I am about to board a flight from Madrid to Zurich, and I admit that, for the first time in my life, I would like to experience turbulence. It is also the first time I will be traveling in the cockpit, alongside the pilots.
The reason? Various scientific studies suggest that, due to the effects of climate change on the atmosphere, clear-air turbulence is increasing: those that occur in clear skies and are difficult to detect in advance, unlike those associated with clouds and storms (convective turbulence), or those that can occur when flying over large mountain ranges (orographic).
In addition to these studies, news of incidents on flights from different airlines that resulted in injuries and scenes of panic have added to the growing concern. The latest incident occurred on September 21 during the Vitoria-Palma de Mallorca route and left two flight attendants injured. However, the most impactful incident took place on May 21, 2024, on a flight from London to Singapore: it experienced severe turbulence that caused a hundred injuries and the death of a 73-year-old passenger from a heart attack with a history of heart problems. Just five weeks later, another flight between Madrid and Montevideo reported six serious injuries and around thirty minor injuries.
These are examples of incidents that have gone viral and have increased anxiety among those who fear flying, especially now that we are flying more than ever. Last year, global passenger air traffic grew by 10.4% compared to 2023, and by 3.8% compared to pre-pandemic levels. In total, 40.6 million journeys were made.
Do turbulence represent a real danger to flight safety? Has their frequency increased, or are we just more aware of them due to social media? Are these incidents fueling a fear of flying? Four Iberia pilots will explain to us in the middle of a flight on an Airbus A320 how they face these episodes and what tools they have to deal with turbulence - which can be light, moderate, or severe - and if they have noticed the increase in frequency mentioned in those studies.
The most cited study was published in the journal Geophysical Research Letters in 2023 and was conducted by scientists from the University of Reading and the UK Met Office. One of its authors, Paul D. Williams, had previously published in 2013 and 2017 other works on the subject, in which, based on climate modeling studies, he concluded that clear-air turbulence on transatlantic routes will significantly increase in the future as the climate changes, linking it to the increase in atmospheric CO2 concentration.
In the 2023 study, they analyzed 40 years of data and concluded that between 1979 and 2020 there was a significant and widespread increase in that turbulence, especially in the North Atlantic. They recorded a 55% increase in severe turbulence, 37% in moderate turbulence, and 17% in light turbulence. Europe, the Middle East, and the South Atlantic also showed a significant increase. And the forecasts are not more encouraging: according to Williams, climate models indicate that turbulence will become more frequent, and those capable of causing injuries could even "double or triple."
According to this team, the reason is the alteration of atmospheric dynamics due to the increase in global temperatures and the modification of jet streams - or jet streams, which are fast-moving air currents in the upper atmosphere, at the same altitude at which commercial aircraft fly. These air highways form due to the temperature difference between the tropics (very hot air) and the poles (very cold air) and flow around the planet from west to east. In a simplified way, climate change would be increasing the temperature difference between warm and cold air masses that collide to form the jet stream, making it less stable and causing more turbulence.
Flight plan map, with the predicted turbulence areas for the Madrid-Zurich route that day.
On the outbound journey, we will fly with Rafael San Julián (51 years old), a captain with 26 years of experience, and with the first officer, Manuel López de Lerma (35 years old), a co-pilot for six years. On the return flight, the aircraft will be under the command of Captain Fernando Javier Rodríguez (53 years old), with 35 years of experience - seven of them in the military - and co-pilot Marina Ibarrondo (27 years old), with three years of experience.
We meet around eight in the morning with Rafael San Julián and Manuel López de Lerma at the Crew Office of Terminal 4 of Barajas Airport, where they gather to prepare for the flight: "Pilots receive the flight dispatch, which is the plan we will follow, with all the information about the route, the altitudes at which we will fly, the predicted turbulence at each point, and the weather both in Madrid and at the destination, and at alternate airports. The co-pilot and I evaluate all the information," says San Julián, who has already reviewed it at home.
It is September 22, and the front that caused very heavy rains in Catalonia the night before is heading towards Italy. "Today we have a fairly strong jet stream, which is associated with a turbulence zone," he explains. "Jet streams move the air around, and that's why there are turbulence zones associated with the jet stream," he adds while showing us the map. "This indicates that we may encounter some moderate turbulence from the Pyrenees to Switzerland, practically throughout that area, starting around 45 minutes into the flight. In Zurich, there are low clouds and rain, and we may encounter some icing - ice formation - especially during descent," he anticipates. "The calmest days, without a breath of wind and clear skies, we call them sunny and fly days. Today is not one of those days, but it's a normal day," he says reassuringly.
"Since the predicted turbulence zone today is very extensive, we cannot avoid it, so we have loaded a bit more fuel in case a descent is necessary. The closer to the ground you fly, the more fuel is consumed due to the higher air density," affirms the captain. Next, during the briefing with his crew, he explains all aspects of the flight, both safety and onboard service planning. After the meeting, we head to the plane.
While passengers board, the pilots continue with preparations in the cockpit: "The tailwind we will have will make us go fast: the flight will last one hour and 43 minutes," details López de Lerma. Shortly after takeoff, he comments that we are experiencing wake turbulence, caused by the preceding aircraft, although it is barely noticeable. "When flying, you move the air; that's why the aircraft that took off before us has moved us a bit."
On the tablet they carry on board, they have the eWas tool, which provides meteorological information based on satellite observations and numerical prediction models: "To identify areas where there may be turbulence, we rely on these models and reports from other pilots we receive during the flight," says López de Lerma.
They also have a weather radar: "It helps me detect clouds, which are associated with a certain level of turbulence depending on the type of cloud. The densest and most compact clouds can contain a lot of ice and are the ones we should avoid. That's why some clouds we can fly through and others we go around. Another essential tool is your eyes: I know that clouds can move the plane more or less thanks to my experience and knowledge of meteorology," explains San Julián.
The tablet that the pilots carry on board with the eWas system to consult the weather and other parameters for their flight
The tablet that the pilots carry on board with the eWas system to consult the weather and other parameters for their flight
Before reaching the Pyrenees, we encountered clear air turbulence, and the captain activated his seatbelt signal: "Clear air turbulence is mainly caused by changes in wind direction or intensity," explains the captain. "I compare them to singles on the highway. People get scared, but it's something completely normal that we have completely under control, and it doesn't affect the safety of the flight at all," adds López de Lerma.
We chose this flight to Zurich because we'll be passing through the Alps, one of the areas in Europe—along with the Pyrenees—where orographic turbulence can occur: "When you fly near a mountain range, it's more likely to occur, but it depends on the position of the plane, the mountain, and the wind. I've taken countless flights over the Pyrenees or the Alps, and on many of them, there hasn't been any turbulence while flying over them," says San Julián.
This time, they expected some orographic turbulence on the outbound flight, but we won't have it; nor will we on the return flight. "In the case of the Andes, there are special procedures for crossing that mountain range. We collect all the cars, and both passengers and crew remain seated with their seatbelts fastened because our experience tells us that if there is turbulence there, it's quite intense. We prefer prevention to cure and we always try to anticipate what might happen."
We landed in the rain, and Rafael San Julián takes stock: The turbulence associated with the jet stream was less than expected. "We prepare for the worst and hope for the best," he summarizes.
On the return flight, from Zurich to Madrid, the crew changes. "The forecast is for a route with a headwind and a jet stream that could generate some moderate turbulence from one hour into the flight, and until approximately one and a half hours," explains Captain Fernando Javier Rodríguez.
However, turbulence appears earlier, and the captain consults with flight control in France about the reports available at a higher altitude to try to mitigate it. He receives clearance, and we climb from 35,000 to 37,000 feet. The turbulence ceases, and at that altitude, they will use less fuel. "There are many types of turbulence and many ways to mitigate it. In addition to forecasts, we pilots are trained for it; Aircraft are also capable of detecting them directly and indirectly. There are procedures to avoid entering these areas, and if you do enter, to mitigate them," he explains. Even so, he clarifies: "It's not about avoiding turbulence at all costs, just as you can't expect to navigate the sea hoping there are no waves. There are types of turbulence that can be managed; severe turbulence must be avoided, and this is very rare."
The pilot shows us the on-board manual, which details the procedure for severe turbulence, with tables indicating, depending on the aircraft's weight and altitude, how to adjust power to fly at the optimal speed to cross this unstable area. "In the 35 years I've been flying, I've experienced severe turbulence in a very short period of time, and without consequences for the aircraft or injuries," says Fernando Javier Rodríguez.
Rafael San Julián recalls that in his 26-year career, he only experienced one episode of moderate-severe turbulence while crossing the Pyrenees, also without injuries or damage to the aircraft: "Thanks to mathematical models, we know where severe turbulence is likely to occur. We always look for the most efficient route possible—the one that allows us to arrive first and with the lowest fuel consumption—while avoiding areas of storms and severe turbulence. "Iberia plans its routes with safety as a priority, even if that means they are less economical because we have to take a detour," emphasizes San Julián.
Have pilots noticed the increase in clear-air turbulence reported in scientific studies in recent years? "Absolutely not, I have not noticed that increase," assures Rafael San Julián. "These are interesting studies, but from my professional perspective, there are things I question. They say there have been more events in the North Atlantic and North America, which are the regions with the highest number of flights. It's logical that where there are more flights, more events are recorded, but that's because the number of observers is greater and there's more technology. I don't deny that the frequency may have increased, but I think more is being observed. And although there are 40 years of satellite data, the methodology used is inconsistent, and the authors themselves acknowledge that there is a lack of data," he argues.
"Incidents involving turbulence have always occurred, and they continue to occur, of course. And as the number of flights increases, it's logical that the number will increase," says San Julián. "I have a friend who is afraid of flying and calls me every time she has to take a plane and says, 'There's more and more news about turbulence.' And I reply, 'That's different from it happening more and more. It's just that we hear about it more and more. I want to demystify it: it's not that there are more and more turbulence incidents, but that they are becoming more and more widely reported. Today, everyone carries a camera phone, and social media amplifies any event. Before, there could be an incident in Bangladesh and you wouldn't even notice; now you do."
Captain Perico Durán (46 years old), who has been a pilot for 25 years, agrees. "I really haven't noticed an increase in clear-air turbulence. There are few cases of severe turbulence; I've had moderate turbulence, which is quite uncomfortable," he says in a telephone interview.
Fernando Javier Rodríguez has also not noticed "a significant increase "or" about turbulence in clear air: "What does happen sometimes is turbulence associated with the heating of the air mass." During the descent to Madrid airport we experienced it: "When the air heats up, it loses density and tends to rise in a disorderly manner. If you hit an updraft, you move with it, and the warmer the air mass, the stronger the updraft, which is why it tends to be stronger in the afternoons," explains this commander.
Throughout the history of aviation, deaths caused by turbulence have been very rare. There are no official figures, but besides the passenger who died of a heart attack last year, an incident on a flight in Japan in 1997 caused the only other fatality attributed exclusively to turbulence in recent decades.
Donald Eick, a meteorologist with the US National Transportation Safety Board (NTSB), compiled a study of accidents in which there were fatalities associated with turbulence between the 1960s and 1990s, when airplanes did not have the current technologies and safety measures, nor were the investigations carried out as exhaustively as they are today. Among those accidents, there were two in which an in-flight breakup occurred: one in 1966, near Mount Fuji (Japan), orographic turbulence, and another in 1968, in Pedro Bay (Alaska), due to severe turbulence.
Most of those injured by turbulence are crew members or passengers who were not wearing seatbelts or were standing. According to NTSB data, collected by the Federal Aviation Administration (FAA), at least 206 people—40 passengers and 166 crew members—were seriously injured by turbulence in the US between 2009 and 2024.
On the other hand, between 2014 and 2018, a total of 240 severe turbulence events were reported to the aircraft manufacturer Airbus: injuries occurred on 30% of affected long-haul flights, while injuries occurred on 12% of short-haul flights with severe turbulence. On long-haul flights, passengers tend to spend more time unbuckled, either to go to the bathroom or walk around the cabin, which could explain why injuries are more frequent on long flights, according to the company.
"High-profile incidents involving passenger injuries during severe turbulence highlight the risks associated with this phenomenon. Fortunately, these serious incidents are rare, and millions of flights are completed without incident each year," says Stuart Fox, director of flight and technical operations and spokesperson for the International Air Transport Association (IATA). However, he emphasizes, "the aviation community is aware that, in these rare cases, the risks can be significant for both passengers and crew." In addition to injuries, "delays, diversions, and aircraft damage occur."
For this reason, in 2018, IATA launched the Turbulence Aware platform, aimed at mitigating the impact of clear-air turbulence. This tool compiles and shares real-time data sent by 2,800 aircraft from 29 airlines, including Air France and Etihad. Currently, no Spanish airlines are part of the program, although, according to Fox, discussions are underway. In the first six months of 2025, participating airlines generated 24.8 million turbulence reports, a 23% increase compared to the same period in 2024 (when five fewer airlines reported).
"Although it's not a foolproof system, real-time data sharing contributes to safer and more comfortable flights, as it allows pilots to deviate from their route, descend, or ascend to more stable altitudes. And if that's not possible, they can activate seatbelt reminders or delay meal service," says Fox. He also emphasizes that citizens "are paying attention to these rare incidents." A survey conducted by IATA in April revealed that 54% of travelers are more concerned about turbulence than last year.
Ignacio Gallego-Marcos has also noted a growing interest and concern about turbulence. This industrial engineer specializing in computational fluid mechanics and based in Sweden has created Turbli, an online turbulence prediction tool. "On one of my flights from Madrid to Stockholm, I wanted to check the turbulence forecast and assumed there would be a tool, but it didn't exist, so I got the urge to create it," he says. He launched it in 2020 and today has 350,000 monthly users. His website also compiles information on this topic, such as research on the increase in turbulence due to climate change: "There are several studies that show that turbulence will increase over the years, although there is uncertainty about how this will develop," says Gallego-Marcos.
Turbli also publishes rankings of the routes that have experienced the most turbulence over the past year. In 2024, the Mendoza-Santiago de Chile, Córdoba-Santiago de Chile, and Mendoza-Salta routes topped the world list. By continent, Nice-Geneva, Nice-Zurich, and Milan-Zurich stood out in Europe. In North America, the Albuquerque-Denver flight was the most popular; in Asia, the Kathmandu-Lhasa flight; and in Africa, the Durban-Johannesburg flight, according to this website.
"I've never been afraid of flying; I created this tool with users who were curious about the topic in mind. But most of those who use it are afraid and consult it to learn about their flight expectations," says this engineer, who has published a book on overcoming fear in collaboration with psychiatrist Mark Silvert: Overcome Your Fear of Flying.
Captain Rafael San Julián is part of Iberia's program aimed at combating the fear of flying: "We try to demystify certain ideas about aviation. When things are explained to you and you understand the reasons, it's easier to defuse fear," he reflects. From his experience, "there are different types of fear that come together in an airplane. Some people believe they are afraid of flying but are actually claustrophobic, and when the plane moves, their perception of turbulence intensifies because they are on alert. There are also those who are afraid of losing "He's in control, and when he's in a plane, he feels like nothing depends on him."
According to this captain, "turbulence is something we should normalize. The main fear is that the plane won't be able to handle it and a catastrophe occurs, but planes are designed to withstand it without a doubt. Even so, I think the idea that resonates most with people is that I'm the first one who wants to go home and that, under no circumstances, I'm going to expose us to a risky situation," argues this Iberia pilot.
"Turbulence is the fear par excellence among those who are afraid of flying, and it's the one they should have the least fear. "It often stems from ignorance, and knowledge is a powerful tool to combat it," notes Commander Perico Durán, who has turned the Instagram account he opened to share his passion for aviation into a forum where he debunks misconceptions, many of them related to turbulence.
He has also launched an online course on how to overcome the fear of flying, offering practical strategies for overcoming it. "I was surprised that it's so widespread. The spectrum is very broad, from people who get a little nervous to limiting phobias, like the case of a girl who would vomit if she saw a plane flying," he notes. The pilot assures that it can be overcome and it's not very difficult: "You overcome it by relying on two pillars: knowledge and therapy. If you have a limiting phobia, it's not enough to read a book or take a course; "You should go to a therapist," he suggests.
Perico Durán believes that the way these incidents are sometimes reported contributes to erroneous beliefs. One of the most widespread is the fear that the plane could fall into an air gap. "There are no air gaps in the atmosphere. When a news report says the plane descended 4,000 meters in four minutes, some people think it went into free fall. And what happens is that, faced with moderate or severe turbulence, you ask flight control to give you another flight altitude and you descend voluntarily. At most, in the most extreme cases, you lose a few dozen meters."
He also clarifies that after an incident involving injuries, the captain usually lands at an unscheduled airport, "but he does so so that medical attention can be provided as quickly as possible, not because the plane cannot continue flying." Furthermore, he warns, "the images of the cockpit, with fallen objects and 200 loose masks, can give the impression that the passengers have had to use them." However, they can be released even if the oxygen system has not been activated, since the mechanism that releases them is very sensitive to pressure changes.
Another common fear is that turbulence could break the plane's wings or make it unmanageable: "Although it may feel uncomfortable or scary inside the cabin, it doesn't require any effort or pose a real danger to the plane because it's designed to withstand them," Durán emphasizes. According to him, regulations require aircraft to be certified to withstand forces of up to 3.8G without damage, and up to 5.7G with damage that allows them to continue flying. As a reference, light turbulence is up to 0.5G; moderate turbulence is up to 1G; and severe turbulence reaches 1.5G. The record turbulence measured was 2.5G and was experienced by a NASA plane while passing through the eye of a hurricane," he explains.
Airbus sources explain that their aircraft "are designed to withstand loads far greater than those produced in the most extreme natural conditions. This includes the use of flexible composite materials in the most modern models, such as the A350, capable of absorbing some of the impact of turbulence. This model, the A380, and much of the A320 fleet, the aircraft manufacturer explains, "are equipped with advanced weather radars. In addition, the autopilot systems are designed to cope with turbulence. When activated, it makes the necessary corrections to maintain the plane's stability, often more effectively than a human pilot."
Furthermore, as Ignacio Gallego-Marcos points out, the plane's design can influence how turbulence is perceived inside the passenger cabin. It depends on a parameter called wing loading, which is the total weight of the plane divided by the total wing surface area: "That's why the best option for turbulence is an airplane that weighs a lot but has very short wings," explains this engineer.
"The reports we receive from other pilots indicate who reported the turbulence, because a small plane reporting it isn't the same as one of the largest planes we have at Iberia, like the A350, which is more difficult to move," explains Rafael San Julián. According to this captain, perception varies even among aviation professionals: "Sometimes I've flown through areas where another pilot had just reported moderate turbulence, and for me, it was... "light."
If you've thought that some captains are more inclined than others to activate the seatbelt sign during a flight, you're right: "There are definitely differences. Some use it quickly and others less quickly, although we all take safety very seriously," acknowledges Rafael San Julián. "My crew's perception of how turbulence feels in the passenger cabin helps me a lot. I think I fasten seatbelts sparingly; I don't want to leave people without access to the bathroom any longer than necessary." And what I do is warn them when we're going to encounter expected turbulence because the scariest thing is running into something they didn't expect." During our trip to Switzerland, flight attendant Patricia Hernando told the captain that a passenger had confessed to her that she was afraid of flying, and San Julián briefly left the cockpit during the flight to check on her.
For his part, Durán admits to being "excessively cautious because turbulence isn't dangerous for the plane, but someone could get hurt." Therefore, he suggests "interpreting the seatbelt sign to know whether you can get up or not. As a general rule, always wear your seatbelt."