Light snow falls as Air Ontario flight 1363 stops in the remote northern community on its way from Thunder Bay to Winnipeg. Temperature hover around freezing. Visibility is decreasing, if the flight does not leave soon, it could be grounded indefinitely. Finally, an hour behind schedule the plane taxis to runway 29. Captain M performs a brief engine run up. Heating the engines to rid them of any accumulated snow and ice. Then he begins his roll down the runway.
The F28 reaches its takeoff speed – 80 knots. Clearly, that is something wrong.
The F28 struggles to get airborne.
Within 24 hours, a team of investigators from the Canadian Aviation Safety Board arrives at the scene. To solve the mystery they (call) through survivor and eyewitness statements. A common thread emerges.
“They said in a witness statement there was snow and ice on the wings when the airplane attempted to takeoff”
Mr. R studies weather charts for clues. The charts show that during the half-hour the F28 was on the ground, visibility shrank from four kilometers to less than one kilometer because of the snowstorm.
Investigators consult the F 28`s manuals to study its anti-icing systems. They find that only the wings leading edges are protected.
“The aircraft had heated leading edges of the wings, and the heat was provided by bleed air from the compressors on the engines.”
The anti-icing system was working, but since it only heats the leading edge, it likely didn’t clear ice that formed on the surface of flight 1363`s wings.
Investigators suspect that snow and ice buildup, what experts call wing contamination, may have played a major role in the crash.
Fokker engineers have run simulations of the crash.
“They were able to get some very good data. In terms of the performance of the airplane simulating the type of load, temperatures, etcetera that the Dryden aircraft would have been exposed to.”
Investigators make a crucial discovery about the design of the F 28. Because of the angle of the wings, a very small amount of ice makes the planes susceptible to stalling. The simulations support what witnesses saw. Investigators are now certain that contaminated wings caused the crash.
- In what weather conditions did Flight 1363 stop for refueling?
Flight 1363 stopped for refueling in poor weather. The weather was poor due to temperature hovered about freezing and considerably decreased visibility.
- Why was the flight crew eager to depart as soon as possible? What other reasons for delays do you know? Are there any ways of preventing delays?
The flight crew was eager to depart as soon as possible because the fight could be delayed indefinitely due to weather.
Let’s talk about the typical reasons that cause flights to depart or arrive late.
The first reason is weather. This is probably the most obvious and most common cause for delayed flights. There are three areas where weather affects flight schedules: at the origin airport, in-flight and at the destination airport.
The second reason is traffic. Many factors can cause air traffic, and all impact flight arrival and departure times.
The third reason is go-Arounds. A go-around occurs when an aircraft is just about to land at an airport and the pilot decides it is not safe to land. So you will see (or feel) the plane suddenly increasing altitude, as if it was taking off again. Of course this affects the arrival time for that flight, as it could take up to 30 minutes for the aircraft to return and land again.
The fourth reason is technical problems. The bane of travelers and airlines alike, mechanical problems affect arrival schedules too.
Another reason is terroristic acts. Nowadays this threat can delay flights for a long time.
Passenger baggage identification may affect schedule as well.
- How long was the delay? What procedure did the Captain perform before commencing take-off?
The delay took a one hour. The Captain ran up engines to clear them of snow and ice before commencing takeoff.
- In what way was the takeoff abnormal?
Takeoff was abnormal due to problems with climbing. Aircraft was unable to climb.
- What did the investigators analyze first of all?
Investigators analyzed eyewitness’s statements at first.
- According to the investigators, what was the first possible reason for the crash?
Snow and ice accretion on wing surface were the first possible reason for the crash. It’s called wing contamination.
- What information did the investigators get from the weather charts?
The investigators got information about rapidly decreased visibility from 4 to 1 km due to snowstorm.
- Was there a malfunction of the anti-icing system? Why were the wing surfaces NOT cleared from snow and ice?
No, there wasn’t. The anti-icing system worked properly but only the leading edges were protected. I suppose that no deicing procedure was made.
- What allowed the investigators to receive a clear picture of the flight? What exactly was simulated?
Flight simulation of that accident was allowed the investigators to receive a clear picture of the flight. Type of load, temperature, weather conditions and takeoff procedure were simulated.
- How did the aircraft design contribute to the crash?
Because of the angle of the wings, a very small amount of ice makes the planes susceptible to stalling.
- What was officially declared as the main reason for the crash?
Wing contamination was officially declared as the main reason for the crash.
- What adverse weather conditions that can affect flight safety do you know? What problems can they lead to? What makes weather such a significant factor in aviation?
There are many adverse weather conditions that can affect flight safety such as cyclonic activity, thunderstorm, line squall, thick fog, wind share, blowing snow, heavy shower rain, dust or sand storm, lightning, icing, and severe turbulence. These problems can lead to malfunctions, failures, problems with aircraft controllability. All the flights are performed in Earth’s atmosphere. Atmosphere is that place where weather is developing.