Is this Known Icing?

[genna]

So, i'm looking at current Airmet Zulu here at KDMW and this is what it states:

Ice between freezing level and 12,000 feet. Freezing level 2,000 feet to
7,000 feet. Conditions continuing beyond 5pm EDT (21Z) ending 8pm EDT

The METAR is overcast 5000 VFR and forcast stays pretty much that until tomorrow.

Skew-T also confirms that the temp and dew meet around 5000ft around the area and forcasted to actually spread appart later this evening

I was going to go and shoot some approaches later this evening (22Z) at about 3-3500ft.

PIREPS report ICE 060 and higher

Is this known icing or not? I'm confused.

P.S. i forgot to add the Temp at the airport is +1C and freezing level is around 300AGL

 

[RotorDude]

So, i'm looking at current Airmet Zulu here at KDMW and this is what it states:

Ice between freezing level and 12,000 feet. Freezing level 2,000 feet to
7,000 feet. Conditions continuing beyond 5pm EDT (21Z) ending 8pm EDT

The METAR is overcast 5000 VFR and forcast stays pretty much that until tomorrow.

Skew-T also confirms that the temp and dew meet around 5000ft around the area and forcasted to actually spread appart later this evening

I was going to go and shoot some approaches later this evening (22Z) at about 3-3500ft.

PIREPS report ICE 060 and higher

Is this known icing or not? I'm confused.

It's not icing if you stay out of clouds (or other visible moisture). So I can't see why you can't shoot approaches. However, do check for icing and be ready to scoot back if you see any (e.g. scattered stuff).

 

[N801BH]

It's not icing if you stay out of clouds (or other visible moisture). So I can't see why you can't shoot approaches.

You can ice it up and not be in the soup..... Don't axe how I know...

 

[Alexb2000]

Pireps from who? I say that because I have found that jets with their ram rise usually report icing higher (colder) than I see it at slower speeds. For example the other day they were reporting icing at 16-25, when I was seeing it at 11K stopping when I reached positive temps at 10K. In your case VFR and under 5,000 I would fly no question. The only thing I would be sure of is that there isn't an inversion and a chance of freezing rain.

 

[poadeleted20]

It's not icing if you stay out of clouds (or other visible moisture). So I can't see why you can't shoot approaches.

Agreed, although I'd say it's not "known icing conditions" to be more in line with the FAA letter on point. Did you also look at the icing probability charts in the FIP under the Forecast/Icing tab on aviationweather.gov? I find that to be an excellent tool to help make these decisions.

 

[James331]

If the ceiling stays there and you don't have any precip, you should be good.

 

[genna]

It's not icing if you stay out of clouds (or other visible moisture). So I can't see why you can't shoot approaches.

I get that. I'm not so much worried if i get any ice. I am pretty sure i won't, and if i do, i will be right over a clear airport, so there is a pretty good out.

Question is: does it legaly constitutes Known Icing if i am inside Airmet Zulu?


Visual moisture is no longer FAA definition of KI as far as i can tel

 

[genna]

Pireps from who? I say that because I have found that jets with their ram rise usually report icing higher (colder) than I see it at slower speeds. For example the other day they were reporting icing at 16-25, when I was seeing it at 11K stopping when I reached positive temps at 10K. In your case VFR and under 5,000 I would fly no question. The only thing I would be sure of is that there isn't an inversion and a chance of freezing rain.

Jets, of course

 

[poadeleted20]

Question is: does it legaly constitutes Known Icing if i am inside Airmet Zulu?


Visual moisture is no longer FAA definition of KI as far as i can tel

I think you need to read the Bell letter to which I referred above, so here's the link to it. Take your time and read it slowly and carefully, as there's a lot there, and the details are important. Note in particular that "known icing" is not the same as "known icing conditions", and it is flight into known icing conditions which is the big issue here.

 

[bobmrg]

I get that. I'm not so much worried if i get any ice. I am pretty sure i won't, and if i do, i will be right over a clear airport, so there is a pretty good out.

Question is: does it legaly constitutes Known Icing if i am inside Airmet Zulu?


Visual moisture is no longer FAA definition of KI as far as i can tel

The legal standard is now "what a prudent pilot would do in the same circumstances," so IMHO it boils down to this: Get into icing trouble and require ATC assistance...busted. Pick up some ice, get out of the icing conditions on your own...golden. Nothing to do with Airmet Zulu other than what conclusions a prudent pilot would draw from it and other sources.

Report icing, if encountered, for the benefit of other pilots, and take action to get out of the icing conditions ASAP for the sake of your ticket.

Bob Gardner

 

[genna]

Agreed, although I'd say it's not "known icing conditions" to be more in line with the FAA letter on point. Did you also look at the icing probability charts in the FIP under the Forecast/Icing tab on aviationweather.gov? I find that to be an excellent tool to help make these decisions.

I am inclined to agree, but wanted opinions.

Forcast Icing: no ice at 3000, yes ice at 5000+

There is a small inversion starting 3000 to about 9000 of a few degrees. Never getting above -5C

No chance of precip forcasted

 

[RotorDude]

I get that. I'm not so much worried if i get any ice. I am pretty sure i won't, and if i do, i will be right over a clear airport, so there is a pretty good out.

Question is: does it legaly constitutes Known Icing if i am inside Airmet Zulu?


Visual moisture is no longer FAA definition of KI as far as i can tel

Legally (in recent interpretations) it's considered "known icing" if at least one of these conditions exists:
1. You have fresh icing pirep for the airspace you plan to fly in; or
2. A "reasonable pilot" would assume, based on the known pre-flight data, that there would be icing in the airspace you plan to fly in.

In your case, you have none (#2 fails because a reasonable pilot would know there can't be ice outside visible moisture), therefore you are good to go, with the caveat that if anything changes, e.g. you spot even a tiny buildup, you land.

 

[genna]

Thanks guys! I feel better now

 

[Henning]

So, i'm looking at current Airmet Zulu here at KDMW and this is what it states:

Ice between freezing level and 12,000 feet. Freezing level 2,000 feet to
7,000 feet. Conditions continuing beyond 5pm EDT (21Z) ending 8pm EDT

The METAR is overcast 5000 VFR and forcast stays pretty much that until tomorrow.

Skew-T also confirms that the temp and dew meet around 5000ft around the area and forcasted to actually spread appart later this evening

I was going to go and shoot some approaches later this evening (22Z) at about 3-3500ft.

PIREPS report ICE 060 and higher

Is this known icing or not? I'm confused.

P.S. i forgot to add the Temp at the airport is +1C and freezing level is around 300AGL

The PIREP I'm pretty sure seals it as Known Icing Conditions, however if you can remain VMC for your practice, you are legal and fine as you won't enter them.

 

[James331]

I think you need to read the Bell letter to which I referred above, so here's the link to it. Take your time and read it slowly and carefully, as there's a lot there, and the details are important. Note in particular that "known icing" is not the same as "known icing conditions", and it is flight into known icing conditions which is the big issue here.

So you're saying flying into a airmet Zulu, with high ceilings and no precip in the area of flight, currently or forecast, is a violation?



Looks like at least two folks here are getting by

 

[Henning]

So you're saying flying into a airmet Zulu, with high ceilings and no precip in the area of flight, currently or forecast, is a violation?

No, he's saying the opposite, stay in VMC and the conditions don't exist, so all is just chilly...

 

[James331]

No, he's saying the opposite, stay in VMC and the conditions don't exist, so all is just chilly...

So basically just the same thing I said clearly in one sentence

 

[poadeleted20]

Legally (in recent interpretations) it's considered "known icing" if at least one of these conditions exists:
1. You have fresh icing pirep for the airspace you plan to fly in; or
2. A "reasonable pilot" would assume, based on the known pre-flight data, that there would be icing in the airspace you plan to fly in.

This mashes together the definitions if the separate terms "known icing" andi "known icingi conditions". The two terms are not synonymous, and should not be confused with each other. Please read the Bell letter in its entirety to get understand the FAA's position on this issue.

In your case, you have none (#2 fails because a reasonable pilot would know there can't be ice outside visible moisture), therefore you are good to go, with the caveat that if anything changes, e.g. you spot even a tiny buildup, you land.

Agreed, because with no clouds or precip forecast at your altitude, you are not in "known icing conditions".

 

[Henning]

The FAA really needs to start a better educational campaign on this.

 

[poadeleted20]

No, he's saying the opposite, stay in VMC and the conditions don't exist, so all is just chilly...

It is possible to be in known icing conditions and to pick up icing while in VMC, so that is not quite accurate. Visible moisture includes things besides clouds, and visibility may well be above VMC mins outside clouds but in precip that could freeze onto your airplane.

 

[N801BH]

It is possible to be in known icing conditions and to pick up icing while in VMC, so that is not quite accurate. Visible moisture includes things besides clouds, and visibility may well be above VMC mins outside clouds but in precip that could freeze onto your airplane.

Yup...... BTDT....

 

[RotorDude]

This mashes together the definitions if the separate terms "known icing" andi "known icingi conditions". The two terms are not synonymous, and should not be confused with each other. Please read the Bell letter in its entirety to get understand the FAA's position on this issue.


Agreed, because with no clouds or precip forecast at your altitude, you are not in "known icing conditions".

Yes, I am familiar with that letter, but still consider the above two points my "working interpretation" of "known icing" for the purpose of go/nogo in a non-FIKI aircraft. My own rules would keep me (reasonably) safe even if there were no FAA and no interpretation letters.
(And I guess "safety risks" include enforcement actions. )

 

[Henning]

It is possible to be in known icing conditions and to pick up icing while in VMC, so that is not quite accurate. Visible moisture includes things besides clouds, and visibility may well be above VMC mins outside clouds but in precip that could freeze onto your airplane.

A person can't even defend you without getting corrected.

 

[poadeleted20]

Yes, I am familiar with that letter,...

Good, I'm just hoping the OP and anyone else unfamiliar with it also reads it thoroughly.

 

[genna]

Good, I'm just hoping the OP and anyone else unfamiliar with it also reads it thoroughly.

i'm staying VMC, not IFR rated and i wouldn't fly into IMC in this weather for icing reasons, that would be flying into Known Icing without a question.

I read the letter.. I understand the difference between Known Ice and Known Icing Conditions. In this case, only the existence of the "Conditions" is in question since PIREPs(KI) are well outside my intended altitude.

I think i'm pretty clear that I will be ok legaly.

The confusion is this: Airmet Zulu exists, and i am flying into it.

A reasonable pilot, looking at the entire picture of the weather should reasonably conclude that I will not encounter ice where i am going.

However, if i do encounter ice, then i validate the Airmet Zulu's assertion that icing existed at what i though was safe altitude and the fact that Arimet exists IS a known icing condition and i flew into it.

Basically if all goes well, i was legal, if i get into ice, i was illegal by definition inspite conditions being the same... This is what i am getting from the FAA interpretation. Seems pretty nutty. It seems like saying: if i drive drunk, as long as i don't get into an accident, not illegal.

 

[genna]

Maybe "Legally" was a wrong choice of a word. FAR does not talk about Known Icing Conditions. But you can get into trouble for it nevertheless

 

[Henning]

i'm staying VMC, not IFR rated and i wouldn't fly into IMC in this weather for icing reasons, that would be flying into Known Icing without a question.

I read the letter.. I understand the difference between Known Ice and Known Icing Conditions. In this case, only the existence of the "Conditions" is in question since PIREPs(KI) are well outside my intended altitude.

I think i'm pretty clear that I will be ok legaly.

The confusion is this: Airmet Zulu exists, and i am flying into it.

A reasonable pilot, looking at the entire picture of the weather should reasonably conclude that I will not encounter ice where i am going.

However, if i do encounter ice, then i validate the Airmet Zulu's assertion that icing existed at what i though was safe altitude and the fact that Arimet exists IS a known icing condition and i flew into it.

Basically if all goes well, i was legal, if i get into ice, i was illegal by definition inspite conditions being the same... This is what i am getting from the FAA interpretation. Seems pretty nutty. It seems like saying: if i drive drunk, as long as i don't get into an accident, not illegal.

If you are not in visible moisture or at risk of visible moisture falling on you from above, then "conditions" is not in doubt, you're not in them.

 

[petrolero]

Good, I'm just hoping the OP and anyone else unfamiliar with it also reads it thoroughly.

I read it. Thanks for posting the link.

As far as the OP goes, even before reading the letter, I'd say he'd be OK legally and physically as long as he is clear of visible moisture. The AIRMET only applies where icing conditions exist. It's not some kind of blanket prohibition to flight for all non-FIKI aircraft. The letter confirms this.

In general, the letter adds some nuance to what the FAA will consider during an investigation into an actual icing encounter but who wants to get to that point in the first place?

People can swear up and down that simply flying into visible moisture that is below freezing is not unreasonable and yet every pilot is taught that those are the minimum conditions necessary for ice formation. So is it really reasonable to fly into them? Maybe. Some of us might read the letter and say "well it's reasonable as long as one checks all the sources listed in the letter and comes to the opinion that icing conditions are not 'known' at that time." Again... maybe.

But if you fly into visible moisture that is below freezing and you do encounter ice - you better be willing to defend your actions before the FAA and have the FAA go back and second-guess your decision-making. That is not a happy scenario for any pilot. Did you maintain any written record of how you formed your decision? Even if you did, would a "reasonable pilot" find that icing conditions shouldn't have been "known?" That's a scary standard to me - perhaps because I am not well-versed in FAA and NTSB case law.

And that's why I don't care what the letter says... I sincerely try to avoid freezing clouds in all but the most benign of circumstances. All this "reasonable pilot" mumbo jumbo is, to me, a last resort, not something on which to base pre-flight decisions.

Call me a pansy, but that's the way I approach this subject today.

 

[poadeleted20]

i'm staying VMC, not IFR rated and i wouldn't fly into IMC in this weather for icing reasons, that would be flying into Known Icing without a question.

One last time -- this is not "Known Icing". Please, please, please read the Bell letter carefully.

I read the letter.. I understand the difference between Known Ice and Known Icing Conditions.

If that were true, you wouldn't have written the sentence quoted above.

In this case, only the existence of the "Conditions" is in question since PIREPs(KI) are well outside my intended altitude.

Well, you got that part right.

I think i'm pretty clear that I will be ok legaly.

Agreed.

The confusion is this: Airmet Zulu exists, and i am flying into it.

A reasonable pilot, looking at the entire picture of the weather should reasonably conclude that I will not encounter ice where i am going.

However, if i do encounter ice, then i validate the Airmet Zulu's assertion that icing existed at what i though was safe altitude and the fact that Arimet exists IS a known icing condition and i flew into it.

You were close. Yes, the fact that all available information taken as a whole available would lead a reasonable and prudent to believe that it was not likely that icing would adhere to the plane means that known icing conditions do not exist. However, the Airmet is irrelevant in determining whether known icing exists -- Airmet Zulus are only relevant to determining whether known icing conditions exist. For "known icing" to exist, it would take actual first-hand observation of icing occurring or PIREPS of icing occurring.

Basically if all goes well, i was legal, if i get into ice, i was illegal by definition inspite conditions being the same...

No. If you stumble into icing despite the fact that known icing conditions as defined in the Bell letter did not exist when you started, you have not violated the regulations unless you don't do your best to get out of the icing.

This is what i am getting from the FAA interpretation. Seems pretty nutty.

Then I think you need to read the letter again more carefully.

It seems like saying: if i drive drunk, as long as i don't get into an accident, not illegal.

It doesn't.

 

[Henning]

Basically if all goes well, i was legal, if i get into ice, i was illegal by definition inspite conditions being the same... This is what i am getting from the FAA interpretation. Seems pretty nutty. It seems like saying: if i drive drunk, as long as i don't get into an accident, not illegal.

Mmmmm, not quite. It's more like arguing "Just because there is booze in the car doesn't mean I'm driving drunk", which is true. Even if the seal is busted, unless you blow a DUI, you only get an Open Container ticket. If you don't smell like booze, they don't typically give you that. "Why do you have an open bottle?" I'm heading to a BYOB party and I just grabbed it from home, I don't drink enough to buy a new bottle all the time just to take somewhere and make a couple drinks from." Then they just let you get on your way.

 

[poadeleted20]

Maybe "Legally" was a wrong choice of a word. FAR does not talk about Known Icing Conditions. But you can get into trouble for it nevertheless

Actually, it's the wording in the Limitations section of your POH which is the issue, and that limitation says "known icing conditions". The regulation (91.9) merely says you are not permitted to violate any POH limitations on your aircraft. That's why the lawyers are making such a big thing about the difference in meaning between the two terms.

 

[poadeleted20]

Mmmmm, not quite. It's more like arguing "Just because there is booze in the car doesn't mean I'm driving drunk", which is true. Even if the seal is busted, unless you blow a DUI, you only get an Open Container ticket. If you don't smell like booze, they don't typically give you that. "Why do you have an open bottle?" I'm heading to a BYOB party and I just grabbed it from home, I don't drink enough to buy a new bottle all the time just to take somewhere and make a couple drinks from." Then they just let you get on your way.

Which is why various states have separate laws regarding DUI and having an open container -- they don't have to prove DUI to bust you for "open container", just that the container was there and open. And the fact that you were legally sober is no defense.

 

[Henning]

Which is why various states have separate laws regarding DUI and having an open container -- they don't have to prove DUI to bust you for "open container", just that the container was there and open. And the fact that you were legally sober is no defense.

What does that have to do with this? It was a comparison in analogies, not a lesson on law and alcohol.

 

[genna]

It turned out to be a beautiful, clear and warmer-then-expected evening by the time i took off.

thank you all for your help

 

[Palmpilot]

Actually, it's the wording in the Limitations section of your POH which is the issue, and that limitation says "known icing conditions". The regulation (91.9) merely says you are not permitted to violate any POH limitations on your aircraft. That's why the lawyers are making such a big thing about the difference in meaning between the two terms.

That's the wording in Cessna POHs. The Piper POHs I have just say that the airplane is approved for "non icing" operations.