Most people who have flown on a Northern Canadian flight have had experience flying during cold weather. The Northern airlines has years of experience operating in all weather conditions, especially the one season that Canada is famous, in some cases, infamous for – winter. Here are a few common questions:
1. Is it more difficult to fly when it’s cold?
Yes, because similar to automobiles, operating machinery in bitter cold requires more preparation like preheating engines, block-heaters, window scraping or aircraft de-icing.
No, because an airplane performs better at cold temperatures. Using some complicated thermodynamic calculations I can show that as air temperature drops, the density of the air increases, but I’ll spare you. This ‘denser’ air means that the engines develop more power than they develop on a warm day – the aircraft has more ‘get up and go’ on a cold day. Combined with the increase in engine power we get an increase in lift. The cold air flowing over and under the wings allows the wings to make more ‘lifting force’.
2. Runways must be slippery and more difficult to take off from and land on in cold weather?
Runways are just like roads in some respects to winter conditions but runways differ in the treatment they receive and in the way we, as pilots, prepare for possible poor conditions. Runways get a lot more care and attention from snow plows, sweepers and graders. Analysis of a runway’s friction is also provided to our pilots. This is performed by a vehicle mounted decelerometer which measures how quickly a vehicle stops when brakes are applied. This measurement is expressed as a coefficient of friction called the CRFI (Canadian Runway Friction Index). Pilots and dispatchers will take this CRFI value and chart wind speed, wind direction and aircraft weight to determine if the runway conditions are safe – if not, we simply do not land or take off and the airports maintenance crews continue working on the runway.
3. De-icing or spraying the wings, an inconvenience?
No, because it’s a fact of life and a necessity when operating in Canadian winters. Ice and snow that sticks to an aircraft’s wings cause the high speed air that flows over and under the wing to become rough or turbulent. Imagine a creek flowing over a rocky creek bottom, resulting in ripples and rapids. This turbulent air reduces the wing’s lift and increases the drag on the wing. We remove any snow or ice that is sticking using brooms, blowers or de-icing fluid. De-icing fluid is a heated ethylene or propylene glycol based fluid which is sprayed over the entire aircraft to wash off and melt off any ice or snow on the aircraft. The de-icing fluid is either orange or green in color and due to the high glycol content has a very low freeze point.
As you look out your window, while sitting in a warm aircraft, gazing at the spectacular winter landscape of the Canadian north passing underneath, know that all employees at airlines that fly in the Canadian North are more than comfortable and specially trained to deal with the hardships and benefits of our winter.
Canadian Airline Blog
By Laval St. Germain, Chief Pilot Canadian North Airline
Thu, Dec 23 2010 10:59 AM
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