Bri85

you got it freezing level charts.


i use
http://adds.aviationweather.noaa.gov/



-I was told even equip for icing conditions 18nm is the limit when flying into icing conditions

SongMan

Thanks you!

So we climb in icing condition incasee of temp inversion? or is it to climb to an altitude that will give below -20 Degrees to stop icing from further developing?

Also, is supercooled water droplets the only cause for icing? Can a mist or fog be supercooled and cause icing?

patton33

well the cause for icing is generally temperatures at or below freezing (sometimes +2 but that's a different debate) and visible or present moisture. Don't have to be in the clouds to pick up ice, frost can and will form at night. In regards to the super cooled water, water can be super cooled from 0 all the way to -40 C, after that it becomes a suspended ice particle.

As for the climbing in icing conditions, generally speaking attempting to out climb the ice is a bad plan for light GA aircraft as it generally cannot be done. Depending on the severity of the ice, the performance of the aircraft and the altitude you are at, you'll never be able to climb above it. It can sometimes be done/be a good idea, especially if its a thin cloud layer or as you said there is a strong temperature inversion but generally speaking, no.

An additional factor to look at when it comes to ice, is what type of precip is occurring and what is the temperature. There are three types of ice, clear, rime and mix and they each form with different types of precip and temperatures.

When it comes to icing and GA aircraft the rule of thumb i use is that if it is +3 or colder at the MEA, its a no go. If there are pireps or airmets up for ice, also a no go.

SongMan

+3 or colder in MEA? You mean with visible moisture, right? or regardless of visible moisture, you don't go with temp being +3 or colder?

thanks

patton33

i factor in visible moisture, cloud bases, cloud types.

Its especially important in the mountainous environment where I instruct because the MEA (or sometimes even the MOCA) is at 10k feet which generally means there really is no climbing and there is no going down unless its for an approach or youve found VFR.

That and forecast products can and have been wrong, very wrong and I don't want to get up there and discover that first hand .

de727ups

"climbing in icing conditions, generally speaking attempting to out climb the ice is a bad plan for light GA aircraft as it generally cannot be done"

I agree.

Always leave yourself and out and, if you start getting ice, use it. That said, I think you can do a lot during the winter months. You aren't a seasoned IFR pilot until you've seen, and dealt with, icing conditions.

patton33

yes, what it all comes down to with icing and light aircraft is ALWAYS having an out.

DamonMeyer

I'll second that emotion. And the out should not be a climb, e.g. to the warmer temps above indicated by the freezing rain you've encountered. For ice potential in a small plane, the out should be a quick 180 or a good margin below of air between the feezing layer and the ground.

snippercr

Thanks for all the input so far guys.

So riddle me this...I wanted to go IFR today. Temp/dew was 02/01 visiblity was 2sm, cig was ovc at 600 feet. Lovely weather to gather some actual instrument time!
However, using the 2deg/1000 feet, that means once I climb 1000 feet, I will be at the freezing level. Does this constitute known icing conditions both in the aspect of safety and legality?
aviationweather doesnt show any air/sigmets for icing over the area nor where there any pireps of any type of icing.
What do I Make of that? Is it best that I didnt go or given the lack of pireps/forcasted ice should I have gone as long as I had safety outs (a general consensus here).
Edit: Incidentally I checked the winds aloft and temps showed +C all the way up to over 6000 feet. I am confused... would this be a temperature inversion since its actually warmer above us? See previous metar.

patton33

I usually use an upper air sounding to determine temp/dp spread aloft. in regards to the ceiling info you posted, especially if you have little to no time in actual, establish a personal minimum for yourself that AT LEAST meets the minimums of the highest circling approach.