When heated water is used in the deicing process, when must the second step be performed?

The second step in the deicing process, which typically involves the application of a heated deicing fluid after the initial application, should be performed generally within 3 minutes. This time frame is critical because it ensures that any residual ice or snow does not reattach to the aircraft surfaces after the first application of deicing fluid.

Heated water is used as part of the deicing fluid to help remove ice, and if the second step is delayed beyond a certain window, the effectiveness of the deicing procedure can be compromised. This timeline helps in maintaining the aircraft's safety and performance by ensuring that the deicing process is effective before flight.

Timeliness in the deicing sequence is important due to the possibility of environmental conditions, such as falling snow or freezing rain, which can quickly form ice again after the initial treatment. Thus, performing the second step generally within 3 minutes maximizes the efficacy of the deicing process and helps maintain safe operating conditions for the aircraft.