Chapter 4 - Preventative Measures and Deicing Procedures

Central and Remote Deicing

53.  Some facilities employ remote deicing that is conducted near the end of the active runway. This practice has diminished in the last few years in favour of central facilities that can capture and recycle spent fluid, for environmental reasons.

54.  Certain large airports have created highly automated and efficient Central Deicing Facilities (CDF) that can accommodate many aircraft at one time. They employ the latest technology to expedite and control the flow of aircraft from the gate area to the deice pads which in turn minimizes takeoff delay time after the de/anti-ice procedure.

55.  State of the art deice vehicles along with highly trained crews ensure that deicing operations are conducted efficiently and safely. The facilities have underground storage tanks that house fluid reserves and capture the runoff fluid from the aircraft for recycling purposes. They have the ability to adjust the amount of FPD in deicing fluid, called "Proportional Mixing" or "Variable Blend", for the given conditions. This process utilizes the automation of these facilities to adjust the fluid concentrations for the given weather conditions, which in turn become a cost savings for the operators. One operator has developed a program where all "Remain Over Night" (RON) aircraft are deiced with forced air, when dry snow conditions exist, during quiet hours. This minimizes the amount of deicing operations the next day as well as reducing the amount of deicing fluid utilized.

56.  Voice and data transmission are conducted via set procedures and controlled by centralized operations centers. Controllers here can view each aircraft in the deice bay and its current stage of deicing, as well as maintain contact with each aircraft and the individual deice vehicles. Computer displays installed in the control centers and the deicing vehicles display updated information on aircraft status throughout the entire deicing process. Electronic message boards advise Air Crews of their status in the deice pads such as, the type of fluid being utilized, posting the time when final application of fluid commenced, the completion of spraying operations, and radio frequencies to contact ATS when deicing operations has ceased and all deicing crews are clear.