Type IV fluids provide the longest holdover time for protection amongst all fluids. Which statement is true?

Type IV fluids provide the longest holdover time for protection amongst all fluids. Which statement is true?

• A. Shortest holdover time
• B. Longest holdover time
• C. Moderate holdover time
• D. No holdover

Answer: (B)

Holdover time is the estimated period a de-icing/anti-icing fluid remains effective before ice can form on aircraft surfaces. Type IV fluids are thicker and more viscous, forming a durable film that stays on the surfaces longer and resists ice buildup during precipitation. This longer-lasting protective layer means holdover times are typically longer with Type IV than with the other common fluids, which are thinner or designed for shorter holdover. Real holdover times depend on temperature, precipitation type and intensity, wind, and surface conditions, and must be taken from holdover time references. So, the true statement is that the holdover time is longest for Type IV fluids.

Holdover time is the estimated period a de-icing/anti-icing fluid remains effective before ice can form on aircraft surfaces. Type IV fluids are thicker and more viscous, forming a durable film that stays on the surfaces longer and resists ice buildup during precipitation. This longer-lasting protective layer means holdover times are typically longer with Type IV than with the other common fluids, which are thinner or designed for shorter holdover. Real holdover times depend on temperature, precipitation type and intensity, wind, and surface conditions, and must be taken from holdover time references. So, the true statement is that the holdover time is longest for Type IV fluids.