Wind Chill......Brrrrrrrrrrr!!
A day or two ago I was out fuelling with a student pilot I am training here at the Sudbury airport. I was bundled up in my winter flying suite, feeling toasty warm, until a sharp north wind sprang up from out of nowhere. “The weather man was right” I thought, “15 knots around noon”. Within minutes the temperature seemed to drop from -10 to @#$% freezing. Now, I can handle -10, but with the wind it was bitter! That made me think about how uncomfortable the wind chill makes us and how dangerous it can be during our Canadian winters. SO BEWARE!
After flight training, I decided to do a little research on “Wind Chill”. I found that the original wind chill formula was developed by two members of Admiral Byrd’s first Antarctic expedition in 1939. Their names were Paul Siple and Charles Passel. Paul and Charlie placed 250 grams of water in a plastic bottle, left it outside in the wind, and recorded the amount of time it took to freeze. This information was then developed into the first Wind Chill Index or WCI. It was later found that this WCI was not accurate, so in 2000 Canada took the lead on an International WCI conference. By 2001 scientists and medical experts from Canada and the US developed a new WCI from the International data collected. This new index is based on the loss of heat from the face, the part of the body that is most exposed to severe winter weather. If you want the entire story, Google “First wind chill index” and you will find a lot of information on the subject. I then found the Environment Canada Wind Chill Chart (see below) just to see what the temperature was, corrected for wind. At -10 with 15kt (27.75 KM/h) of wind the chart reads -20. So, without Mr. Siple and Mr. Passel on these windy winter days, we would still think it was just damn cold; but now we can actually see what damn cold looks like!
Safe Flying!
Glenn Graham
GACP President
