It's good to see some some sensible stuff on here at last!
The ONLY fluids that should be used for de-icing are the approved Type I to IV fluids. They should be applied in the manner that the manufacturer recommends.
Never ever use anything else. Especially not plain bl**dy water!
Now back to the original question.
Hello, it's been a while since I took my Met exam and I'm trying to refresh my understanding of frost and it's effect on flying VFR. On days like this weekend, where there's frost forecast to say 11am, what's the implication of (air and ground) frost for flying a plane hangared overnight? Maybe I'd like to get the plane out around 9am, do my checks, fuel up and then depart an hour later. If I plan to avoid flying in cloud what should I be aware of regarding frost during preflight checks and departure? Thanks for your help.
Why not get the aircraft fuelled the night before, do your preflight checks in the hangar, then just pull it out and go if you are worried about the aircraft icing up whilst parked outside.
Don't mess around with icing. If it's below freezing on the ground, then do everything you can to avoid getting any moisture on the aircraft.
If the relative humidity is high and the temperature is low, then think about using a deicing fluid that has a decent hold over time to protect you from frost and once airborne, keep a close eye on the areas of the aircraft that ice up first (places like the temp guage probe on a PA28 for example) to give you some pre-warning of icing issues and keep out of cloud and rain.