I just got off a flight that experienced severe turbulence mid air and was really afraid. At some point I felt the plane would crash...Lol. You won't blame me. Who wouldn't be afraid when you are suspended at 33,000ft above sea level. I decided to do a little study on airplane turbulence and these are my findings.

WHAT IS AIR TURBULENCE?

Turbulence at higher altitudes is more likely caused by weather conditions creating pressure differentials which again disrupt the air flow. It often causes a quick drop in altitude which you feel by being lifted from your seat, or even a climb which presses you into your seat. When you are seated inside the aircraft cabin these movements feel amplified and you may feel like the aircraft has moved much more than it actually has. There are four categories of air turbulence.

a. Light turbulence:This type of turbulence is so common it happens on nearly every flight, says veteran pilot and Seneca College aviation instructor Robert Johnson. It's the kind that causes "slight, erratic changes" to the plane's altitude or tilt, according to Transport Canada. Unless you're a nervous flyer, you'll probably be unfazed by this type of turbulence. At its lowest levels, you might not even notice it.

b. Moderate turbulence: If you're a frequent traveller, you may have been unlucky enough to experience moderate turbulence, where the plane's altitude could change by up to six metres. Your drink will probably spill, and you'll feel a definite strain against your seatbelt.

c. Severe turbulence: "With severe turbulence, you definitely get tossed about and can have injuries," says Johnson. He adds that the pilot could momentarily lose control of the plane, regaining it quickly. The plane's altitude could change by up to 30 metres.

Extreme turbulence: During this extremely rare type of turbulence, "pilot control is definitely lost and there is a very significant risk of aircraft damage," says Johnson.



WHAT IS THE CAUSE OF AIR TURBULENCE

The most common type of turbulence is called "clear-air turbulence," says Johnson. It occurs when cold and warm air come together. It's most common at altitudes of 7,000 to 12,000 metres. Clear-air turbulence feels more severe to passengers than it does to the crew on the flight deck, which can make for a stressful flight. However, all forms of air turbulence can be caused by a number of factors, including heat, jet streams and flying over mountain ranges. Severe turbulence is often attributed to a combination of these elements that make the air even more unstable. A severe thunderstorm can also cause violent turbulence; pilots tend to avoid flying in thunderstorms for that very reason.


CAN AIR TURBULENCE CRASH A PLANE?

In one often cited accident 50 years ago, the tail fin of a British Overseas Airways plane was torn apart by severe turbulence, causing the aircraft to crash.

However, planes today are designed to be much stronger. Modern commercial aircraft were created to withstand forces one-and-a-half times stronger than anything that's been encountered in the last 40 years of flight.

Substantial damage to a plane by extreme turbulence is still possible, but it's extremely rare and a crash is even more unlikely. In 1993, severe turbulence tore an engine from a cargo plane over Alaska, but the plane was still able to land safely.

Thanks for the information!