Chapter 5 - Ground Crew Supplement

Deicing/Anti-icing Fluid on the Cockpit Windscreen

51.  The inherent properties of the fluids often results in the aircraft windshield wipers being rather inefficient at removing the fluids from the windscreen. In fact, the wipers will often merely smear the fluid resulting in a smudged windscreen, which makes it extremely difficult for the pilots to see out of the cockpit, especially during nighttime operations.

52.  Deicing Operators should be aware of this phenomenon and realize that even small amounts of deicing fluid covering flight deck windows can cause pilots to lose visual contact with the operation taking place around the aircraft. If this situation occurs, especially when hand signals are used as the only means to communicate, the communication between the pilot and the deicing operator may be impossible, and the overall safety of the operation may be compromised.

53.  In some instances it will not be possible to prevent deicing fluid build-up on the windscreens; however, the deicing operator should be aware of the negative implication of this situation. When an aircraft has been given depart clearance from the pad, the actual departure may need to be delayed while the pilot attempts to remove the fluid using windshield wipers, or while he waits for the fluid to run down the windscreen and thin out for better forward visibility. The very fact that deicing spray can reduce visibility from the cockpit down to nil, makes a compelling argument for the use of a hard wire or radio communication link between the PIC and the deicing crew.