If ground control observes a sudden cessation of visible vapor from a specific vent line, what might this suggest?

Answer

An unexpected change in insulation integrity or a pressure anomaly

A sudden cessation or dramatic increase in visible vapor from a specific area might signal an unexpected change in insulation integrity or a pressure anomaly in that line, prompting investigation.

If ground control observes a sudden cessation of visible vapor from a specific vent line, what might this suggest?
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