The sky is so vast, why should the plane take the route?

Nowadays, people travel more and more means of transportation. Vehicles on land need to obey the traffic rules and wait for the traffic lights. The sky is very vast. Why does the plane fly according to the route? Some students replied that the reason why they fly by route is because there are more and more planes in the sky. Is that really the case? This is only one of the reasons. Let's briefly talk about why the plane should fly according to the route, instead of flying casually.

Limited by navigation technology, the plane can only fly according to the route.

Planes flying in the sky need navigation. In the past, the more mature navigation technologies were VOR navigation technology and inertial navigation technology. The route of an airplane can be simply understood as flying from one navigation station to another. Navigation platform is also called a milestone in the early development of aerospace industry. Pilots aim at landmarks to ensure their correct route. With the development of science and technology, GPS-based navigation equipment has been used. If the ground navigation equipment is subgrade, then GPS is satellite navigation. Nowadays, the regional navigation (RNAV) is based on the update of land-based and satellite-based navigation signals. The inertial navigation system of the aircraft can be continuously positioned, so that it can fly along any desired path, instead of flying from one navigation station to another as in the past, but the route is still fixed.

Fixed routes can save fuel.

A long time ago, scientists tracked their position and speed by launching high-altitude weather balloons. Through a series of observation experiments, scientists found a highway in the sky. If you fly along the expressway, the flight time will be shorter. What is the highway in the sky? In fact, to put it bluntly, there is a strong wind (rapids) in a certain direction in the sky. If you fly with the wind, you will obviously save fuel. According to the fuel consumption of Boeing 777, if you fly on a fixed route, you can save $5600 per flight.

For safety reasons, the plane must have a fixed route.

Although the sky was so vast, there was a tragedy in which two passenger planes collided. On June 30th, 1956, a Lockheed Super Constellation passenger plane of TWA and a DC-7 passenger plane of United Airlines both passed through the famous Grand Canyon on their way to Chicago. However, the two pilots wanted to go together and let the passengers in the cabin enjoy the spectacular scenery of the Grand Canyon, so they both thought of the best route to enjoy the scenery. It is precisely because they all know the scenic route that when two planes flew over the Grand Canyon, they collided because they didn't avoid it in time, and all the passengers on board were killed.

It is not only to prevent the collision of planes with extremely low probability, but also to comply with the regulations of ETOPS, which states that the distance from any point on the flight route to the nearby alternate airport should not exceed 60 minutes, so that the plane can land safely. With the progress of modern technology and the improvement of engine reliability, the limit of 60 minutes has been raised to 120 minutes. In other words, at any point on the flight route, if there is a problem, you must arrive at the alternate airport within 120 minutes. This regulation restricts the aircraft to have a standardized flight route and cannot fly casually.

Other limiting factors

The country enjoys sovereignty over its airspace. When aircraft of any other country enter the airspace of that country, they should abide by the air transit regulations of that country and must fly in accordance with the prescribed routes. There are also natural reasons, such as mountains, rapids in the sky, weather reasons such as thunderstorms and so on.

Of course, there are some other factors, so I won't write them here. I hope you can add something.

It is precisely because of the above factors that the plane must have a standardized route to ensure the safe flight of the whole route.