Why does the plane leave a white track in the sky after it flies?

Condensing end, also known as aircraft cloud or orbital cloud. Finally, the water vapor in the exhaust gas discharged by the plane when it is cold in the air condenses into small ice crystals. Its height is about 35,000 feet to 45,000 feet. From the condensation end, we can judge whether it is a military aircraft or a civil aircraft, and we can also judge the flight altitude, speed and course of the aircraft. In air combat, the combat opportunity avoids this high airspace to avoid being discovered by the enemy.

In fact, a white line in the sky is the tail gas of the plane. The gas from the plane is very hot in the sky. When it meets cold air, it will vaporize quickly, and then it will be cooled by the surrounding cold air immediately, turning into small water droplets and small ice crystals. This is a very simple physical change, and then the sunlight is reflected, and white smoke will appear. In fact, it is as simple as that. I hope to pay attention to and adopt me.

Why do planes sometimes leave a white line when they fly across the sky? The first one is an air show. The second is the white line caused by the release of excess fuel when the plane landed, because it is stipulated that the remaining fuel in the fuel tank cannot exceed the specified value when the plane landed, so as to avoid fire. The water vapor in the wake of an airplane is formed when it is cold.

There are usually two kinds of aircraft wakes. One is that the water produced by fuel combustion condenses into water droplets in high altitude and low temperature air to form wake; Another is that the air contains a lot of water vapor, which condenses into water droplets under the disturbance of the plane, forming a wake.

The geometric scale of wake is much larger than that of aircraft, which will expose the position of aircraft. Therefore, physical/chemical suppression materials can be carried on stealth aircraft, or special aerodynamic structures can be used to reduce the wake.

Of course, there are also trails specially built for celebrations. It is said that one of the formulas is condensed from soybean oil+pigment: D tail gas. Like the smell of winter.

Experience tells us that most smoking planes fly at an altitude of 7 ~ 1 1 km. Although the wake has no influence on normal flight, it will have adverse effects in combat, and it is necessary to avoid exposing one's fighting motivation as much as possible.