Alexandra Pope, staff writer
June 12, 2011 — Air Canada pilot and blogger Capt. Doug Morris dropped by The Weather Network to explain how commercial aircraft pilots navigate severe weather.
Thunderstorms pose all kinds of hazards to aircraft, including sharp, unpredictable air currents, hail and, of course, lightning, Morris explained.
So, weather reports factor prominently in Morris' flight planning process.
“Today I’m off to Mexico City, and I noticed at home on the radar that there will be some thunderstorms building through the American midwest,” he said. “The tops of the thunderstorms are around 43,000 feet, and the highest altitude I’ll get today is about 38,000 feet, so I can’t go over top of them, can’t go through them -- I’ll have to go around them.”
In order to allow Morris to deviate around the storms, the flight dispatcher will add extra fuel, since deviations begin a full 100 miles away from the storm.
Lightning is actually one of the pilot's least concerns when flying around a storm, Morris said. However, strikes do happen, which is why airplanes are equipped with static wicks on the wings and tail.
“They discharge all the static buildup we accrue when flying near a thunderstorm,” Morris explained. “Usually all that static electricity dissipates from the airplane, but sometimes lightning does strike the airplane. It usually goes in one end and out the other end, and it might leave a small little hole, but when we land, maintenance will look it over and give us a clean bill of health, and away we go again.”
Lately, some pilots have had to deal with an entirely different airborne hazard: volcanic ash.
Ash from the recent volcanic eruptions in Chile has so far disrupted flights in South America, South Africa, Australia and New Zealand.
Travel delays are irritating for passengers, but they're necessary for their safety: ash not only creates poor visibility, but is also highly abrasive on jet engines, Morris said.
“It affects the engine performance and actually, it degrades the engine … to the point where the engine just may stop working.”