Aircraft refers to aircraft heavier than air. An airplane flight is the result of the action of the lifting force that occurs when air flows towards the wing. It is rotated at a precisely calculated angle and has an aerodynamic shape, due to which, at a certain speed, it begins to tend upwards, as the pilots say - “it gets into the air”.
The aircraft is accelerated and the engines maintain its speed. Jet propels the aircraft forward due to the combustion of kerosene and the flow of gases escaping from the nozzle with great force. Screw engines “pull” the plane with them.
How does lift come about?
The wing of modern aircraft is a static structure and in itself cannot independently create lift. The ability to raise a multi-ton machine into the air arises only after the translational movement (acceleration) of the aircraft using a power plant. In this case, the wing, set at an acute angle to the direction of the air flow, creates a different pressure: it will be less above the iron plate, and more at the bottom of the product. It is the pressure difference that leads to the emergence of aerodynamic forces that contribute to the climb.
The lifting power of aircraft consists of the following factors:
- Angle of attack
- Asymmetric wing profile
The inclination of the metal plate (wing) to the air flow is called the angle of attack.Typically, when raising the aircraft, the mentioned value does not exceed 3-5 °, which is enough to take off most models of aircraft. The fact is that the wing design has undergone major changes since the creation of the first aircraft and today is an asymmetric profile with a more convex top sheet of metal. The bottom sheet of the product is characterized by a flat surface for almost unhindered passage of air flows.
Schematically, the process of formation of lifting force looks like this: the upper jets of air need to go a greater way (due to the convex shape of the wing) than the lower ones, while the amount of air behind the plate should remain the same. As a result, the upper trickles will move faster, creating, according to the Bernoulli equation, a region of reduced pressure. The direct difference in pressure above and below the wing, coupled with the operation of the engines, helps the aircraft gain the required altitude. It should be remembered that the value of the angle of attack should not exceed a critical point, otherwise the lifting force will fall.
How to fly a plane?
The wing and engines are not enough for a controlled, safe and comfortable flight. The aircraft needs to be controlled, while control accuracy is most needed during landing. Pilots call the landing a controlled fall - the speed of the aircraft decreases so that it begins to lose altitude. At a certain speed, this fall can be very smooth, resulting in the wheels touching the strip chassis softly.
Driving an airplane is completely different from driving a car. The pilot's helm is designed to deflect up and down and create a roll. “For yourself” is a climb. “From myself” is a decline, a dive. In order to turn, change course, you need to press one of the pedals and tilt the plane in the direction of rotation ... By the way, in the language of pilots this is called a “turn” or “turn”.
To turn and stabilize the flight, a vertical keel is located in the tail of the aircraft. And the small “wings” below and above it are horizontal stabilizers that do not allow a huge machine to rise and fall uncontrollably. On the stabilizers for control there are moving planes - elevators.
To control the engines between the seats of the pilots there are levers - during take-off they are transferred fully forward, to maximum thrust, this is the take-off mode necessary for gaining take-off speed. When landing, the levers are retracted fully back to the minimum traction mode.
Many passengers watch with interest how, before landing, the back of the huge wing suddenly drops down. These are flaps, the “mechanization” of the wing, which performs several tasks. When lowering, fully released mechanization slows down the aircraft to prevent it from accelerating too much. When landing, when the speed is very low, the flaps create additional lifting force for a smooth loss of height. When taking off, they help the main wing keep the car in the air.
Why not be afraid in flight?
There are several moments of flight that can scare the passenger - this is turbulence, passing through the clouds and clearly visible vibrations of the wing consoles. But this is absolutely not dangerous - the design of the aircraft is designed for enormous loads, much more than those that arise with the "chatter". The jerking of the consoles should be treated calmly - this is permissible design flexibility, and flight in the clouds is provided by instruments.
The plane is not afraid of a lightning strike. An atmospheric discharge flows only along its surface, so some devices may turn off for a minute. They turn on again, and the flight continues as usual. And trouble in flight can cause birds, thunderclouds, they are called "fronts", and a strong crosswind during landing.
A bird falling into the engine stops it, in the thunderclouds that the liners are trying to get around, very powerful air currents that can tip the plane, and a side wind blows the plane off the strip.
Modern liners are real airships, stable and fully automated. They fly along strictly defined routes, “corridors” of flight, under constant control from the ground, and in order for the planes to disperse, there are echelons — given for the flight altitude. They never intersect. But the organization of flights and air traffic control is a special, very large and interesting topic.
