Chapter 4 - Preventative Measures and Deicing Procedures

Techniques for Implementing the Clean Aircraft Concept

  • Establish training programs to update crewmembers on the hazards of winter operations, adverse effects of ice formations on aircraft performance and deicing and pre-take-off procedures during ground icing operations.
  • Establish training programs for maintenance or other personnel who perform aircraft deicing to ensure thorough knowledge of the adverse effects of ice formations on aircraft performance and flight characteristics, critical components, specific ground deicing and anti-icing procedures for each aircraft type, and the use of ground deicing and anti-icing equipment including detection of abnormal operational conditions.
  • Procedures are utilized, that all critical areas are inspected, and that all critical components of the aircraft are clean prior to departure.
  • Perform thorough planning of ground deicing activities to ensure that proper supplies and equipment are available for forecast weather conditions and that responsibilities are specifically assigned and understood. This is to include service contracts.
  • Monitor weather conditions very closely to ensure that planning information remains valid during the ground deicing or anti-icing process and subsequent aircraft operations. Type or concentration of FPD fluids, deicing or anti-icing procedures, and departure plans should be altered accordingly.
  • When applicable, use two stage deicing process where ice deposits are first removed, and secondly all critical components of the aircraft are coated with an appropriate mixture of FPD fluid to prolong the effectiveness of the anti-icing.
  • Ensure thorough co-ordination of the ground deicing and anti-icing process so that the final treatments are provided just prior to take-off.
  • At non-centralized locations, provide and use remote sites near the take-off position for deicing, anti-icing and final inspection, to reduce the time between deicing and take-off.
  • Use multiple aircraft deicing or anti-icing units for faster and more uniform treatment during precipitation.
  • Be knowledgeable of the variables that can reduce holdover time and the general effects of those variables.
  • Be aware that the HOT Guidelines are not exact values and that as the ground icing conditions and circumstances change, the applicable HOT values will change. Continued vigilance is required at all times during ground icing conditions.
  • Ensure communication with the deicing/anti-icing crew is maintained at all times. It is essential that the PIC know exactly what surfaces are being treated and when deicing/anti-icing operations are complete and crews are clear.
  • Do not start engines or engage rotor blades until it has been determined that all ice deposits have been removed and that all ground personnel and equipment are clear. Ice particles shed from rotating components may damage the aircraft or injure ground personnel.
  • Be aware that certain operations, such as power back, may produce recirculation of ice crystals, snow, or moisture.
  • Be aware that operations in close proximity to other aircraft can cause snow, ice particles or moisture to be blown onto critical aircraft components, or can cause dry snow to melt and refreeze.
  • When aircraft are operating on slush or wet surfaces, ground crew should be particularly alert for contamination of the wheel wells, the underside of the belly and the control surfaces. Do not take-off if snow or slush is observed splashing onto critical areas of the aircraft, such as wing leading edges, during taxi.
  • Be aware that SAE Type II and Type IV fluids should be used on aircraft with rotation speeds (Vr) above 100 knots.
  • Use FPD fluids that are approved for use by the aircraft manufacturer. Some fluids may not be compatible with aircraft materials and finishes, and some may have characteristics that impair aircraft performance and flight characteristics or cause control surface instabilities.
  • Do not use substances that are approved for use on pneumatic boots (to improve deicing performance) for other purposes unless the aircraft manufacturer approves such uses.
  • Use FPD fluid types and concentrations that will delay ice formations for as long as possible under the prevailing conditions.
  • Establish quality assurance programs to ensure that FPD fluids being purchased and used are of the proper characteristics, that proper ground deicing and anti-icing.
  • Do not attempt a take-off, under any circumstances, if there is, for any reason, doubt as to the condition of the critical surfaces.

When in doubt... ask, investigate, check!