Aircraft de-icing is the process by which the ice that forms on the fuselage is removed, as well as any type of contamination that may affect the aircraft’s performance.
The de-icing equipment consists of trucks that, by means of a telescopic arm, spray the aircraft with a mixture of water and anti-icing agent. These tankers are equipped with boilers that heat the mixture to 82ºC.
De-icing fluid mixture is composed of water and glycol: the water melts the existing snow and the glycol slows down the formation of ice on the aircraft.
In addition, a dye is added so that operators can check which areas have been decontaminated.
Typically, the surfaces that are de-iced are the vertical tail stabiliser, the horizontal stabiliser and the wings of the aircraft. These are the most important because they are where the control surfaces are located, so they need to be completely clear.
In addition, the landing gear doors, and also the radome (where the weather radar is located), are other parts to be de-iced.
However, it is true that, in extreme conditions, the aircraft must be de-iced in its entirety.
We have mentioned that commercial aircraft are equipped with powerful anti-icing systems, but how do our aircraft do it? How do we de-ice small aircraft?
To begin with, we have to bear in mind that most of our operations are carried out under VFR visual flight rules, so our flights are not performed under these conditions.
Even so, during the more advanced phases of training, when it is necessary to practice IFR instrument flights, the aircraft have several systems.
For example, the pitot tube, which registers the external pressure, is equipped with a heater, as is the propeller. In addition, the Diamond DA42s have a system in the wings to coat them with an anti-icing liquid or de-ice.
You have already learned the importance of aircraft de-icing systems to ensure safe operations. But, in addition to that, airports all over the world have their ‘Winter Plan’: specific actions to adapt operations to seasonal weather conditions.
These include the maintenance of runways with snow ploughs or the use of melting liquids to prevent passengers from falling in transit areas.
In addition, during winter operations, the runway coefficient of friction is measured more frequently, as it is a fundamental data for pilots to calculate the necessary take-off and landing distances.
