This is a picture that captures airplanes while they are in the air. There are many airplanes flying in the air. Isn’t it amazing? That begs the question,
“How on earth do airplanes not crash into each other in the air?”
There are no traffic lights and lanes, so how do airplanes not crash into each other? If you fly without traffic lights and lanes, doesn’t it seem as though you’ll get hit?
However, there is no need to worry. There are invisible routes in the air. In fact, airplanes are flying safely along airways, also known as “air routes.”
What is an air route, and how are they created? Today, we will delve into air routes, the secret routes of the air!
Roads and Air Routes have a Few Similarities!
Roads refer to the paths along which cars travel, and air routes are paths along which airplanes fly. But did you know that they have some similarities?
1) Like roads, air routes have unique identifiers, as well as two-way and one-way routes.
2) Like vehicles must drive on the road, airplanes must fly along designated air routes.
3) Like vehicles must pay tolls to drive on the highway, airplanes must pay “overflight fees” in the air.
Air routes don’t look much different from roads, right? But they have some differences as well! The biggest difference is that there are no physical signs in the air.
If that’s the case, how can airplanes fly along air routes without any signs?
"Waypoint," a Sign in the Air
Although invisible, air routes have their own signs! This is because they have waypoints, or virtual points on the map. Waypoints have an important presence, even though they are not visible! In the end, air routes are paths that connect these waypoints.
Waypoints are coordinates consisting of latitude and longitude designated by the International Civil Aviation Organization (ICAO). There is a large number of waypoints on the earth, and air routes are the lines that connect these points. And airplanes fly safely along their designated air routes.
The ICAO divides the earth into 8 regions: Pacific, North American, Caribbean, South American, North Atlantic, European, Africa-Indian Ocean, Middle East, and Asia. Considering the territory and flight capabilities of member states, the ICAO further divides each region into flight information regions (FIR).
Korea designates air routes for civil aircrafts in the Incheon FIR of the Middle East and Asia Regions and provides necessary flight information. In Incheon FIR, there are 11 international air routes indicated by A, B, G, and R, and 5 Korean air routes indicated by V and W. Incheon Air Traffic Control Regional Office is in charge of traffic control for all civil aircrafts!
Most waypoints are named by the country that has jurisdiction over it. There are also some funny names that are unique to a few countries. For instance, Korea has waypoints named GUKSU, DOKDO, and JADOO. Aren’t the air routes made by these unique waypoints quite cool?
▲Waypoint “DOKDO” and nearby waypoints (source: https://opennav.com/)
Leaving Along One Route and Returning Along Another Why Air Routes are Different When Leaving and Returning
Let’s talk about driving to a destination. There are many routes you can take, and the route you take will be different depending on the road conditions or travel purpose, right? Airplanes also have different air routes between origins and destinations.
There are many reasons why there are different air routes for leaving and arriving. Here are the main factors!
1) Use of a one-way air route
I told you that air routes are categorized into one-way and two-way routes. If the air route you take when leaving is designated as a one-way for safety, you have to use a different air route when returning, right?
2) Need for safety precautions
If there is a problem with the airplane, there must be an airport close by at which it can land. For this reason, airplanes cannot go straight to its destination, and instead fly along a route where there are various airports.
3) Different relationships between countries
Air routes may vary depending on the relationship between countries. You cannot fly over a country without obtaining permission. If you fly over a country after obtaining permission, you have to pay the country “overflight fees.” Isn’t it surprising that there are also tolls in the air?
4) Use of a “wind stream”
Like currents in the sea, there are also wind flows in the air. These are also known as “jet streams.” If you fly along the jet stream, you can get to your destination more quickly. It is difficult to fly against a jet stream it as the wind power is colossal.
Furthermore, keep in mind that air routes vary depending on the season or type and performance of the aircraft!
Why is there a time gap when you travel between the same places? Routes between Incheon and LA are not the same when leaving and returning. Many airplanes use jet stream air routes when they go to the US and great circle or Arctic air routes when they come back. When they come back, they go around the jet stream, which inevitably takes more time!
How Do Airplanes Not Crash into Each Other on the Same Air Route?
I know there are air routes, but what if multiple airplanes are flying along the same air route? “Distancing” is a way to safely fly along the same air route. This is the secret to how airplanes can fly safely without crashing into each other!
Airplanes fly at a “safe distance” between each other. Like vehicles driving keeping a distance from other vehicles, airplanes keep a distance from other airplanes both horizontally and vertically. The flight altitude applies differently depending on the airplane’s flying direction. Usually, airplanes flying east maintain odd-numbered altitudes and airplanes flying west maintain even-numbered altitudes.
There are some other methods that supplement safe distancing and help airplanes fly safely. These are called “instrument flight rules” and “TCAS!” Let’s talk about instrument flight rules first, shall we?
There are “visual flight rules,” by which a pilot flies an airplane based on the horizon in weather conditions clear enough to allow the pilot to see where the aircraft is going and “instrument flight rules,” which rely on the instrument panel regardless of weather conditions. Instrument flight rules must be followed in air routes, and communication between pilots and air traffic controllers is extremely important. When the air traffic controller informs the pilot of the airplane’s speed or distance and altitude from nearby airplanes, the pilot changes its altitude or direction to avoid any obstacles or crashes with other airplanes!
Traffic collision avoidance system (TCAS) also helps airplanes fly safely. TCAS is a system that uses a radar to inform the pilot of the airplane’s location. With TCAS, the pilot can know the locations of and distances between nearby airplanes without the air traffic controller. So, you don’t have to worry about the safety of airplanes, right?
Today, we have looked at air routes, the invisible routes of the air. Isn’t it amazing that there are also routes in the air that allow airplanes to fly safely? But this is not the end! Right now, many efforts are being made around the world to find new air routes.
Incheon Airport will pave its own routes so that it can become a safer and more convenient airport.