C172 into Known Icing?

JohnSBA

JohnSBA

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JohnSBA
I've been discussing with a pilot friend something I heard about. A highly skilled CFII repeatedly flew into icing in a C172 shooting approaches. Moderate icing at 3k'AGL, thawing at 1k'AGL.

My friend says it's a great way to learn how an aircraft handles with ice and would do it for the experience. I say there are excellent reasons that the C172 POH prohibits flight into known icing. Since the CFII survived it, my friend says no worries. My impression from reading is that icing can be different every time (even on the same flight), and unpredictably lead to unrecoverable uncontrolled flight into terrain.

Does anyone here have definitive knowledge or experience on this topic? I'm not interested in starting (or finishing) an argument. What I'm hoping is that someone can shed more light on the notion of flight into icing with a non-rated but very stable platform like the C172.
 
The short answer is that "most" of the time you can do it; if you can melt it off then there will be no problems. With all that said, "You never know how fast it will accumulate, until you are in it!" If you get into a situation where it starts coming on fast then you could get yourself into a pickle and quick.
 
I got caught in ice - definitely not forecast or planned - in a C172RG. I probably ended up with 3/4" before I got it to an airport. Made a pretty much normal approach but left the gear up till fairly short on final and did not use flaps. It flew OK. The windshield went opaque and was lucky to have two "spy" holes of maybe 5" diameter to peer through. Not an experience I ever had any interest in repeating, though I felt no great danger or threat. I got it on the ground as quickly and deliberately as possible. Shot an ILS approach to a non-towered airport.

I was told by the owner that that airplane had carried 2" of ice but I have no knowledge and no interest in checking it out.

I've never felt a need to see how an airplane that was not supposed to be in ice would fly in ice, as I figured I'd try to not get in or if caught would try to get out. Would it help me to know that 2" or clear ice would cause a stall? If I had the 2", it wouldn't matter and I'm not going to stay in ice to get the 2" to see what I can get away with.
 
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It is my policy that you should never purposely get into icing in an airplane not equipped to deal with it. Really, you are asking for trouble. That said, if you want to do it there are better and worse ways to do it.

Icing at 3k and thawed at 1k isn't nearly enough altitude of above freezing, and is definitely a worse way to do it if you're going to. Find a day with freezing level of say 5-10k and icing above that. Much better.

But my suggestion is avoid icing like the plague.
 
JohnSBA said:
I've been discussing with a pilot friend something I heard about. A highly skilled CFII repeatedly flew into icing in a C172 shooting approaches. Moderate icing at 3k'AGL, thawing at 1k'AGL.

My friend says it's a great way to learn how an aircraft handles with ice and would do it for the experience. I say there are excellent reasons that the C172 POH prohibits flight into known icing. Since the CFII survived it, my friend says no worries. My impression from reading is that icing can be different every time (even on the same flight), and unpredictably lead to unrecoverable uncontrolled flight into terrain.

Does anyone here have definitive knowledge or experience on this topic? I'm not interested in starting (or finishing) an argument. What I'm hoping is that someone can shed more light on the notion of flight into icing with a non-rated but very stable platform like the C172.
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I would strongly advise against flying ANY non-K aircraft in known ice because it is both very dangerous and against FARs.

Go to a simulator and safely see how you handle things while VMC in a simulated ice build-up for your selected aircraft.
 
I have no type-specific experience in 172s and ice, but I do have what I consider considerable experience flying in icing conditions. It is absolutely true that the severity, rate of accumulation, and even type of ice can vary widely in the same general area. Based on the information provided, I personally would consider the CFII in question to be a danger to himself and others, but I have no special knowledge of the area and conditions at the time. I could see in a static stratus layer with little lifting it might be possible to have relatively consistent and somewhat predictable accumulation rates.

Regardless, it is a clear violation. :nono:
 
Yeah, there's an out. But if the temp gets down to 34 at the surface, and the fuel gets cold soaked, you'll still have a substantial ice load when you try to flare. And it is a violation.
 
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I picked up a good amount on the loc approach into Decatur IL many years ago. I could see it on the thermometer stem and just a little on the leading edge of the wings. I still landed no flaps and didn't drop the gear till approaching the fence. I had to lockout the auto gear extension to do that. The landing was Uneventful. When I got out of the aircraft I saw a good 2" of ice stuck to the leading edge of the stabilator. That was a very solemn site.

Have since learned that in the Arrow, the stabilator ices first then stalls. When the stabilator stalls the Arrow tends to go nose down which puts negative loading on the wing and they basically break off.

I avoid ice.
 
you're flying an airplane not certified for flight into known icing. You might get away with it until the accident report is published after accumulating ice so fast that the plane practically stops. Don't do it!
 
Most people who die in icing realted crashes have experienced icing before the day they crashed...Moral to the story, don't launch a 172 into known icing and if you encounter it-get the hell out of it.
 
I've iced an Arrow at 10K once (no there wasn't SUPPOSED to be ice there, buuuuut...) Needless to say I got out of it but, that was enough. If there is even a remote chance of ice, I'm driving. I have no problem flying up and down the Valley at 6K in solid IMC, but 12K over a pass? No.
 
GCA319 said:
Most people who die in icing realted crashes have experienced icing before the day they crashed...Moral to the story, don't launch a 172 into known icing and if you encounter it-get the hell out of it.
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....b....b....bu.....bu.....but nothing ever happened before(!)!
 
I have picked up ice several times on my 172. The worst was clear ice about 1/4-3/8" thick. The plane was at max gross weight and flew like a pig with the ice on it. The stall warning was going off in level flight and full power. To keep it flying I had to put it into a shallow decent. I started losing power (I think this was from ice on the prop) and I was glad when I broke out of the clouds. After about 5 mins in the sun the ice started to break off the leading edges of the wing and some of it hit the tail sounding like some one was hitting the tail with a hammer.

BTW I picked up all the ice in just a few mins.

My suggestion is to avoid all icing conditions.
 
It's bloody stupid as well as illegal to intentionally fly a C-172 into conditions where you know you will pick up ice.
 
I've been iced up once due to unforecast ice fog and don't ever want to do it again. I also taught sim for a number of years and don't think the training is as dramatic (scary) as the real thing.

Dave Krall CFII said:
I would strongly advise against flying ANY non-K aircraft in known ice because it is both very dangerous and against FARs.

Go to a simulator and safely see how you handle things while VMC in a simulated ice build-up for your selected aircraft.
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When the situation arises where you are contemplating a go/no go decision (in an aircraft not approved for flight into known icing) based on forecast icing or if temps will be at and below 5 deg C at altitude in visible moisture the answer should probably be... no.
 
Ugh. NEVER on purpose. It's gonna be different every time. There's nothing to be gained from icing up on purpose. I'm glad I had a CFII with me the first time, but going into ice on purpose does nothing but take a few beats off the ol' ticker.

If you fly IMC in the Midwest in the winter, you're gonna get inadvertent icing sooner or later (always have outs). I fly a lot, and I've gotten ice several times, which is several more than I'd have liked. You really never know - I've climbed through a layer with no ice at all, and maybe 20 minutes later descended through the same layer and picked ice up.

That said, there are better and worse situations. If I'm in ice, there's several helpful factors I'd like to have on my side:

Airplane:
1) More horsepower > less horsepower.
2) Fat, high-lift wing is better than a skinny, high-speed wing.

Operational factors:
3) Lighter is better than heavier
4) Do not cruise in IMC
5) Stay high as long as possible, take a slam-dunk and avoid descending into and staying in a layer for a long time. (Last time I did this, they asked if I needed some vectors or something to get down in time... No sirree, I did my power reductions and slowed down up high so I could just drop through the IMC - worked beautifully, but there was no ice anyway.)

Other weather factors:
6) Good visibility and high ceilings - We want the approach to pretty much be a known "make". I don't want to have to miss an approach with potential ice.
7) Best is if it's high enough to get the visual, but if it's necessary to shoot an approach, it's best to have above-freezing air above the IAF and FAF so that there won't be significant time spent at sitting in ice on the way in on the approach.

There's worse birds than a 172 - The SR20 comes to mind - But it sure wouldn't be my first choice to get into an inadvertent icing situation, MUCH less going into it on purpose. :frown2:
 
Do people have accidents in icing because they got into icing or because they didn't take the outs?

(bit of a rhetorical question)


If you fly IMC you will get into icing sooner or later, its what you do about it.
 
You can assume that the mental giants who blithely advocate "always have outs" are those who have never been trapped by unforecast icing and have no clue about what really happens when you find yourself in such a situation.

In my case the plane wouldn't climb, would maintain only 120 IAS rather than the normal 150 at full power, and proved to have stall speed of ~100 KIAS (no flaps) when I pulled the power about 3' above the runway after an ILS to mins. I have been scared before and after that particular incident but nothing else even close. If the other airport with an ILS and 400' lower elevation hadn't been available within 20 miles away, the happy ending and cab ride home might have been different.

Within a month I owned a FIKI model of the same plane.



Alexb2000 said:
Do people have accidents in icing because they got into icing or because they didn't take the outs?

(bit of a rhetorical question)


If you fly IMC you will get into icing sooner or later, its what you do about it.
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wabower said:
I've been iced up once due to unforecast ice fog and don't ever want to do it again. I also taught sim for a number of years and don't think the training is as dramatic (scary) as the real thing.
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I'm positive simulator training for non-K aircraft and pilot performance in icing conditions are not as scary as actually flying in known ice.

....studies have shown this is because of the very low death rate in simulated ice v. non-K flight in actual icing....
 
Darwin Award candidate. Icing conditions are too unpredictable and are not repeatable. The absolute worst reason for doing something is because an instructor did it...instructors are perfectly capable of being stupid.

Bob Gardner
 
Just from glancing at these posts:

1. It seems most IFR pilots have gotten into some ice in a non-FIKI aircraft at one time or another.

2. No one intended to get into icing, but that didn't stop it from happening.

3. It was a scary experience for many, one most were not trained to deal with.

If all that is true it might not be a crazy notion for a CFI to show someone a little ice in conditions where you can easily get out of it. I am NOT advocating that, only suggesting that there might be an argument to give students a little experience in icing (especially in certain parts of the country). Even just to show how serious it is so they don't act cavalier about it. The alternative is what the other 99.999% of us do; which is figure it out on our own when we encounter it.:dunno:
 
My IR training was during the winter and spring months in the KC area. We found many days to climb or descend through a shallow layer that would provide a couple minutes exposure to rime. If the training had taken place a few months later the closest ice would probably have been in Siberia.

Alexb2000 said:
Just from glancing at these posts:

1. It seems most IFR pilots have gotten into some ice in a non-FIKI aircraft at one time or another.

2. No one intended to get into icing, but that didn't stop it from happening.

3. It was a scary experience for many, one most were not trained to deal with.

If all that is true it might not be a crazy notion for a CFI to show someone a little ice in conditions where you can easily get out of it. I am NOT advocating that, only suggesting that there might be an argument to give students a little experience in icing (especially in certain parts of the country). Even just to show how serious it is so they don't act cavalier about it. The alternative is what the other 99.999% of us do; which is figure it out on our own when we encounter it.:dunno:
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Alexb2000 said:
it might not be a crazy notion for a CFI to show someone a little ice in conditions where you can easily get out of it.
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But it would still be illegal in an airplane not certificated for flight into known icing.

If you want to show that off, get the correct airplane.
 
wabower said:
My IR training was during the winter and spring months in the KC area. We found many days to climb or descend through a shallow layer that would provide a couple minutes exposure to rime. If the training had taken place a few months later the closest ice would probably have been in Siberia.
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I could see that as being beneficial. You got to see what rime looks like, how it forms, etc. Without having to find out later in the real deal.
 
bflynn said:
But it would still be illegal in an airplane not certificated for flight into known icing.

If you want to show that off, get the correct airplane.
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Agreed. I just don't know how many schools have a FIKI aircraft, few I would think. So, in most cases it comes down to a choice by the CFI: show them something, or don't and hope they figure it out.
 
I actually do teach weather management in winter. Of course, it is done in a FIKI ship.
 
No, no, no,

But if caught in the mentioned scenario then consider a nonprecision approach and dive through the ice.
 
Some years ago I got caught in rapidly accumulating ice (absolutely unforecast) in a 160hp 172 on an extended ILS approach. Airspeed decreasing and unable to maintain assigned altitude. Landed but with a bunch of ice on every surface. Had a very experienced CFI in the right seat. Scared both of us. I can't imagine doing it on purpose.
 
Garthur said:
I have picked up ice several times on my 172. The worst was clear ice about 1/4-3/8" thick. The plane was at max gross weight and flew like a pig with the ice on it. The stall warning was going off in level flight and full power. To keep it flying I had to put it into a shallow decent. I started losing power (I think this was from ice on the prop) and I was glad when I broke out of the clouds. After about 5 mins in the sun the ice started to break off the leading edges of the wing and some of it hit the tail sounding like some one was hitting the tail with a hammer.

BTW I picked up all the ice in just a few mins.

My suggestion is to avoid all icing conditions.
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Was your carb heat or alternate air (if injected) on?

The air filter is in a great place for accumulating ice
 
Alexb2000 said:
If all that is true it might not be a crazy notion for a CFI to show someone a little ice in conditions where you can easily get out of it. I am NOT advocating that, only suggesting that there might be an argument to give students a little experience in icing (especially in certain parts of the country). Even just to show how serious it is so they don't act cavalier about it. The alternative is what the other 99.999% of us do; which is figure it out on our own when we encounter it.:dunno:
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Every time I've gotten into icing, I knew it might happen. While I hear a number of stories regarding saying there was unforecast icing, it basically comes down to:

1) Are you in a cloud?
2) Is it below freezing?

Now we are aware that, depending on the weather, there's more to it than that. But really, the majority of folks who tell me they got into inadvertent icing knew that they were entering a cloud with temps below freezing. Since I spent a large amount of my flight time in parts of the country where 90% of the time cloud = ice, I'm particularly wary of it.

Now, one could argue the logic of exposure. Doing so in an appropriately equipped plane with an experienced icing pilot does make more sense. But to willfully encounter icing in a plane not equipped to deal with it for the perceived instructional benefit seems much like the old practice of killing an engine on a twin right after the gear comes up - it killed too many students and instructors, and was eliminated for a reason.
 
Just wondering. If you are flying IFR and then start to pick up ice. At that moment, does it become flight into known ice? In other words, if you don't take action to get out of the cloud, is it against the FARs to continue?
 
AuntPeggy said:
Just wondering. If you are flying IFR and then start to pick up ice. At that moment, does it become flight into known ice? In other words, if you don't take action to get out of the cloud, is it against the FARs to continue?
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Frankly, at that point the FARs don't matter. Get the hell out!
 
Alexb2000 said:
Agreed. I just don't know how many schools have a FIKI aircraft, few I would think. So, in most cases it comes down to a choice by the CFI: show them something, or don't and hope they figure it out.
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I've seen some - Where I learned to fly there's a FIKI Seneca for rent, and there's a FIKI TwinStar or two at UGN last I checked... But I don't think I've ever seen a FIKI single for rent. FIKI SR22/Mooney/T210 could conceivably be on the line somewhere, but definitely rare.
 
Alexb2000 said:
I could see that as being beneficial. You got to see what rime looks like, how it forms, etc. Without having to find out later in the real deal.
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The problem with that kind of thinking is that it leads the experimenter to believe that, given a set of circumstances, certain ice types and shapes will form. Bad idea. A cloud that delivers a light coat of rime one day might deliver an inch in 30 seconds the next day. Every flight into known icing conditions is "the real deal," and you have no way of knowing what to expect on a given day.

I've flown in a lot of ice (in FIKI airplanes), and I just can't understand the idea of going into icing conditions with a non-FIKI plane on purpose. The "How does it handle ice?" question might be answered by an uncontrolled descent into terrain.

Bob Gardner
 
AuntPeggy said:
Just wondering. If you are flying IFR and then start to pick up ice. At that moment, does it become flight into known ice? In other words, if you don't take action to get out of the cloud, is it against the FARs to continue?
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The most recent interp from the General Counsel leaves it pretty much up to the pilot. IF you get into trouble and IF you need assistance, they are going to come down hard on you. The new standard is "Would a prudent pilot, knowing what you know, make this flight?" Lot of prudent pilots in this thread.

The old standard, whereby getting any ice at all was a violation, is no longer valid. By ANY standard, with a non-FIKI you are expected to take immediate action to get out of the icing conditions. It violates common sense to continue.

If you look at Appendix C to Part 25 (Part 23 is included by reference), to see just how limited FIKI certification is, you will see that the maximum droplet size contemplated is 40 microns...smaller than a human hair...so if you can see the droplets you are in conditions beyond which FIKI applies; if I recall the distance correctly, if the cloud you are in is stratus and extends more than 17 miles, you are once again outside of FIKI standards. All FIKI certification buys you is time to escape, not permission to continue.

Bob Gardner
 
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Bob has it right. Once in icing, you need to get out - FIKI or not.

Now, what you do to get out of it? There are multiple options, and I'm not going to go into them here.
 
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