Air traffic control- How does it keep you safe? by Jorge Ossa

I’ve traveled by air many times, and like most, I never thought twice about what happens after I buckle up and the plane takes off. But have you ever wondered how the pilot knows exactly where we’re going once we’re airborne?

It’s easy to assume they’re in complete control, but when you think about it, especially as you watch dozens, or even hundreds, of planes crisscrossing the sky, it’s hard not to feel uneasy. How do they avoid colliding?

These are common questions for travelers, However, statistics show that flying on a commercial airliner is incredibly safe—safer, in fact, than traveling by motorcycle or car. A key factor contributing to its safety is the air traffic control system.

Control Tower. Olaya Herrera Airport, Medellin, Colombia

Control Tower. Olaya Herrera Airport, Medellin, Colombia

To better understand how air traffic control works, I visited the Control Tower at El Dorado Airport. As the most important airport in Colombia, it is also the busiest in South America and the second busiest in Latin America, with over 35.5 million passengers passing through annually.

I was warmly welcomed by Omar, a tower controller with over a decade of experience. He’s the supervisor for the day and introduces me to the team. The greetings are brief, as each person is focused on their area of responsibility, giving precise instructions to the pilots, outside, dozens of aircraft are taxiing, taking off, and landing, moving in a seemingly choreographed manner.

Guiding Your Flight Safely

The captain, or pilot in command, holds primary responsibility for the safety of the aircraft. However, most of the time the pilot cannot see other planes in the vicinity and may be unaware of their location. To address this, most countries have established an air traffic control system. Ground-based controllers monitor every stage of flights ensuring constant oversight and safety. Omar explains: “Air traffic controllers not only help avoid accidents but also facilitate the seamless movement of planes, ensuring that air traffic flows quickly and orderly”

What all of this means is that while the pilot is tending to his cockpit duties, there are many ground-based eyes and ears following the flight. The pilot regularly talks by radio not only to controllers at the departure and destination airports but also to those at several points in between.

II had the chance to visit Cordova Tower, located at one of the country’s busiest and most important airports. There, I met Cristian, a tower controller with over a decade of experience. He greeted me warmly, then quickly turned back to his headset. “Runway 01, line up and wait,” he said, his eyes flicking between the digital radar screen and the live action unfolding on the tarmac outside.

Cristian’s role? Clearing planes for takeoff and landing. But it’s far from just pushing buttons and rattling off commands. His job is all about multitasking—monitoring taxiing aircraft, coordinating with ground controllers, handling weather updates, and adjusting flight paths as needed. A momentary lapse in focus could have serious consequences.

As we spoke, Cristian pointed out an Airbus on final approach and another waiting to depart. “I have to sequence them so they’re not too close. If someone’s slow on takeoff, I might need to issue a go-around.” He made it sound simple, but the timing was razor sharp. Everything had to move in sync, like gears in a machine.

Cordova Tower. SKRG Rionegro Colombia

El Dorado Tower SKBO, Bogotá Colombia.

Later, I was taken to the nearby Aeronautical Management Center of Colombia—essentially the brain of approach and en-route airspace. This place felt like a whole different world: a massive room filled with huge radar displays. Dozens of controllers sat at individual stations, each responsible for a block of airspace. Here, I met controllers in charge of En- Route Control (or Area Control), who manage aircraft cruising at high altitudes, as well as Approach and Departure Control, which handles planes entering or exiting the airport’s airspace and lines them up safely for arrival or departure.

I was introduced to Ximena, a controller overseeing flights at cruising altitude. She was juggling several planes on her screen, each represented by a symbol and a string of data. I watched as she coordinated a handoff to another sector and issued a vector to an aircraft to avoid oncoming traffic.

“Planes don’t just fly in straight lines,” She told me. “We guide them constantly—adjusting for weather, traffic, spacing.” Every plane is separated by precise vertical and horizontal distances, all calculated in real time.

Aeronautical Management Center of Colombia

In today’s world of high-speed aircraft, monitoring what the pilot can’t yet see is crucial. Santiago Abril an experienced controller explains: “Imagine two commercial jets on a head-on collision course. By the time the pilots spot each other with the naked eye, they might have only seconds to react and avoid a disaster! Preventing that scenario is the responsibility of air traffic control. Long before the pilots are aware of each other, they’ve already received instructions to maintain a safe distance, ensuring a smooth and secure flight”

Tracking Your Flight

How Air traffic controllers track planes along the airways? Before departure, pilots are required to file a flight plan that shows their intended route of flight. The controller has a copy of what is called a flight progress strip. Carlos Torres, an air traffic control chief, explains how this is useful: “There are intersection points on the airways. When a pilot comes over those, he has to report that information to the controller. Then the controller will mark that on his flight strip.” The controller now has a mental picture of the path of that aircraft.

To get those reports, the controller has another tool—the radio. He knows where the plane is, and the pilot receives instructions to help him keep a safe distance from other aircraft. Controllers and pilots usually have a selection of radios and frequencies. Should one fail, they can use another.

What about international flights where different languages are encountered? To prevent the risks of miscommunication, the International Civil Aviation Organization (ICAO) chose English as the universal language of aviation. Additionally, because certain words, letters, and numbers can sound alike when spoken over the radio, air traffic controllers are trained to use standardized phrases and precise pronunciation when giving instructions. To further enhance safety, pilots are required to “read back” specific instructions from controllers, repeating them to ensure the message was received correctly.

During my visit also I learned that radar is a crucial tool used by controllers to manage air traffic. Radio waves emitted by the radar antenna bounce off airplanes, and the reflected signals allow controllers to see the planes as objects, or “targets,” on their radar screens. Many aircraft are equipped with transponders that send an identification signal back to the radar, providing valuable information like the flight number, speed, altitude, and aircraft type.

If the controller needs to adjust the aircraft’s flight path to prevent a collision, they have several options. For instance, they might instruct a pilot to (1) change their heading (or direction), which is known as “vectoring.” Alternatively, they may (2) direct a change in speed if one plane is approaching another too quickly, or they could ask a pilot to (3) change his altitude to create more space between aircraft.

To further enhance safety, many radar systems have built-in alerts that notify the controller of potential dangers. For example, visual and audible alarms will trigger if two aircraft are on a collision course, or if an airplane is getting too close to the ground. These systems are critical in maintaining a safe and efficient flow of air traffic.

The Priority: Keeping You Safe

One thing that struck me was the sheer coordination involved. Tower, ground, approach, center—they’re all talking to each other constantly, handing aircraft off like relay batons. It’s invisible to passengers, but without it, the sky would be chaos. No wonder accident rates for commercial aircraft are very low!

Despite the complexity, commercial aviation is one of the safest modes of transportation— thanks largely to ATC. According to the International Civil Aviation Organization (ICAO), over 100,000 commercial flights operate safely every day. Major incidents involving ATC failures are extraordinarily rare.

By the time I left, I had a new appreciation for the people behind the scenes. Air traffic controllers don’t get applause when we land safely. But they work with an intensity and precision that literally saves lives every day.

On my flight back home, I got the incredible chance to sit in the cockpit of the plane. As we soared through the sky, the Captain Felipe Echeverri shared an important insight: “Without air traffic control, we simply could not reach our destination safely” Hearing that firsthand really drove home how vital the coordination between pilots and air traffic controllers is—without it, keeping flights on track and out of danger in the busy skies would be nearly impossible.

As I glanced out the airplane window at 21,000 feet, it was easy to marvel at the view and forget about the invisible infrastructure keeping us safe. But in that moment, I couldn’t help but think about the air traffic controllers—silent sentinels of the skies. With their skill, technology, and unwavering focus, they ensure that every journey ends safely on solid ground.

If you’re a passenger, there’s really no reason to feel uneasy. The next time you’re on a flight, remember that the eyes and ears of air traffic control are always there, working behind the scenes for your safety.

And when you feel the smooth landing on the runway, take a moment to appreciate that it’s not just the pilot who made it possible—it’s the entire team on the ground, ensuring we arrive safely, every time.