As reported by the Toronto Globe and Mail,on
January 11, 2008, an Air Canada, Airbus A319 from Victoria, British
Columbia to Toronto, Ontario had to make an unscheduled stop in
Calgary, Alberta, the previous day, due to a few moments where it
encountered a pocket of undetectable turbulence in flight. Ten people
were taken to the hospital, but none with life threatening injuries.
Here is a Canadian video report. This incident is what is known as "Clear Air Turbulence".
NASA’s Dryden Flight Research Center, at Edwards Air Force Base in California has been one of the leading research institutions looking into these phenomena along with NASA's Langley Research Center in Virginia. They describe it this way:
“Atmospheric turbulence is the leading cause of in-flight injuries experienced by the flying public, and can result in death in extreme situations.
Turbulence is often associated with visible storm systems. In these situations, the turbulent conditions can be observed by radar and the aircraft can avoid the dangerous region. Not so with clear-air turbulence, a condition occurring at cruise altitudes that has few if any visible warning signs for even the most conscientious pilots.
Clear air turbulence is often found on the outskirts of thunderstorms, up to 50 miles away from the actual storm activity. It also occurs near the boundaries of high altitude air currents called jet streams and in the vicinity of mountain ranges and surface weather fronts. There are currently no effective systems to warn flight crews that they are approaching clear air turbulence. One of the only ways that commercial or other aircraft can avoid encounters is to heed recent pilot reports of turbulence and if possible, avoid the hazardous region of the atmosphere.
Additional work in the turbulence research program is under way to improve understanding of the clear air turbulence phenomena and thereby improve the quality of turbulence forecasting.”
For almost ten years, NASA has been working to devise a system by which aircraft can detect these atmospheric gremlins before they send passengers tumbling around the cabin like the recent Air Canada incident. Working with various test beds that have included a 1960’s era Lockheed Electra prop-jet, a DC-8 jetliner and a Boeing 757 jetliner, NASA researchers and others from the National Center for Atmospheric Research in Boulder, Colorado have looked at a couple of different methods involving hardware, software and laser pulses to detect the rough air pockets. (Animation of how the laser system works)
Size of the hardware and cost of the system are still factors that might hinder airlines from adopting it. It would not be the first time the airlines passed on a NASA developed device that could increase air safety. NASA Dryden helped to devise a system that could fly a plane by engine thrust only in the mid-1990s using an MD-11 aircraft as a test bed. This would allow a plane that loses use of the wings, rudder or flaps, such as the famous United Flight 232 in 1989, the ability to land safely. While not great in size the airlines claimed the cost of installation was too great for their large fleets and the likelihood of another such incident was minimal. What is the cost of safety though? Air travel is incredibly safe, but why not make it safer?
Until the airlines decide whether to buy into being able to avoid the turbulence gremlins, I suggest you keep your seat belt fasten. Bashing your head into the light and air vent panel above you could lead to serious injury. Look for hand holds below the overhead bins to hang onto, if you have to walk about the cabin. If you are walking about the cabin, more than likely, you are on the way to the lavatory. There is usually one handle in the lavatory near the door. However, in there, a big bump could cause a nasty case of blue butt, even if you hang on. If you have ever looked into one of those toilet bowls, you will know what I mean.
For more information on NASA’s research in the area of Clear Air Turbulence, go to: