Aviation Technical English for aircraft maintenance engineers (Авиационный технический английский язык для студентов-авитехников)

73 backwards, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft would usually not be able to take off or land. The capability to efficiently hover for extended periods of time allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft cannot perform. A helicopter main rotor or rotor system is the combination of a rotary wing and a control system that is used to generate both the aerodynamic lift force that supports the weight of the helicopter, and thrust which 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 is connected through a combination of drive shaft(s) and gearboxes along the tail boom. A helicopter’s rotor is generally made up of two or more rotor blades. The blade pitch is typically controlled by a swashplate connected to the helicopter flight controls. Helicopters are one example of rotary-wing aircraft. *https://simple.wikipedia.org/wiki/Helicopter_rotor (05.10.2018). BASICS OFVIBRATION Occasional airplane vibration during flight is not unusual. There are many causes of airplane vibration, including landing gear extension and retraction, extension of speed brakes, free play in movable surfaces, and systems malfunctions. Flight crews need to understand the causes and effects of airplane vibration so that they can take appropriate action to maintain flight safety and prevent excessive wear or airframe damage. In addition, flight crews can contribute to accurate reports of in-service events that will facilitate trouble-shooting and maintenance activities. Understanding the possible sources of vibration and the information needed to isolate and correct vibration problems requires knowledge of the following: – Types of vibration and noise; – Causes of airplane vibration; – Detection of airplane vibration; – Flight crew response; – Maintenance troubleshooting.