Originally Posted by
Pace
Its not ideal but car stuff will cleanly remove it. Its up to you to dry the clean wing off before flight
Pace
I agree that "car stuff" is not ideal. It may contain methyl hydrate, which can have corrosive affects on aluminum. Drying the wing off afterward will not prevent corrosion risk if the methyl hydrate has seeped between lapped skins or into the structure. For aircraft in my care, the only liquid I would apply would be those approved for that purpose - on aircraft.
Me (having inspected aircraft before lesson): There's some frost on the wings
Instructor: Well spotted ... now let's go flying.
The regulations (Canadian, anyway) do not state that aircraft will not fly with contaminated wings, they state that a pilot is not permitted to attempt the flight. Some aspects of flying require good preplanning, frost prevention is certainly one of them.