Aircraft structure terminology explained, what is the structure of an airplane

Wingspan - the straight-line distance between the left and right wingtips of the wing (or tail) (the part that passes through the fuselage should also be counted).

The full length of the fuselage - the straight-line distance at the very front of the aircraft.

Center of gravity - The point of force of gravity of each part of the model is called the center of gravity.

Tail arm - the distance from the center of gravity to the length of the leading edge of the tail 1 4 chord.

Airfoil - the planed shape of the wing (or tail).

Leading edge - the very front end of the airfoil.

Trailing edge – the rearmost end of the airfoil.

Wing chord - the line between the front and rear edges.

Aspect ratio - the ratio of wingspan to wingstring length. A large aspect ratio indicates that the wing is narrow and long.

Sharpening ratio - refers to the ratio of the chord length of the tip of a trapezoidal wing to the chord length of the wing root.

Upper reverse angle - the angle between the leading edge of the wing and the transverse axis of the model aircraft.

Sweep angle - the angle between the leading edge of the wing and a straight line perpendicular to the centerline of the fuselage.

Wing mounting angle - the angle between the wing chord and the reference line used for fuselage measurement.

Wing angle of attack - the angle between the wing chord and the oncoming air flow from the wing.

Wing load – the amount of flight weight carried per unit lift area.

Total lift area - is the sum of the total area of the wings and the horizontal and tilted tail area of the model aircraft when it is in horizontal flight.

Wingchord: A line segment that connects the front and trailing edges of a wing cross-section. When there is a relative motion between the wing and the airflow, the angle between the direction of the airflow and the wing chord is called the angle of attack.

The lift is greatest when the wing is at a critical angle of attack, and within the critical angle of attack, increasing the angle of attack increases the lift and drag. The curves for increasing lift and drag are different, so there is an angle of attack with the largest lift-to-drag ratio, which is called a favorable angle of attack. The angle of attack when the lift is zero is called the zero rising angle of attack.

The zero-liter angle of attack is a negative value. The angle of attack is below zero and the angle of attack lift is negative. After exceeding the critical angle of attack, the lift decreases and the drag increases sharply.

Angles of attack exceeding critical angles of attack are the root cause of aircraft stalls. The angle of attack of the wing is a fixed value when the aircraft is in level flight. Pilots can change the angle of attack, change lift and drag, and flexibly operate the aircraft with the change of throttle. 2

Most aircraft consist of five main parts: wings, fuselage, tail, landing gear, and power plant.

Aircraft structure. The main function of the wing is to provide lift for the aircraft to support the aircraft in the air, and also play a certain role in stabilization and maneuvering. Ailerons and flaps are generally installed on the wings.

Manipulating the ailerons allows the aircraft to roll; Lowering the flaps increases the lift coefficient of the wing. In addition, engines and landing gear can be installed on the wings.

and fuel tanks, etc. Wings come in a variety of shapes and in different numbers. In the early days when aviation technology was not developed, in order to provide greater lift, aircraft were mainly biplanes or even multiplanes, but modern aircraft are generally monoplanes.

In the process of wing design, a contradiction often mentioned is the stability and operability of the aircraft. The lower monoplane is like a vase held up, and the maneuverability is very flexible, but the stability is slightly inferior.

However, considering the shielding effect of the wing on engine noise and the ease of maintenance, large civil airliners generally adopt a lower single-wing design, and at the same time adopt an upper reverse angle installation to improve maneuverability.

The main function of the fuselage is to load crew, passengers, goods, and various equipment; Other parts of the aircraft such as the tail, wings and engines can also be connected into a single unit. But the flying wing is the fuselage that is hidden inside the wing.

It is mainly composed of fuselage, wings, wing tail, landing gear, and power plant.

Fuselage: The main function of the fuselage is to load crews, passengers, goods, and various equipment; Other parts of the aircraft such as the tail, wings and engines can also be connected to form a complete tail.

Wings: The main function of a wing is to generate lift to support the aircraft in the air; It also plays a certain role in stabilizing and manipulating. Ailerons and flaps are generally installed on the wings. Manipulating the ailerons allows the aircraft to roll; Lowering the flaps increases the lift of the wings.

Tail: includes horizontal tail and vertical tail. The horizontal tail consists of a fixed horizontal fixed surface and a movable elevator.

The vertical tail consists of a fixed vertical stabilizer and movable rudders. The main function of the tail is to control the pitch and deflection of the aircraft, and to ensure that the aircraft can fly smoothly.

Landing gear: Landing gear is used to support an aircraft and enable it to take off, land and park on the ground and at the level. The landing gear of land aircraft is mostly composed of shock-absorbing struts and wheels. It is used to support aircraft during take-off, landing, taxiing, ground taxiing and parking.

Powerplant: The powerplant is mainly used to generate pull or thrust to move the aircraft forward. Secondly, it can also provide power supply for electrical equipment on the aircraft, and provide air source for gas equipment such as air conditioning equipment.

Precautions for flying:

First, there are a few things you have to pay attention to:

1. It is best to arrive at the airport 1 hour in advance.

2. Remember to bring your ID card and air ticket.

3. Be sure to complete the formalities half an hour before the plane takes off. Because some airports are very strict, if you don't let it do it when the time comes, you won't let it be done, then you will be in trouble.

Second, if you have MP4 or a notebook, you can bring it with you, and you can take it on the plane after passing through the security check and handing it over to the security inspector for inspection. The aircraft is not usable during take-off and landing, and it also needs to be turned off.

3. Other precautions:

When you enter the cabin, you can give your seat card to the cabin crew and ask him to guide or guide you to your seat. Once you have reached your seat, you can place your carry-on baggage in the overhead compartment. Coats or rain gear can be handed over to the flight attendant for safekeeping, and if you need anything along the plane, you can also ask the flight attendant for help, you are welcome.

Before and after take-off and landing, the aircraft shakes badly, so you should wear a seat belt and do not smoke.

The structural components of the aircraft are shown below:

The main components of conventional aircraft are the fuselage, wings, tail, landing gear, power system, flight control system, avionics system and airborne equipment.

1.The wing is the main component that generates lift. Ailerons for lateral maneuvering and flaps for increased lift are also mounted on the wings.

2.The powertrain includes the engine and some ancillary systems such as fuel, lubrication, heat dissipation, intake and exhaust, etc., which provide the thrust (or pull) force that enables the aircraft to overcome the drag experienced while flying. <>

3.The tail of an aircraft usually includes a horizontal tail and a vertical tail, and its main function is to ensure the balance of the aircraft and control the aircraft.

4.The landing gear is used for take-off, landing, and ground parking of aircraft.

5.The main function of the fuselage is to load equipment, crew and cargo.

6.The control system is used to transmit control instructions and control the flight attitude of the aircraft.

7.Airborne equipment includes flight instruments, communications, navigation, environmental control, life support, energy supply and other equipment, as well as some airborne equipment related to aircraft use, such as fighter aircraft and fire control system, passenger aircraft cabin life service facilities, etc.

The fuselage can be divided into three forms according to the force characteristics of its structural elements.

Beam fuselage: 4 truss girders bear all or most of the bending normal stress of the fuselage. The skin of the abrasive socks is thin and only subjected to torque and lateral shear forces. There are fewer stringers and are used to support the skin or to withstand a small amount of axial force.

This structural form is mostly used in parts with more mouth caps on the fuselage. For example, the front fuselage of the fighter aircraft has a much brighter opening (cockpit cover, nose landing gear hatch cover, electronic equipment cabin and ** hatch cover, etc.), the skin cannot be stressed, and a beam structure should be used.

Semi-monocoque fuselage: no strong trusses. The dense stringers are subjected to bending normal stresses together with the skin. This structure is lightweight, and most of the parts of the fuselage with fewer openings are used in this structural form.

Monocoque body: no trusses and trusses. In order to improve the support of the skin, a dense ordinary frame is arranged along the length of the fuselage, sometimes called a dense frame structure.

It is generally used in parts where the bending moment is small and there is no large opening. Some light aircraft use a monocoque fuselage for ease of manufacture.

Rigid wing structure.

Rigid wings are still the wing construction of most aircraft. The wings of modern aircraft are generally made of aluminum and magnesium alloy materials. There are spars and stringers inside the wing along the span direction, and ribs or bulkheads along the chord direction, of which the spar is the main load-bearing member.

The skin wheel is fixed to the internal structure by riveting and bears part of the load on the wing.

In flight, the aerodynamic loads acting on the wings are first applied to the skin and stringers, transmitted to the ribs through rivets and connecting corners, and then to the spars, and finally to the fuselage through the spars. On the lower surface of the wing, an appropriate position is provided with an inspection port, an oil drain port and an aircraft jacking seat. In order to better drain stagnant water, there are also excretion openings on the lower surface of the wings.

The fuselage structure of the aircraft includes: fuselage, wings, engines, landing gear, tail, control system, and aerodynamic structure.

1. Fuselage: The main part of the aircraft is divided into three parts: head, middle and tail, which can be divided into steel aluminum alloy, carbon fiber and other materials.

2. Wing: used to support the weight of the aircraft and provide lift for the aircraft.

3. Engine: provides the thrust and power of the aircraft, usually composed of multiple engines.

4. Landing gear: It is used to maintain the balance of the aircraft and support the weight of the aircraft when it is on the ground, and plays a role in shock absorption during take-off and landing.

5. Tail: used to control the stability and maneuverability of the aircraft.

6. Control system: It is composed of a control stick, pedal and instrument panel in the cockpit, which is used to control the flight attitude and speed of the aircraft.

7. Aerodynamic structure: used to control the aerodynamic performance of the aircraft during flight, such as flaps, slats and ailerons.

The history of the development of aircraft

Humans have always dreamed of flying, trying various ways to achieve it. In prehistoric times, people depicted flying animals and mythological figures such as flying gods, flying birds, and dragons in imagination and legends.

The earliest records of real airplanes date back to about 400 B.C., when the ancient Greek philosopher Archimedes described a prototype model of a human-powered flying machine made of wood and feathers. In the 13th century, the Italian Leonardo da Vinci presented his design for a flying machine, but due to the technical limitations of the time, his design was not realized.

It wasn't until the 18th century, when the Frenchman Montsorier brothers invented the hot air balloon, that the first human flight through the air was realized. At the end of the 19th century, the Wright brothers invented airplanes, and in 1903 they successfully conducted the first manned flight experiments.

Aircraft gradually grew, with jets beginning to appear in the 30s and civilian jets such as the Boeing 707 in the 50s. Through decades of technological innovation and continuous development, Napeng modern aircraft has formed various types of models and application fields, which has had a huge impact on modern transportation and international development, and has become one of the most important means of transportation for mankind.

First, the principle of flight of the aircraft.

An airplane is a heavier than air aircraft, and when an airplane flies in the air, it will produce aerodynamic forces acting on the airplane, and the airplane is lifted into the air by aerodynamic force.

Second, the main components and functions of the flight.

So far, with the exception of a few special forms of aircraft, most aircraft have consisted of five main parts: wings, fuselage, tail, landing gear, and power plant.

1.Wings – The main function of a wing is to generate lift to support the aircraft in the air, while also playing a certain stabilizing and operational role. Ailerons and flaps are generally installed on the wings, and the ailerons can be manipulated to make the aircraft roll, and the lift can be increased by lowering the flaps.

Engines, landing gear and fuel tanks can also be installed on the wings. Aircraft for different purposes have different wing shapes and sizes.

2.Fuselage - The main function of the fuselage is to load passengers, passengers, cargo and various equipment, and connect other parts of the aircraft such as wings, tail and engines into a whole.

3.Tail – The tail includes a horizontal tail and a vertical tail. The horizontal tail is composed of a fixed water stabilizer and a movable elevator, and some high-speed aircraft combine the horizontal stabilizer and the elevator into a full-motion flat tail.

The vertical tail includes a fixed vertical stabilizer and movable rudders. The function of the tail is to control the pitch and deflection of the aircraft to ensure that the aircraft can fly smoothly.

4.Landing gear - The landing gear of the aircraft is mostly composed of shock-absorbing struts and wheels, which are used for take-off, landing and taxiing, and supporting the aircraft when taxiing on the ground and parking.

5.Powerplant – The powerplant is mainly used to generate pull and thrust to move the aircraft forward. Secondly, it can also provide power supply for other electrical equipment on the aircraft.

At present, aircraft power units are widely used in aviation piston engines plus propeller thrusters, turbojet engines, turboprop engines and turbofan engines. In addition to the engine itself, the power plant includes a series of systems that ensure the proper functioning of the engine.

In addition to these five main parts, the aircraft is also equipped with various instruments, communication equipment, pilotage equipment, safety equipment and other equipment according to the needs of the aircraft's operation and mission.