopter with low-mounted wings and a tail-mounted thrusting propeller driven by a General Electric T64 turboshaft engine. The Cheyenne was to have a high-speed dash capability to provide armed escort for the Army's transport helicopters, such as the Bell UH-1 Iroquois.
The Hughes XH-17 "Flying Crane" was the first helicopter project for the helicopter division of Hughes Aircraft Company. The XH-17, which had a two-bladed main rotor system with a diameter of 134 feet, still holds the world record for flying with the largest rotor system. It was capable of flying at a gross weight of more than 50,000 pounds (23,000 kg), but proved too inefficient and cumbersome to be mass-produced beyond the prototype unit.
The Schweizer S300 series family of light utility helicopters was originally produced by Hughes Helicopters, as a development of the Hughes 269. Later manufactured by Schweizer Aircraft, and currently produced by Schweizer RSG, the basic design has been in production for over 50 years. The single, three-bladed main rotor and piston-powered S300 is mostly used as a cost-effective platform for training and agriculture.
On a helicopter, the main rotor or rotor system is the combination of several rotary wings with a control system, that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight. Each main rotor is mounted on a vertical mast over the top of the helicopter, as opposed to a helicopter tail rotor, which connects through a combination of drive shaft(s) and gearboxes along the tail boom. The blade pitch is typically controlled by the pilot using the helicopter flight controls. Helicopters are one example of rotary-wing aircraft (rotorcraft). The name is derived from the Greek words helix, helik-, meaning spiral; and pteron meaning wing.
The Hughes TH-55 Osage is a piston-powered light training helicopter produced for the United States Army. It was also produced as the Model 269 family of light utility helicopters, some of which were marketed as the Model 300. The Model 300C was produced and further developed by Schweizer after 1983.
The Lockheed XH-51 is an American single-engine experimental helicopter designed by Lockheed Aircraft, utilizing a rigid rotor and retractable skid landing gear. The XH-51 was selected as the test vehicle for a joint research program conducted by the United States Army and United States Navy to explore rigid rotor technology.
The Sikorsky S-69 is an American experimental compound helicopter developed by Sikorsky Aircraft as the demonstrator of the co-axial Advancing Blade Concept (ABC) with United States Army and NASA funding.
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of short take-off and landing (STOL) or short take-off and vertical landing (STOVL) aircraft cannot perform without a runway.
The Bell 207 Sioux Scout is a modified Bell 47 helicopter, developed by Bell Helicopter under contract from the United States Army, as a proof-of-concept demonstrator for the Bell D-255 helicopter gunship design, featuring a tandem cockpit, stub wings, and a chin-mounted gun turret.
The Seibel S-4 was a two-bladed, single-engine helicopter built by Seibel Helicopter. Designed by Charles Seibel, the S-4 was evaluated by the United States Army under the designation YH-24 Sky Hawk, but would be rejected for service. The S-4B would serve as the basis for the design of the Cessna CH-1 Skyhook, the only helicopter Cessna ever produced.
The Platt-LePage XR-1, also known by the company designation PL-3, is an early American transverse rotors helicopter, built by the Platt-LePage Aircraft Company of Eddystone, Pennsylvania. The winner of a United States Army Air Corps design competition held in early 1940, the XR-1 was the first helicopter tested by the USAAF, flying in 1941. The flight testing of the XR-1 proved troublesome, and although continued testing showed that the design had promise, other, improved helicopters were becoming available before the XR-1 was ready for service. As a result, the development of the aircraft was terminated in 1945.
The McDonnell XV-1 is an experimental Convertiplane developed by McDonnell Aircraft for a joint research program between the United States Air Force and the United States Army to explore technologies to develop an aircraft that could take off and land like a helicopter but fly at faster airspeeds, similar to a conventional airplane. The XV-1 would reach a speed of 200 mph, faster than any previous rotorcraft, but the program was terminated due to the tip-jet noise and complexity of the technology which gave only a modest gain in performance.
The Firestone XR-9, also known by the company designation Model 45, is a 1940s American experimental helicopter built by the Firestone Aircraft Company for the United States Army Air Forces. Only two were built.
The Kellett XR-8 was a helicopter built in the United States during World War II. It was a two-seat machine intended to demonstrate the feasibility of a twin-rotor system and, while it accomplished this, it also demonstrated a number of problems that prevented further development of this particular design.
The Bell Huey family of helicopters includes a wide range of civil and military aircraft produced since 1956 by Bell Helicopter. This H-1 family of aircraft includes the utility UH-1 Iroquois and the derivative AH-1 Cobra attack helicopter series and ranges from the XH-40 prototype, first flown in October 1956, to the 21st-century UH-1Y Venom and AH-1Z Viper. Although not flown in military service in the USA, the Bell 412 served in Canada and Japan and, like the UH-1Y, is a twin engine four rotor design based on the Bell 212.
The Filper ResearchModels Beta 200 and Beta 400 were small tandem, rigid rotor, helicopters intended for the personal helicopter market. Filper Research, located in San Ramon, California, was in existence from 1965 to 1968. The Beta 200 was a two place helicopter and the Beta 400 was a four place helicopter. One Beta 200 prototype and one Beta 400 prototype were manufactured and flown. Several pre-production airframes, which never flew, were also manufactured. Development testing was done in the experimental category. Development was not completed and Filper did not apply for an FAA Type Certificate for either type. There were several other variations on the basic Beta design which were contemplated but these were never developed beyond the conceptual stage. There was a fatal crash of the Beta 400 prototype in November 1967 and the company ceased operations in April 1968.
The Hiller XH-44 Hiller-Copter is an American experimental helicopter designed by Stanley Hiller.
The Nagler-Rolz NR 54 is a German experimental foldable backpack helicopter developed during World War II. An enlarged variant, the NR 55, was also built.
