Originally Posted by
Eric Janson
The danger of freezing fog cannot be understated. Freezing fog contains super cooled water particles that will freeze instantly when disturbed by a rapidly moving surface.
I have had propeller blades collect 1/2cm of clear ice just on a short taxi in freezing fog.
The same is possible on the fan and compressor section of a jet engine.
The same can happen with supercooled water drops and dew laying on top the wing. Run your hand across it and it’s water, a minute later it’s turned to ice because you disturbed it. Any precipitation at or near freezing requires the utmost caution.