What causes airplane turbulence? As a traveller, you probably fall into one of two camps when it comes to airplane turbulence: scared stiff or happily blasé. You may not know that turbulence on an airplane is the most common cause of injury to air passengers. If the thought of turbulence fills you with dread, it's worth reading up on tips for fear of flying and how to sleep on a plane. Here we give you the lowdown on turbulence and whether you really need to obey the pilot's 'fasten your seatbelt' signs.
What is turbulence?
Turbulence is a sudden, violent shift in airflow, which leads to those familiar bumps and shakes on your flight. The level of turbulence is categorised as light, moderate, severe or extreme.
Light turbulence happens on almost every flight and many passengers won't even notice it. It feels like a bump on a road or chugging along a railway line, and causes just a metre or so of airplane movement up or down. With moderate turbulence, which is also common, the plane could deviate by three to six metres in altitude and you will have to put up with a few spillages of your inflight refreshments.
Severe turbulence is very rare, with a plane shifting up to 30 metres in altitude and people thrown around if they are not strapped into their seats. Most seasoned pilots only see a few minutes of severe turbulence in their careers; and if we're talking extreme turbulence, the majority of pilots and passengers never experience it.
What causes turbulence on a plane?
Different weather and environmental conditions produce different kinds of turbulence. Strong winds, updrafts, heat, severe thunderstorms, mountain ranges and those lovely puffy cumulus clouds can all give you a bumpy ride.
Clear air turbulence (CAT) is trickier to predict and is created when fast-moving and slower-moving air mix at the edge of a jet stream.
Wake turbulence is caused by the tight, circular tornadoes of air (wingtip vortices) trailing behind a plane, most pronounced during take-off or landing.
Interestingly, studies reveal that turbulence on airplanes is increasing with global warming. Rates of clear air turbulence caused by shifting jet streams rose between 40% and 90% over North America and Europe between 1958 and 2007, and this is expected to rise steeply in the coming years.
Is turbulence dangerous?
Although we sometimes hear scary stories of severe turbulence in the news, the US Federal Aviation Administration reports around 60 cases of injury caused by turbulence every year, with all the flights landed safely. It's the most common cause of injury in the air purely because injuries on flights are extremely rare in themselves. Your drive to the airport will have been more dangerous.
Most turbulence-related accidents are not life-threatening and occur at 30,000+ feet. Those injured are flight attendants and passengers out of their seats or not wearing seat belts.
In almost all cases, turbulence on a plane feels worse than it is, and results in a little discomfort and maybe a few spilt drinks, but nothing more. A plane cannot be turned upside down by turbulence.
Airplanes these days are built to withstand pretty serious turbulence and if a plane experiences severe turbulence it will be thoroughly checked after the flight to ensure everything is where it should be. Damage is rare.
How do pilots deal with turbulence?
Pilots understand turbulence and accept it as a normal part of flying, like traffic and potholes to drivers. Pilots are in constant communication with air traffic controllers, sharing information on spots of turbulence. As clear air turbulence can't be seen, predicted or detected by radar, this communication is vital. Air traffic controllers schedule flights to account for wake turbulence, but it can still happen occasionally.
When bad turbulence is detected pilots will adjust their altitude or route, more for comfort than for safety. They will always try to avoid the discomfort and increased anxiety that turbulence can cause for passengers. When it can't be avoided, they stick that helpful little 'fasten your seatbelt' sign on.
What you can do to reduce the effects of airplane turbulence?
It's very simple. Always obey the 'fasten your seatbelt' signs and get into the habit of wearing your seatbelt whenever you are seated. For a bit of added protection, avoid the back seats of the plane if you can as this is where you'll get the bumpiest ride. Sitting over the wings is thought to provide the smoothest flight. Now relax, you're in safe hands!