Helicopters are a fascinating piece of machinery that have revolutionized transportation and rescue missions. They are able to take off and land vertically and hover in place, making them incredibly versatile. Like any machine, helicopters are made up of a variety of parts that work together to make them functional.
Understanding the different types of helicopter parts is important for maintenance and repair. The main components of a helicopter include the airframe, fuselage, rotor system, engine, transmission system, fuel system, and electrical system. Each of these parts plays a crucial role in the helicopter’s ability to fly and operate smoothly.
Whether you are a helicopter enthusiast or a professional pilot, having a basic understanding of the different types of helicopter parts can help you appreciate the complexity and ingenuity of this incredible machine. In the following sections, we will explore the main components of a helicopter and their functions.
Main Rotor System
The main rotor system is the most important part of a helicopter as it provides the lift that allows the helicopter to fly, as well as the control that allows the helicopter to move laterally, make turns and change altitude.
Rotor Blades
Rotor blades are the most visible part of the rotor system and are responsible for generating lift. They are usually made of lightweight, high-strength materials such as aluminum or composite materials. The number of rotor blades varies depending on the helicopter design, with two or four blades being the most common. The shape and size of the blades can also vary depending on the intended use of the helicopter.
Rotor Hub
The rotor hub is the central part of the rotor system that connects the rotor blades to the main rotor mast. It is responsible for transmitting the power from the engine to the rotor blades and for controlling the pitch of the blades. The hub is usually made of high-strength materials such as steel or titanium, and is designed to withstand the stresses and forces generated by the rotor blades during flight.
Tail Rotor System
The tail rotor system is an essential component of a helicopter that helps to counteract the torque produced by the main rotor. It consists of tail rotor blades and a tail rotor gearbox.
Tail Rotor Blades
Tail rotor blades are small and narrow compared to the main rotor blades. They are mounted vertically or near-vertically at the tail of the helicopter and rotate to generate horizontal thrust in the opposite direction to the main rotor’s rotation. There are different types of tail rotor blades, including multi-bladed rotors, Fenestron from Airbus, NOTAR from MD helicopters, and helicopters with no tail rotor, like the Chinook.
Tail Rotor Gearbox
The tail rotor gearbox is responsible for transmitting power from the engine to the tail rotor blades. It is mounted at the end of the tail boom and is connected to the main rotor gearbox via a drive shaft. The tail rotor gearbox is designed to reduce the speed of the engine’s output and increase the torque transmitted to the tail rotor blades.
Transmission System
The transmission system is an essential component of a helicopter that transmits power from the engine to the rotor blades. It consists of the main gearbox, intermediate gearbox, tail rotor drive system, clutch, and freewheeling unit.
Main Gearbox
The main gearbox is the heart of the transmission system, which is responsible for transmitting power from the engine to the rotor blades. It is the most critical component of the transmission system and is usually located above the engine. The main gearbox also provides the necessary reduction in speed and torque to the rotor blades.
The main gearbox is designed to operate at high speeds and is subjected to high loads, making it a complex and robust component. It contains several gears, bearings, and shafts that must be lubricated and cooled to prevent overheating and damage.
Intermediate Gearbox
The intermediate gearbox is located between the main gearbox and the rotor blades. It provides a further reduction in speed and torque to the rotor blades. The intermediate gearbox is designed to operate at lower speeds and is subjected to lower loads than the main gearbox.
The intermediate gearbox is a simpler component than the main gearbox and contains fewer gears, bearings, and shafts. It is also designed to be easily accessible for maintenance and repair.
Engine Components
Helicopters are powered by engines that drive the rotor blades to lift the aircraft off the ground. The engine components of a helicopter include the turboshaft engine and the fuel system.
Turboshaft Engine
The turboshaft engine is the most common type of engine used in helicopters. It is a type of gas turbine engine that converts fuel into power to drive the main rotor blades. The engine consists of several components, including the compressor, combustion chamber, turbine, and gearbox. The compressor compresses the air entering the engine, which is mixed with fuel in the combustion chamber to create a high-temperature, high-pressure gas. This gas then passes through the turbine, which drives the gearbox that connects to the rotor blades.
Fuel System
The fuel system of a helicopter is responsible for storing, delivering, and managing the fuel that powers the engine. The fuel is stored in tanks located in the fuselage or wings of the helicopter. The fuel is then delivered to the engine through a series of pumps, filters, and valves. The fuel system also includes a fuel control unit that regulates the amount of fuel delivered to the engine based on the pilot’s input. The fuel system is critical to the operation of the helicopter and requires regular maintenance to ensure proper function.
Cockpit Controls
The cockpit of a helicopter is where the pilot sits and controls the aircraft. The controls in the cockpit are essential for the helicopter to fly and maneuver.
Collective Control
The collective control is located on the left side of the pilot’s seat, and it is used to adjust the pitch angle of the main rotor blades. When the collective control is raised, the pitch angle of the rotor blades increases, and the helicopter rises. When the collective control is lowered, the pitch angle of the rotor blades decreases, and the helicopter descends.
Cyclic Control
The cyclic control is located between the pilot’s legs and is used to control the direction of the helicopter. When the pilot moves the cyclic control forward, the helicopter moves forward. When the pilot moves the cyclic control backward, the helicopter moves backward. When the pilot moves the cyclic control to the left, the helicopter moves to the left, and when the pilot moves the cyclic control to the right, the helicopter moves to the right.
The cyclic control also controls the airspeed of the helicopter. When the cyclic control is moved forward, the helicopter gains speed, and when the cyclic control is moved backward, the helicopter slows down.
Landing Gear
Landing gear is an essential part of a helicopter that allows it to land safely. There are two types of landing gear used in helicopters: skid type and wheel type.
Skid Type
Skid type landing gear is commonly used in smaller helicopters. It consists of two skids that are attached to the bottom of the helicopter. The skids are made of metal or composite materials and are designed to absorb the shock of landing. Skid type landing gear is simple, lightweight, and easy to maintain. It is also less expensive than wheel type landing gear.
Wheel Type
Wheel type landing gear is commonly used in larger helicopters. It consists of two or more wheels that are attached to the bottom of the helicopter. The wheels are usually retractable and are designed to provide a smooth landing on hard surfaces. Wheel type landing gear is more complex and heavier than skid type landing gear. It is also more expensive and requires more maintenance.
Airframe
The airframe is the backbone of a helicopter, providing structural support and housing the cabin where the crew, passengers, and cargo are located. It is typically made of metal or composite materials, or a combination of both.
The airframe is divided into several sections, including the fuselage, which is the main body section that houses the cabin. The main rotor system is attached to the top of the fuselage, while the tail rotor is located at the rear of the fuselage.
The airframe also includes the landing gear, which is used to support the helicopter when it is on the ground. The landing gear can be fixed or retractable, depending on the type of helicopter and its intended use.
In addition to providing structural support, the airframe also plays a critical role in aerodynamics. It must be designed to minimize drag and provide stability during flight.
Overall, the airframe is a complex and essential component of a helicopter, providing the structural support and aerodynamic design necessary for safe and efficient flight.
