MD 902 Explorer is a multi-role helicopter.
McDonnell Douglas (McDonnell-Douglas) Helicopters Inc is an American aircraft manufacturer that existed until 1996, and after a merger with Boeing in 1997, they formed the Boeing Company, the largest aerospace corporation in the world.
Helicopter MD 902 (originally MD 900) is a multi-purpose helicopter that has been widely used in America, Europe and the world. Initially, the helicopter was developed under the designation 900, but in the process received a modified version of the 902 Explorer with improved insulation and avionics.
The history of the helicopter began in the 20th century, the design began in 1988. In 1992, the first flight was made on one of 10 prototypes, and in 1994 on a pre-production machine, as a result of which a certificate of airworthiness was obtained. In the same year, the first serial copy was presented and the production of the helicopter began. Moreover, it should be noted that a military version was being developed for the needs of the American army, one vehicle was presented.
Consider the technical characteristics of the MD helicopter. Composite materials are widely used in the design of the helicopter, most of the fuselage is made of carbon fiber reinforced plastic with lightning protection, in particular, the main rotor is made of composite. The design of the helicopter uses unique technical solutions and developments, but the most important is the NOTAR system, instead of the usual tail rotor, as a compensator for the reaction moment from the rotation of the main rotor.
Notar – no tail rotor, a system aimed at controlling the helicopter in yaw, relative to the vertical axis, by analogy with the usual tail rotors. The air flow, partly from the main propeller, is pumped into the space in the tail boom with the help of a compressor unit and accelerates along the beam with the help of a fan to the trailer, where the rotary nozzles are located. By changing the position of the nozzle, the pilot changes the direction of the airflow, which allows the helicopter to turn. Such a system does not require a shaft, a gearbox and other elements for transmitting rotation from the engine, as is the case with tail propellers, and there are also no propeller blades, which makes the operation of the helicopter quieter. The control system has automatic stabilization and autopilot. Such design features allow the helicopter to be very responsive, maneuverable and reliable.
The main rotor – 5 blades and 10.31 m in diameter, gives the helicopter stability and control efficiency during flight, maneuvering and hovering. The power plant is 2 x 630 h/p gas turbine Pratt Whitney Canada PW206E. The engine is powerful and reliable, has proven itself over the years on the positive side. The helicopter is gaining altitude at the rate of 14.2 m/s, depending on the load and weather conditions. Cruising speed is about 250 km / h, about the maximum possible 270 km/h. The maximum takeoff weight is 3130 kg, and the flight duration is 3.5 hours.
The helicopter is easily modified for various purposes and tasks, it is able to take on board 2 pilots and 7 passengers. Basically, the aircraft is used in police and rescue operations, like a medical helicopter.