When a bumpy ride turns deadly: How worried should you be about turbulence? 

A Singapore Airlines flight from London to Singapore experienced such severe turbulence that a person was killed and several more were injured. The Boeing 777-300ER was diverted to Bangkok following the incident so that its aftermath could be assessed, including securing treatment for those requiring hospitalization. 

Should people be concerned the next time they board an airplane, particularly a long-haul intercontinental flight? 

Let’s look at what happened, so we can extract lessons learned. 

First, the airplane itself endured the turbulence. Commercial airplanes are built to withstand such shocks, so the likelihood that a plane’s fuselage would break apart midflight is extremely low. The Singapore Airline incident attests to its durability. 

Then there are the airplane occupants themselves. This is where safety procedures come into play, and why the flight attendants are there primarily for your safety, not just to provide in-flight amenities like food and beverage. Flight attendants have been trained to oversee every conceivable flight incident, including extreme turbulence. Their goal is to keep all passengers safe during such events and take any necessary actions to mitigate passenger risk. 

What many people may not realize is that, though a plane travelling at a constant velocity of 550 miles per hour may feel very calm — perhaps even calmer than when one drives at 60 miles per hour on a highway — what creates disruption in the airplane cabin is changes to its velocity, particularly rapid acceleration or deceleration. 

For example, when a flight gradually increases altitude, this creates a downward pressure on the occupants in the cabin, so passengers feel like they are being gently pushed down into their seat. The reverse effect occurs when a flight decreases altitude. 

Airplanes can fly because of the shape of the wings, which enables a difference in pressure between the air that travels above its wings (lower pressure) and below its wings (higher pressure). The resulting pressure difference produces lift, which enables a multi-ton airplane to get off the ground. 

Turbulence is caused by irregular air motion based on differences in air temperatures, pressures, and/or directions of flow. The net effect is that a flight feels bumpy when such air passes over and under the wings.  

To put this in perspective, turbulence acts much like speed bumps on a road. When we drive our automobile over speed bumps, we slow down so the disruption of going over the bumps minimizes any shock in our vehicle. The same phenomenon occurs with turbulence on an airplane. At 550 miles per hour, any air flow disruptions are magnified, creating what seems like random movement within the cabin. If the turbulence is sufficiently severe, passengers can be tossed around, risking injury to themselves and, possibly, other passengers.   

That is why when flight crews tell you to remain seated during a flight, and to keep your seat belt buckled; they understand the risks associated with turbulence. They also know that turbulence can occur at any time, and sometimes unexpectedly. This is particularly true with clear air turbulence. 

The nature of commercial air flights is that if just one person is not securely buckled into their seat during severe turbulence, this person can become a dangerous projectile, risking injury and even death to others on the flight. So buckling up is not just about your safety, it is about everyone’s safety. 

As we enter the busy summer travel period, with more flights in the air, the number of flights affected by air turbulence is certain to increase. Whether the severe turbulence experienced on the Singapore Airline flight will occur again remains to be seen. What this event has done is remind every passenger that turbulence is a real risk in flight, and keeping seat belts buckled throughout the flight may save your life and the lives of other passengers on your flight. 

What occurred with the Singapore Airline flights is a lesson learned and a story that should be told by every airline, to every passenger. Safety in the air requires everyone to be part of the safety solution. Buckling up is a critical part of that solution.   

Sheldon H. Jacobson, Ph.D., is a professor in computer science at the University of Illinois Urbana-Champaign.