What, legally, are "Known Icing Conditions"?

That's not known icing, that is possible icing, not even probable icing. That will keep you grounded much of the winter in the northern latitudes, though it will certainly keep you legal and safe, in respect to icing, at least. I certainly don't find fault with you choosing this conservative approach, but personally I find it a little too restrictive.

I'm pretty amazed with how many pilots who are typically conservative will make this same statement.

Not pointing you out personally, Grant. :)

I've talked to at least 10 pilots (over the last three or four years) who were busted for flying into known icing conditions in an aircraft without a certified ice protection system (under Part 91).

Without going into too many personal details, could you go into the circumstances? Did they make a scene, or did they just happen to land in front of an inspector doing ramp checks with a load of ice, etc.? I'm curious.
 
Can I fly into "unknown icing conditions" rather than "known icing conditions" without de-icing equipment? Then if I don't ask about icing conditions then it is legal for me since I don't know.
No. One of the FAA letters Dr. Bruce linked to reminds us that 14 CFR 91.103 specifies that "each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight. This information must include...for a flight under IFR or a flight not in the vicinity of the airport, weather reports and forecasts...."

So ignorance of the weather puts you in violation of 14 CFR 91.103.
 
Yes, these are two different temperatures. The static air temperature is much different than the total air temperature. The total temperature factors in adiabatic compression which does keep the immediate leading edges warmer than the static air temperature (the temperature you'd record on a thermometer if it were at rest). Most pistons don't have a total air temperature sensor...they only have the outside air temperature sensor (which is an immersion thermometer that has it's own set of issues). It is impossible to collect ice with a static air temperature greater than 0°C. Forecasts for ice are based on static air temperature.
Two questions then:

1. Are the effects of adiabatic compression significant in a piston single traveling at 150 kts?

2. Under what conditions, if any, will a properly calibrated immersion thermometer installed in such an airplane read higher than the static air temperature?
 
I'm an IR PPl with 300 hrs. I fly a non-FIKI plane. I live in the south, so icing is only rarely a concern; even in the winter, it's pretty typical to not have to worry about icing when planning a short flight.

Not trying to be a gotcha sniper that's seems so prevalent on boards like these, but wanted to share a specific experience in response to your statement.

I too live in the South (Little Rock) and got one of my worst icing incidents a couple of years ago when I was near 300hrs of experience on a winter day with no forecasted icing at all -- and I was doing a "short flight" (45 mins).

'Looked at ADDS and saw nothing. Called the briefer on the way to the airport and he too saw nothing. I want to say surface temps were around 42-44F and the air above was not overly cold, per the ADDS and SkewT products. Also, there were no PIREPs -- and it was around mid-day / I wasn't the first one venturing off into the unknown.

Within about 30-45 mins, I take off and enter the clouds around 1500' and climb out on top around 8000'. When I break out on top, I can't see out of the plane due to ice all over it. It took about 15-20 mins in the sun for it to melt off. Simultaneous to me making it on top, the Center freq lights up with multiple PIREPs of icing all around me. The forecasted 9000' temps from the ADDS winds product turned out to be 17F instead of the 30F forecasted. An upper-level air mass was coming in from the North at a substantially faster rate than all the models had predicted... i.e. It got much colder much quicker than the meteorologists, or their computers, expected.

So I call Center and tell them the situation. They are most accommodating and ask what I want to do since the icing PIREPS were popping up in all directions by other surprised pilots like me. I'm close to my destination, which was reporting around 1500' cielings, and just requested an expedited descent through the layer. They ask me how close I wanted to get before starting down. I do a little math so as to achieve around 2000-3000fpm through the layer and come up with a distance so as to not hang out under it too long (in case super-cooled stuff was falling out the bottom). On the dot to that distance, they clear me to descend. I break out the bottom with minimal ice, finish the approach, land, and logged one of those 45 mins of experience that really was more like 200hrs of experience.

Moral: There are classic heavy icing places, like East of Seattle, but icing can pop up anywhere -- with a vengeance -- and the forecasts even just 1 hour out are just guesses....Even in areas where icing isn't a daily thing.
 
Thing that annoys me with the FAA known icing conditions is in the difference between FIKI and 'Full-Deice'.

You know what the difference is between a FIKI certified airplane and a non-certified 'full de-ice' 310 or Baron?

An $8-10k hot plate on the windscreen and even if you go out and buy one, you can't retro-actively certify your airplane for FIKI if it didn't leave the factory certified.
 
People drive while drunk and a lot of them don't have an accident and don't get caught.


We should take the licenses from all that have possibly been drinking, as opposed to those known to be drunk?

Temp and Visible Moisture give you the possibility....

Pireps are about the best you can get for Known Icing. Forcasted, I think they would certainly hang you if something happened (assuming you live through it.)
 
Without going into too many personal details, could you go into the circumstances? Did they make a scene, or did they just happen to land in front of an inspector doing ramp checks with a load of ice, etc.? I'm curious.

Also, when were these violations. I'm guessing before the 2009 letter of interpretation, or the guys scott talked to were making very bad decisions.
 
A friend of mine must have been flying with the most paranoid pilots who ever took to the skies. One was even an aviation attorney. She tells the story that she was flying with these guys as a passenger, in IMC (somewhat turbulent IMC at that), when they started picking up ice. She asked the PF why he didn't just call up ATC and tell the controller they were picking up ice and needed a change of altitude. Both pilots quickly answered, no no no, we can't do that, if we do that it's an admission that we were flying in "known icing conditions" and we'll get busted. So they kept flying along, not a peep, all the while accreting ice all over the airframe. I forget whether they eventually got out of the clouds and lost the ice, or whether they landed with it.

Idiots. :loco:

Okay, for the record, not all aviation attorneys are that stupid.
 
Okay, for the record, not all aviation attorneys are that stupid.
Read again -- it was the pilots, not the aviation attorney, who were being stupid. The attorney was the one who asked them why they didn't get out of the ice. And for the record, ATC will not report you to the FSDO just for reporting ice or even asking to get out of it ASAP.
 
Read again -- it was the pilots, not the aviation attorney, who were being stupid. The attorney was the one who asked them why they didn't get out of the ice.



A friend of mine must have been flying with the most paranoid pilots who ever took to the skies. One was even an aviation attorney.

No, I think this means that one of the pilots was an aviation attorney.
 
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Several pieces of equipment and a whole lot of flight testing.
Not really. Just the one piece of equipment - the hot plate. Yes, there was testing for the certification, but the airframe and equipment (minus that one item) are the same.
 
Flying in ice because you're afraid ATC will report you? There can't be pilots that stupid...can there? Thats like flying into a mountain because you don't want to bother ATC and ask for a heading change.

Please god let this story not be true.
 
Remember the only thing infinite besides the universe.
 
No, the letter at Bruce's link says "a" where the quote says "take"

That's a bit better. Still, horrible to start with such a long dependent clause. I guess that's legalese.
 
That's a bit better. Still, horrible to start with such a long dependent clause. I guess that's legalese.

One makes sense, and the other does not, so I would say that it's a lot more than "a bit" better. I am not, however, expressing an opinon on the Chief Counsel's writing style.
 
One makes sense, and the other does not, so I would say that it's a lot more than "a bit" better. I am not, however, expressing an opinon on the Chief Counsel's writing style.

The correct version makes sense, but is written in legalese. A LOT better would have been to turn the two parts of the sentence around, in this way:

"Known icing conditions exist if the composite information indicates to a reasonable and prudent pilot that he or she will be operating the aircraft under conditions that will cause ice to adhere to the aircraft along the proposed route and altitude of flight."

We're not German, after all, and getting the subject and verb a bit earlier on is more logical and natural to speakers of English.

[If the Chief Counsel's writing style were used, that would have read, "More logical and natural to speakers of English, and since we're not German, after all, is getting the subject and verb a bit earlier."] :lol:
 
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I'm a bit like this guy when it comes to "standards of spelling," or speaking, or writing, for that matter.

Oh, I know I'm a hypocrite, but at least I'm trying!

 
The correct version makes sense, but is written in legalese. A LOT better would have been to turn the two parts of the sentence around, in this way:

"Known icing conditions exist if the composite information indicates to a reasonable and prudent pilot that he or she will be operating the aircraft under conditions that will cause ice to adhere to the aircraft along the proposed route and altitude of flight."

We're not German, after all, and getting the subject and verb a bit earlier on is more logical and natural to speakers of English.

[If the Chief Counsel's writing style were used, that would have read, "More logical and natural to speakers of English, and since we're not German, after all, is getting the subject and verb a bit earlier."] :lol:

I like reading stuff that is written the way you rewrote that sentence.
 
I'm a bit like this guy when it comes to "standards of spelling," or speaking, or writing, for that matter.

Oh, I know I'm a hypocrite, but at least I'm trying!


:rofl:

I really like that guy!

Most of the time, I restrain myself from correcting people's spelling, punctuation, etc. on line, but what gets me is the apparent lack of proofreading in print publications. It didn't used to be this way. And of course, it's always the type of error that spelling-checking software can't catch!
 
No, I think this means that one of the pilots was an aviation attorney.
Correct. The non-flying pilot i.e. right seater.

At least that's my understanding of the story. My friend was not instrument rated at the time, so it seems unlikely she'd be in the right seat. For clarity then: my friend asked them why they didn't ask for a change of altitude, and both of them said no, for the reason given.

I wasn't there, but my friend is usually quite reliable about such things, and has told the story several times in my presence, and the details have always been the same.
 
Not trying to be a gotcha sniper that's seems so prevalent on boards like these, but wanted to share a specific experience in response to your statement.

I too live in the South (Little Rock) and got one of my worst icing incidents a couple of years ago when I was near 300hrs of experience on a winter day with no forecasted icing at all -- and I was doing a "short flight" (45 mins).
Thanks for sharing your experience. I live along the Gulf coast. It's not unusual to go all winter without a freeze. Also not uncommon to have days in January where the sky is clear and the high temp is in the 60s. So a lot of times, even in the middle of winter, icing is exactly as likely as in the middle of July. Since those mild, clear days are more likely to find me flying, that's what I had in mind when I said icing is only rarely a concern.

But your point is well-taken. Even when the forecast seems to clearly indicate icing is unlikely, it can still come into play, and I appreciate hearing about your experience. Icing situations are definitely one of those "I don't really know how much I don't know" topics. The trick is to get smart and experienced without making a stupid mistake and getting killed.
 
I like reading stuff that is written the way you rewrote that sentence.

Sentences, re-written in the fashion in which I re-wrote the initial sentence, their primary importance being, one would hope, in the simple and clear message they purvey, are perhaps best, considering the grammatical simplicity of putting the subject and verb nearer the front of the sentence, written in the un-re-written way I re-wrote that first sentence.
 
:rofl:

I really like that guy!

Most of the time, I restrain myself from correcting people's spelling, punctuation, etc. on line, but what gets me is the apparent lack of proofreading in print publications. It didn't used to be this way. And of course, it's always the type of error that spelling-checking software can't catch!

He's really funny. If you want to see more of him, goto youtube and type "David Mitchell." This is from the "David Mitchell's Soapbox" rants series.
 
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