Contents
What are holdover tables?
Tables of Holdover Times for different fluids and prevailing conditions are published regularly and provide indication as to the time frame of protection that could reasonably be expected in each situation. These Tables contain elapsed time ranges which represent indicative maximum holdover times.
What is a holdover time?
Holdover time is the estimated period for which anti-icing or deicing fluid will prevent the accumulation of ice, snow or frost on the aircraft. Type I is a thin deicing fluid used to quickly remove ice and snow from aircraft surfaces.
What is the minimum glycol content of a Type 2 de icing anti-icing fluid?
50%
Type II fluids contain at least 50% of glycol and a corrosion inhibition package. Furthermore they contain pseudoplastic thickener system which additionally protects the aircraft against Re-freezing (Anti-Icing) due to its film-forming properties.
What is Two Step de icing anti-icing?
Two-Step De/Anti-Icing The first de-icing step removes the frozen contaminants, usually using Type I fluid. The second anti-icing step can use Type I, II, III or IV fluids. The HOT clock starts at the beginning of the second step, gaining quite a few minutes in HOT compared to a one-step process.
What information is included in the deicing code?
The Code communicates the following information to the aircraft commander by referring to the last step of the fluid treatment procedure in the following sequence: the fluid type – Type 1 Fluid, Type 2 Fluid, Type 3 Fluid or Type 4 Fluid.
Which is the most effective anti-icing fluid?
SAE Type II, III, or IV fluids are normally used for anti-icing because they are thickened to provide longer holdover times than Type I fluids. They are most effective when applied unheated and undiluted to a clean airplane surface.
How do you use anti-icing?
The fluid must be heated to 60 – 80C (140 – 180F) at the nozzle and applied in sufficient quantities to provide for adequate heat transfer to aircraft surfaces during the second, anti-icing step. The one-step method uses heated, diluted fluids to de-ice and anti-ice in one step.
What are the guidelines for estimated Holdover Time?
Holdover Time Guidelines: Series of tables that provide estimated holdover times (in hh:mm). Fluids are divided by fluid type (Type I, II, III, and IV), aircraft construction materials (Type I only), fluid brand (Type II, III, IV), aircraft rotation speed (Type III only)]
What are the holdover times for active Frost?
Holdover Time (HOT) Guidelines for Winter 2020-20217 Table 1: Active Frost Holdover Times for SAE Type I, Type II, Type III, and Type IV Fluids8 Table 2: Holdover Times for SAE Type I Fluid on Critical Aircraft Surfaces Composed Predominantly of Aluminum9
How is the Holdover Time for anti icing determined?
The more moisture present, the shorter the holdover time. Both the type of precipitation and its intensity are key factors in determining HOT. Type I must always be applied heated and diluted. It is essentially a de-icing fluid that can also be used for anti-icing in a two-step process.
What are the holdover times for Newave ICE Clear II?
Table 12: Type II Holdover Times for Kilfrost ABC-K Plus19 Table 13: Type II Holdover Times for Kilfrost Ice Clear II20 Table 14: Type II Holdover Times for Newave Aerochemical FCY-221 Table 15: Type II Holdover Times for Newave Aerochemical FCY-2 Bio+22 Table 16: Type II Holdover Times for ROMCHIM ADD-PROTECT Type II23