Light turbulence includes slight changes in altitude with minor effects on a plane and its passengers.
Moderate
Moderate turbulence will also have changes in altitude, and the effects felt will be more intense.
The plane may also experience differences in attitude, but the pilot will remain in control of the aircraft.
Severe
Severe turbulence involves large, abrupt changes in altitude and/or attitude.
A pilot may momentarily lose control of the aircraft during severe turbulence, and some objects may fly in the cabin. Yet, there will be minor damage to the aircraft overall.
Extreme
Extreme turbulence can cause structural damage to the aircraft and possibly result in loss of control.
Clear Air Turbulence (CAT) suddenly occurs in clear, cloudless, weather.
CAT causes an aircraft to violently shake, but it’s usually not dangerous.
CAT mostly happens outside of clouds at altitudes above 15,000 feet MSL, and is caused by strong winds from the jet streams.
Thermal Turbulence
Thermal turbulence is caused by warm air rising from the surface or cold air moving over warmer ground.
The rising currents result in compensating slower downward currents, which results in turbulence.
These thermal currents prevent the air from flowing normally.
Temperature Inversion Turbulence
Turbulence inversion happens when a layer of calm air rises above turbulent air.
The turbulent air brings down warm air and cools the upper part of the warm air.
The calm air on the top eventually becomes warmer, resulting in a temperature inversion.
Although temperature inversions produce a stable atmosphere, there is often turbulence between the turbulent layer and the outside atmosphere’s boundary.
Mechanical Turbulence
Mechanical turbulence is caused by wind flow around irregular terrain or artificial obstructions, like tall buildings.
Horizontally flowing wind is disturbed by these obstructions and transformed into irregular wind movements that cause turbulence.
Frontal Turbulence
Frontal turbulence is either caused by rising warm air or abrupt shifts between warm and cold air.
Fast-moving cold winds cause the worst frontal turbulence.
Frontal turbulence can be especially severe if the air is moist and causes thunderstorms.
Mountain Wave Turbulence
Airflow over the mountain results in the air currents oscillating between altitudes. This oscillation causes turbulence that extends for hundreds of miles down the mountain.
Thunderstorm Turbulence
Although storm clouds are the only visible part of a thunderstorm, the turbulence caused by thunderstorms extends far outside the storms.
It’s even possible for thunderstorms to generate severe turbulence as far as 15 to 30 miles from a storm cloud.
Wake Turbulence
Wake turbulence forms behind aircraft – it occurs because of atmosphere disturbances.
The most important components of wake turbulence are wingtip vortices and jetwash.
Although wake turbulence can be very dangerous, it normally only lasts for only a short duration, and smaller planes are much more greatly affected.
Why Turbulence Occurs
Turbulence is caused by irregular or violent wind, which causes planes to bounce around.
Turbulence is comparable to when two ocean waves meet.
When two large waves collide, they create even larger waves, causing disturbances for ships.
Like ocean water, air is always in motion, and planes depend on the air’s motion to fly. Aircraft depend on airflow above and below the plane’s wings. When irregularities disrupt these airflows, the result is turbulence.
As explained above, there are different types of turbulence caused by different factors like rising temperatures, thunderstorms, and mechanical failures.
Turbulence Doesn’t Last Long
On average, turbulence lasts between 10 and 15 minutes, but it may last longer depending on the cause of turbulence.
Turbulence can often feel like it lasts an eternity because of its intensity, but it will almost never exceed 20 minutes.
Planes Can Take a Lot of Turbulence
Turbulence can rapidly change a plane’s altitude and make it feel like the plane is falling.
Most commercial planes fly at an altitude of 30,000 feet or higher, so the decline in altitude is minimal.
Nowadays, turbulence rarely causes plane crashes because modern planes are engineered to withstand immense trauma.
In fact, modern airplanes can withstand 1.5x force on their airframes, as well as most changes in atmospheric conditions.
The most dangerous type of turbulence is wake turbulence, which can cause airplanes to roll mid-air, which can damage the aircraft.
Yet, turbulence is largely not dangerous for planes and won’t cause permanent harm.
Planes Have Crashed Due to Turbulence Though
The Federal Aviation Administration (FAA) reports 234 turbulence accidents between 1980 and 2008.
These incidents include 298 injuries and three fatalities, of which 2 were caused by passengers not wearing seatbelts.
Most turbulence accidents don’t result in plane crashes or fatalities, but there are notable exceptions.
For example, American Airlines Flight 587 crashed in New York City in 2001 due to wake turbulence from another plane.
Pilots Cab Avoid Turbulence
Pilots can avoid turbulence, and they’re trained to do so, too.
Pilots rely on weather data to predict areas where turbulence is high, and they avoid those routes.
Most types of turbulence are easy to predict because it’s caused by predictable weather.
The most difficult type of turbulence to avoid is clear air turbulence.
How to Deal With Turbulence Anxiety
To deal with turbulence anxiety, it can be helpful to separate the myths from the reality.
Myth #1
“Turbulence can tear apart planes”
Reality: Modern airplanes can withstand the worst turbulence.
Myth #2
“It’s safe to unfasten your seatbelt”
Reality: Unfastened passengers in a plane can be thrown around, so you should always fasten your seatbelt.
Myth #3
“Turbulence causes many plane crashes”
Reality: Pilots are trained how to fly during turbulence, and crashes caused by turbulence are very unlikely.
In conclusion, turbulence is mostly not dangerous. Most turbulence only lasts for a few minutes and doesn’t damage airplanes.
Ella Dunham, a Freelance Travel Journalist and Marketing Manager, boasts an impressive career spanning eight years in the travel and tourism sectors.
Honored as one of "30 Under 30" by TTG Media (the world’s very first weekly travel trade newspaper), a "Tour Operator Travel Guru" and "Legend Award" winner, Ella is also a Fellow of the Institute of Travel, a Member of the Association of Women Travel Executives, has completed over 250 travel modules, and hosts travel-focused segments on national radio shows where she provides insights on travel regulations and destinations.
Ella has visited over 40 countries (with 10 more planned this year).
