A PBS NewsHour transcript in 1997 contains very good information about CAT, Clear Air Turbulence, or much more simply, “air pockets”. Here are some excerpts:
Since 1981, two people have died in air turbulence incidents, one aboard United Airlines Flight 826, where a 32-year-old Japanese woman suffered a fatal head injury when her body was hurled against the ceiling of the plane.
Early analysis of the aircraft’s flight data recorder showed that the 747 initially rose suddenly, then plunged six seconds later about one hundred feet.
According to ABC News Aviation Specialist John Nance, when dealing with clear air turbulence pilots have almost nothing, except their own analysis and experience of the weather reports, where the tropopause is — the layer between the troposphere and the stratosphere, the temperature changes that they may run into, and indications of high clouds that might tell them that they’re running into or out of a jet stream.
Also according to Nance, severe turbulence or clear air turbulence is an extreme rarity. Moderate turbulence is about as bad as it gets. What pilots try to do is avoid any areas of severe or clear air turbulence. Sometimes they can’t. The only tool they have available is to either change altitude, which is what they normally do (Pilots ask other flights, and/or ask the controller — Is it smoother at 33? Is it smoother at 31? ), or vary the speed, but at high altitude, you don’t have the option of slowing down a lot. So that really leaves them with only the option of changing altitude, or changing course.
So what do you think? Do you think you’re going to buckle up your seat belts next time?
Related Links: http://www.turbulenceforecast.com/
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