Why do airplanes fly in the sky? Why can airplanes fly in the sky?

The reason why airplanes are able to fly in the sky is the result of the interaction of four forces. These four forces are: 1) The thrust of the engine 2) The resistance of the air 3) The gravity of the aircraft itself 4) The lift of the air The take-off of the aircraft depends on the thrust of the engine to produce the speed, and the speed produces the lift through the shape change of the wings, the thrust is greater than the drag, and the lift is greater than the gravity, and the aircraft can take off and climb high.

When the aircraft climbs to the cruising altitude, the small throttle is closed, which is called level flight, at this time, the lift is equal to gravity, and the thrust is equal to the drag, that is, the constant speed flight. Does the plane have to take off against the wind? Of course not"Definitely"Hoo!

The plane can take off against the wind and downwind! According to the theory of flight, the advantages of aircraft taking off against the wind are: 1

Increase the indicated airspeed of the aircraft, so that the aircraft reaches the normal take-off speed in advance (which is equivalent to delaying the stall timing of the aircraft and increasing the steering performance of the aircraft) 2Shorten the runway length required for the aircraft to take off, so that the aircraft can fly off the ground in advance (which is equivalent to reducing the wear and tear of tires and parts) 3In the unlikely event that the aircraft abandons take-off on the runway for any reason, the headwind helps the aircraft to slow down and stop and there is also a longer remaining runway available.

Because there's not nothing in the heavens, there's something that can lift it up.

Under the premise that the aircraft's own engine or the outside world provides power (such as a catapult aircraft during takeoff), relying on the fixed (some aircraft's wings are foldable or variable angle) wings (or similar rotors of aircraft such as ***) generate lift when moving with the air, so as to realize the flight of the aircraft in the sky.

It can be said that if an aircraft wants to fly, it is closely related to the lift generated by the combination of its own power and air.

However, how to make the aircraft fly high and fly smoothly, it still comes down to the performance of the aircraft itself, such as: wings, engines, the advanced degree of various on-board electronic equipment, the overall design of the fuselage and wings, and the weight of the aircraft are all important factors affecting the performance of the aircraft.

Why do airplanes fly? 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.