During the anti-ice phase of a two-step process, how can holding time be increased?

Raising the glycol content to 100 percent is an effective way to increase the holding time during the anti-ice phase of the de-icing process. Glycol-based fluids are designed to provide a barrier that prevents ice and snow from adhering to the aircraft surfaces. The higher concentration of glycol enhances the fluid's anti-icing properties, allowing it to maintain a protective layer for a longer duration. This essentially prolongs the time before any ice formation can begin, which is critical for ensuring the aircraft remains safe and operational during cold weather conditions.

Increasing glycol content also helps in lowering the freezing point of the fluid, allowing it to function more effectively in colder environments where conventional fluids might lose their efficacy. In environments where ice and frost can rapidly accumulate, having a higher glycol concentration can make a significant difference in maintaining aircraft performance and safety.

In contrast, while heated air may assist in the application process, it doesn't directly affect the holding time once the fluid is applied. Similarly, fluid volume can play a role in coverage but does not inherently extend the holding time as effectively as adjusting glycol concentration. Lowering ambient temperatures would likely decrease the holding time rather than increase it.