2.3 The Operating Environment and Aircraft Performance blog discussion

 An environmental factor that has caused accidents and near misses over the years is icing conditions. Icing conditions are prevalent on the ground and in the air, although the mitigation strategies to deal with the risk of icing on the ground vary from those utilized in the air. When ground icing conditions exist aircraft must get de-iced and anti-iced prior to departing. This has the ability to create massive delays and frustrations at airports which connects back to last week's discussion on ethics. In cases like this it could be easy for crews to want to skip deicing to save time and avoid a delay however in the interest of safety it must not be skipped. Ice has the ability to restrict the movement of critical control surfaces, or block probes such as airspeed indicators. In addition, ice adheres to critical surfaces such as the wings and horizontal stabilizer affects aircraft performance. On takeoff, ice with a “roughness similar to medium or coarse sandpaper, on the leading edge and upper surface of a wing, can reduce wing lift by as much as 30% and increase drag by 40%” (Transport Canada, 2010). This shows how severe the outcomes of not removing ice from the wings prior to takeoff can be, especially in situations with short runways or other performance limits. Ice removal is most often completed by the application of type 1 de-ice fluid and anti-ice is completed by the application of type 4 deice fluid. Anti-ice is a critical during periods of active precipitation as it prevents any ice from adhering to surfaces until the plane reaches 100 knots on the takeoff roll. A significant factor that impacts the effectiveness of anti-ice fluid is holdover time. In periods of heavy precipitation and / or extremely cold temperatures hold over times may be reduced to a point where there is not sufficient time for the aircraft to become airborne before the anti-ice fluid is not longer effective. In some scenarios, there may not even be a holdover time, which creates a situation in which no aircraft are able to depart. Overall, icing is a complex condition that requires understanding and cooperation among many parties to ensure safe aircraft operation.

References: 

Transport Canada. (2010, May 20). Chapter 1 - Air Law, the Clean Aircraft Concept. Transport Canada. Retrieved February 11, 2022, from https://tc.canada.ca/en/aviation/publications/when-doubtsmall-large-aircraft-aircraft-critical-surface-contamination-training-tp-10643/chapter-1-air-law-clean-aircraft-concept