Comments for Flying in turbulence… at http://www.askcaptainlim.com , comment 1 to 1 out of 1 comments http://www.askcaptainlim.com Wed, 08 Sep 2010 06:02:55 +0100 FeedCreator 1.7.3 http://www.askcaptainlim.com/index.php?option=com_content&view=article&id=915:flying-in-turbulence&catid=39:air-turbulence&Itemid=58#comment-931 Dear Captain Lim, Thank you so much for the comprehensive and reassuring reply. I appreciate your providing this great public service despite what is clearly a demanding schedule. Your response helps clarify a lot of things and for that I am grateful. Based on my limited knowledge of physics and the atmosphere, and building on what you have said, I'd like to offer a few further thoughts that might be of encouragement and clear up some misconceptions for fellow air travelers. See if you agree with these. • Air in the atmosphere (even in the major storms that pilots can detect and avoid) typically does not move very fast, vertically, compared to a modern jet airplane at cruise. In fact, if you were just standing still in a "turbulent" area the updraft or downdraft is typically a few meters per second -- like riding an elevator in a tall skyscraper. • Even horizontal shears, though more pronounced at times, are minor compared to cruising speeds. A hurricane force wind or tornado could hit 200+ mph, but even in that extreme and avoidable case, compare that to a jet going 500+ mph. • The reason turbulence seems to buffet the plane is because you are moving fast horizontally, so you are rapidly entering and exiting these areas of changing wind. The relative speed differentials encountered are small compared to the airspeed of the plane. • At cruise you are not feeling any acceleration, even though you're moving fast. This is Newton's second law. So even if the plane is bumped around, these are really minor deviations from a fairly straight trajectory. You feel differently in your seat because all you feel is acceleration, not velocity, and there is no nearby lane marking or other object to give you some reference. • I went back and looked, and confirmed that no modern large jet airliner has ever crashed due to turbulence, as I think you have stated before. Inattention to procedures by maintenance crews, airlines, or occasionally by crew seem to be greater safety risks, but even then rarely produce fatal accidents. • Modern airplanes and control systems are amazingly resilient in recovering from difficult situations. Engine failures, holes in the fuselage, stalls and dives -- all can be recoverable situations nowadays given good maintenance and attention to procedures and training. • In contrast to our daily lives, getting on a plane involves relying on someone whom you are not qualified to replace. You also don't get much information or have much context when sitting in the cabin, and you don't have the alternative of just getting off. This is the real anxiety producer. Arming yourself with knowledge is key. Your website, Capt Lim, is a huge help in giving people information about flying. Thanks again for your great public service, happy new year, and many safe travels to you also. RM - RM Wed, 06 Jan 2010 04:27:09 +0100