Why do airplanes stay in the air for long periods of time?

Originally, humans wanted to be able to fly freely in the air like birds. Later, after repeated practice, the airplane was invented. And the plane can fly because of its wings and engines.

When the airplane is moving, the air above the wing is fast, and the air under the wing is slow, so that an upward lift is generated, and the plane will fly smoothly into the sky. In addition, the engine in the aircraft is connected to the propeller, and the propeller rotates to drive the airflow, and the aircraft can fly in the sky for a long time. Despite the cooperation of various departments, the main thing is that the aircraft has a pair of wings with a special profile shape.

Wing profiles are also known as airfoils. A typical airfoil is convex at the top and flat at the bottom, and is often referred to as streamlined. According to the continuity of the fluid and Bernoulli's theorem, the air flow through the upper surface is squeezed compared to the air far ahead, and the flow velocity accelerates and the pressure decreases, and even suction (negative pressure) is formed, and the flow velocity of the air flowing through the lower surface slows down.

As a result, a pressure difference is formed between the upper and lower wing surfaces. This pressure difference is aerodynamic. According to the law of force decomposition, it is broken down along the direction of flight into upward lift and backward resistance.

The drag is overcome by the thrust provided by the engine. The lift is just enough to overcome its own gravity and lift the aircraft into the air. That's why airplanes fly.

The generation of wing lift mainly depends on the action of the upper surface suction, rather than the effect of the positive pressure on the lower surface, the suction formed on the upper surface of the wing accounts for about 60-80% of the total lift, and the lift formed by the positive pressure on the lower surface only accounts for about 20-40% of the total lift. According to the principle of continuity of air flow and Bernoulli's theorem, the pressure above the wing is smaller than the pressure under the wing, that is, the upward pressure on the lower surface of the wing is greater than the downward pressure on the upper surface of the wing, and this pressure difference is the lift generated by the wing. According to the principle of air, when the aircraft flies, due to the principle of the wing, the air movement above is faster than the air under the wing, the flow of air, the faster the flow of air, the smaller the pressure, so the pressure is formed above and below the wing, so the wing produces upward lift, drags the aircraft in the air, so that the aircraft will not fall, the engine of the aircraft produces forward movement, and the aircraft continues to fly forward in the air.

Why can a tractor climb on the ground?

A brief introduction to the phases of aircraft flight.

In order to complete a flight mission, the aircraft must go through several stages: taxi, take-off, climbing, cruising, descending, and landing. 1. Taxiing and take-off phases.

The aircraft completes all ground services before the flight. Including the completion of passenger boarding, the completion of cargo and baggage loading and unloading, the completion of inspection by the maintenance personnel and the signing of documents to release the aircraft, the acquisition of relevant flight information by the crew from the air traffic control department, the joint verification of personnel by the ground business check-in personnel and the crew, and the correct loading list of the aircraft;

Then, after applying to the air traffic control department and the control tower and getting permission, start the engine on the apron, and arrive at the runway end through the taxiway to prepare for takeoff. It is the taxiing stage, in this stage the aircraft is like a moving vehicle, to operate in accordance with the traffic requirements on the ground, the taxiing section is the time when the aircraft is the heaviest weight, and it is also the time when the pilot makes various preparations and inspections before takeoff, and the same as flying in the air, it also needs to be careful and careful.

2. Climbing stage.

There are two ways, one is to continue to climb at a fixed angle to reach a predetermined height. This has the advantage of saving time, but the power required for the engine is high and the fuel consumption is high. The other is a stepped climb, after the aircraft rises to a certain height in Naziye, it flies horizontally to increase speed, and then climbs to the second altitude, and climbs to a predetermined altitude after several stages, because the lift of the aircraft increases with the increase in speed, and the fuel consumption at the same time makes the weight of the aircraft continue to reduce, so this climb is the most fuel-efficient.

3. Cruising phase.

After the aircraft reaches a predetermined altitude, it maintains a horizontal constant velocity flight state, at which time if there is no influence of weather changes, the pilot can follow the selected route to fly stably at a certain speed and attitude, the aircraft almost does not need to be maneuvered, and the pilot generally only needs to carry out the necessary monitoring. This phase has the lowest flight accident rate.

Aircraft is a common air traffic flight vehicle, which refers to a heavier-than-air aircraft flying in the atmosphere by generating forward thrust or pull force from the power unit and lifting force generated by the fixed wings of the fuselage. Let's take a look at why airplanes can fly in the air for a long time, just for your reference!

The reason why airplanes can fly in the air

Throw the stone upwards, and although the stone is thrown high, it will still fall.

This is because at the beginning, although the force of the stone rising was great, in the blink of an eye the force of the descent became greater.

When the stone rises to its highest point, the rising and descending forces are balanced.

Aircraft can fly in the air by using the principle of equalization of lifting and descending forces.

The plane flies forward, and the wings hit the air, resulting from this'The balance of the lifting and descent forces can keep the aircraft in the air for a long time.

The main advantages of the aircraft

It's fast. Jetliners travel at around 900 kilometers per hour and are highly maneuverable. The flight of the aircraft is not blocked by mountains, rivers, deserts and oceans, and the frequency of flights can be increased at any time according to the number of passengers and goods.

According to ICAO statistics, the average number of fatalities per 100 million passenger kilometers in civil aviation is 1/10th to 1000th of the fatalities in accidents involving ordinary modes of transport, making it a safer mode of transport than trains.

It can make humans feel the feeling of being in the sky!

An aircraft (fixdeinair) is an aircraft with wings, one or more engines, propelled by its own power, and denser than air in space or the atmosphere. If the density of the aircraft is less than air, it is a balloon or airship. Without a power plant, it can only glide in the air, which is called a glider.

If the wing of the aircraft is not fixed and the wing rotation produces lift, this is *** or gyroplane. Fixed-wing aircraft are the most common aircraft type. Power** includes piston engines, turboprops, turbofan engines, or rocket engines, to name a few.

At the beginning of the 20th century, the Wright brothers of the United States made a significant contribution to the history of world aircraft development. In 1997, the first manned flight aircraft under its own power was manufactured, and the test flight was successful. They received the U.S. Congressional Honor Award in 1991.

In the same year, they founded the Wright Aircraft Company. After the invention of the airplane, the airplane has increasingly become an indispensable means of transportation for modern civilization. It profoundly changed and affected people's lives, starting the history of conquering the blue sky.

Why can airplanes fly? Why do airplanes fly? Despite the fit of various components, the main thing is that the aircraft has a pair of wings with a special flat shape.

The typical wing-like convex upper and lower flat, popularly known as streamlined. According to the continuity of the fluid and Bernoulli's theorem, the air flow through the upper leaf is squeezed out relative to the distant air, the flow velocity increases, and the pressure decreases. Even suction (negative pressure) is formed, and the velocity of the air flow through the lower surface is reduced.

Therefore, the pressure difference between the upper and lower wing surfaces is formed. This pressure difference is aerodynamic. According to the law of decomposition of force, it will decompose the upward force and the backward drag force along the direction of flight.

The drag is suppressed by the thrust provided by the engine. Lift is equivalent to overcoming gravity and can propel an airplane into the air. That's why airplanes fly.