Tips For Flying in ICE

[pilotpat]

Excellent question Alin 'cuz I wouldn't know how to answer it. What is at or near freezing?? In my airplane, we turn engine heats on anytime our ram air temp is +10C or less in visible moisture.

 

[Morettis]

Anything +4*C or less in visable moisture is considered icing conditions

 

[Alin10123]

Anything +4*C or less in visable moisture is considered icing conditions

So that means if the forecast is for -6 degrees @ 3000 and IMC starts at 3000. Then i should be ok to go in a plane that is not approved for known icing?

 

[Geronimo4497]

Um, not if you are planning on going above 3000 ft. Do yourself a big favor and respect the icing conditions if present. A 172 or any other non-known ice airplane has no business flying around in those conditions. If you hear 'forecast icing conditions' you should not be out there. Period.

 

[pilotpat]

Um, not if you are planning on going above 3000 ft. Do yourself a big favor and respect the icing conditions if present. A 172 or any other non-known ice airplane has no business flying around in those conditions. If you hear 'forecast icing conditions' you should not be out there. Period.

Perfect point for aircraft limited by the AFM not to fly in icing conditions. Simple. Its kind of like when I was doing the CFII thing: I'd tell my students that the ticket didn't mean they go looking for clouds to fly through in the school's battered 172's. (off topic yet relevant: You get your Instrument Rating in a Katana C1, which isn't even approved for IMC, but you're still proficient, can you fly in clouds?) It means that they have simply proven to PTS standards that they can fly basic attitude instruments, hold, and shoot an approach...and maybe not all that good either, but at least to the standards. Just because you have a TKS system in your shiny new Mooney doesn't mean you blast into SLD's!

And Alin, regarding your earlier post, it doesn't matter if the cloud deck is only 500' thick. You would still be violating FAR's climbing through it if there's any kind of ice accretion in a non-certified aircraft. If the overcast is at 3000' but you're in the clear at 2000', even though there's icing in clouds and its -6C, then you would be fine. Until the precip begins...

 

[Alin10123]

And Alin, regarding your earlier post, it doesn't matter if the cloud deck is only 500' thick. You would still be violating FAR's climbing through it if there's any kind of ice accretion in a non-certified aircraft. If the overcast is at 3000' but you're in the clear at 2000', even though there's icing in clouds and its -6C, then you would be fine. Until the precip begins...

Ah i see. Is there a point to where the cloud layer would already be frozen beyond the ability to accumulate on your aircraft? For example, if -10 degrees means that the clouds are mostly tiny ice crystals instead of moisture, does that count as known icing? I'm not trying to see how far i can tread without actually breaking a FAR, but i just want to sort of get an idea of everything without actually intentionally flying into icing to try it.

 

[avbug]

-10 degrees is where you're going to pick up some of your heaviest icing.

It's best not to make assumptions with ice.

Ice, and supercooled liquid water, can be found down to -40 degrees.

I've picked up some surprisingly large amounts of ice in narrow layers before, with substantial amounts of liquid water and temperatures well below freezing.

Over the past few months, I managed to find areas in the desert that produced up to 3" of ice in several passes through the same area within a fairly narrow altitude band.

You might be surprised.

So that means if the forecast is for -6 degrees @ 3000 and IMC starts at 3000. Then i should be ok to go in a plane that is not approved for known icing?

Absolutely not.

Icing conditions can exist with temperatures above freezing. There is no hard fast rule as to when that number begins. Many companies will state five or ten degrees above freezing to initate anti ice in the presence of visible moisture, all you need to know is that if it's freezing conditions (plus a margin above that) and there's visible moisture, you need to stay out if your aircraft isn't certified for flight into known ice. Even if it is, conditions can exist that exceed the capabilities of your aircraft, and even if they don't exceed the capabilities of your aircraft, they may exceed your capabilities (your airplane when iced is a different airplane, and different rules apply to flying it).

Stay out of ice.

 

[pilotpat]

For example, if -10 degrees means that the clouds are mostly tiny ice crystals instead of moisture, does that count as known icing? I'm not trying to see how far i can tread without actually breaking a FAR, but i just want to sort of get an idea of everything without actually intentionally flying into icing to try it.

We treat all IMC flying at temps down to -30C as possible icing and keep the engine heats on. If we see ice forming on the windscreen, like on the great functioning windshield wipers :smash: ...then we'll turn on the wings as well. I had one excursion into "unforcast" ice in a 172. Never again. And I mean NEVER! Things went downhill real quick. Including my RPM's, Airspeed, and my stomach.

 

[414Flyer]

0c is more of a melting point for ice, then a freezing point for liquid water. Supercooled water can be found from below 0c all the way down to -40 in rare conditions as avbug mentioned.