‘We generally don’t get more than a general warning.’
– Capt Chesley Sullenberger, American retired commercial pilot.
Time was, I was a very anxious flier. Not a take-the-bus-across-the-continent-rather-than-fly type, but certainly one who pretty much dreaded getting on an airplane.
It was an acquired anxiety, an apprehension that took up lodging in my gut during a day bouncing around in a small plane in stormy weather during the Jane Austen Society of North America (JASNA) book tour in 2015.
I had eyed the skies before takeoff and thought to myself, “Does the pilot intend to fly in this?”
Indeed he did, perhaps to test his ability to dart and dodge between the thunderheads. The experience left me envying the comparatively placid workday of a ping-pong ball.
That was the day my wife and I flew to Ireland. Our destination was Dublin, but the weather was so bad that our flight was diverted to Limerick. I tried to tell myself the bouncing and juddering were nothing to worry about — until, that is, one of the strapped-in flight crews screamed.
Two recent news reports brought those experiences back. Last week, a Singapore Airlines flight hit extreme and unexpected turbulence near the end of a flight from London to Singapore. A male passenger died, apparently of a heart attack, and more than 40 others were injured, some very seriously.
On Sunday, a Qatar Airways flight bound for Ireland hit strong turbulence, causing injuries to six passengers and six members of the crew, eight of whom required hospital treatment.
What most fliers fear most, of course, isn’t in-flight injury but rather that turbulence will cause an airplane to crash. That was my worry — until I was deployed as a metrics specialist at Boeing headquarters in Virginia, U.S. There, I learned this comforting piece of information: Turbulence has rarely knocked a commercial airliner out of the sky.
One has to go back a long way to find the last confirmed instances of commercial airline disasters caused by high-altitude turbulence alone. (Microbursts during takeoffs or landings are a slightly different story.)
Here’s what I found: On Dec 2, 1968, a Wien Consolidated Airlines prop-jet suffered structural failure and crashed at Pedro Bay in Alaska after encountering severe to extreme turbulence, an accident that killed all 36 passengers and the three-person crew.
On March 5, 1966, a British Overseas Airways Corporation flight with 113 passengers and an 11-member crew encountered severe clear-air turbulence near Japan’s Mount Fuji. The extreme conditions caused the plane’s vertical fin to break off. The fin then struck one of the horizontal stabilisers, which also broke away. The resulting side pressure ripped the engines off.
But those calamities were more than half a century ago.
It might sound weird, but today’s planes are built to be a little flexible. You can expect the wingtips to wiggle a bit during turbulence, and the plane flexes along the length of its tube a little too. So the likelihood that a plane’s fuselage would break apart midflight is extremely low.
The bigger the plane, the smaller the effect of any turbulence compared with a smaller plane in the same situation. But you might have noticed that the Singapore Airlines Flight 321 plane was a large Boeing 777 — one of the biggest planes currently flying.
So yes, while you’ll feel a greater effect from the same amount of turbulence on a small narrow body 737 compared with a big wide body 777, severe turbulence will still feel severe no matter what plane you’re on.
What many people may not realise is that a plane travelling at a constant velocity of 885 kilometres per hour can feel very smooth and calm. Perhaps, it might even feel calmer than driving at 100 kilometres per hour on a highway. However, what can disrupt that calm are sudden changes in its velocity, especially 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 seats. 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.
Think of it like driving over speed bumps on a road. When you drive over speed bumps, you slow down to make the ride smoother and avoid any big jolts to your car. Turbulence on an airplane works similarly. When it flies at about 885 km per hour, any small changes in the air can feel like bumps, creating what seems like random movement within the plane.
That doesn’t mean turbulence can’t cause death if people are thrown around inside a plane. It can.
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 (CAT).
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 a busy 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 Airlines 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 happened with the flight are 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.
The views expressed here are those of the columnist and do not necessarily represent the views of New Sarawak Tribune.
