Why no ice?

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Mtns2Skies

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Mtns2Skies
I was flying right seat with a buddy with his instrument. We flew from BJC (Denver Area) to BFF(Scottsbluff) for some food in a 182RG with a STOL kit. Visibility was maybe 1/2 miles to maybe a mile of vis for about .8 of the trip and the OAT was about 23F. Why the heck didn't we pick up ice?
 
Not enough moisture in the air you where flying in.
 
I would say that any visible moisture might have already been frozen which would've made it too cold to stick onto the airframe, but 23F or -5C most likely wouldn't do it. Under the conditions you described it seems as though icing would be likely. Interested to hear others' opinions on this.
 
Ryanb said:
I would say that any visible moisture might have already been frozen which would've made it too cold to stick onto the airframe, but 23F or -5C most likely wouldn't do it. Under the conditions you described it seems as though icing would be likely. Interested to hear others' opinions on this.
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The moisture was glaciated and had warmed to 23. This is a large arctic air mass...

Also remember that air warms coming down off the Rockies
 
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Clark1961 said:
The moisture was glaciated and had warmed to 23. This is a large arctic air mass...

Also remember that air warms coming down off the Rockies
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I'm not familiar with the area nor the current conditions. I was just basing that off of the OAT alone. Typically getting into -30 range, give or take, freezes any moisture in the air, reducing the the chances for anything to stick.
 
In my experience you pick up icing less than 50% of the times you might expect it, sometimes much less. Airframe icing forms when you have "supercooled" water droplets that hit your airframe. That means those droplets must be: a) below zero degrees C; and b) still liquid!
You might wonder how water can remain liquid below the freezing temperature, but that's actually very normal. Sufficiently cold water only freezes when it has something that shakes it a bit, and hitting your airplane does just that, at which point the droplet instantly freezes and adheres to the surface that shook it.
Having those supercooled water droplets hang around waiting for you to pass through is not all that common. Very often they are already frozen by the time you get there, so no (d)ice. (Already frozen ice/snow particles will bounce right off.)
Once you understand all this, you'd be much better equipped to fly safely through areas that are theoretically conducive to icing, and get your backside safely out of icing conditions when inadvertently encountered.
 
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I remember this one time being vectored to an Austin airport through hard IMC. The outside air temperature was around 0C. I was flying a 182. The controller was working another 182 at the same altitude that was reporting ice. I had nothing which I reported.
 
So how was the food and service at Scottsbluff? The airport restaurant seems to go through operators frequently. It's a nice facility but traffic might be too low to support it.
 
l8evator said:
So how was the food and service at Scottsbluff? The airport restaurant seems to go through operators frequently. It's a nice facility but traffic might be too low to support it.
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Fantastic service, food though looked promising was a bit disappointing overall. My fried chicken was undercooked and my buddy's burger was dry. But it was still a cool place.
 
Let'sgoflying! said:
Does a skew-T help with this question?
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Absolutely. It's my number one defensive weapon, coupled with this tool, which is very likely based on skew-T data. You generally want to avoid the areas of expected icing (esp. in non-FIKI), which skew-T does a good job of predicting. As far as the age of the droplets (old cold droplets tend to freeze and become less of a hazard), you can only guess, but logically the colder the droplets the sooner they freeze.
 
Ryanb said:
I'm not familiar with the area nor the current conditions. I was just basing that off of the OAT alone. Typically getting into -30 range, give or take, freezes any moisture in the air, reducing the the chances for anything to stick.
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That's really the thing about ice, you have to know the airmass and what it's been through.
 
Luckily nothing stuck. Flying into icing conditions in a non FIKI plane is not my idea of fun.
 
Ryanb said:
I would say that any visible moisture might have already been frozen which would've made it too cold to stick onto the airframe, but 23F or -5C most likely wouldn't do it. Under the conditions you described it seems as though icing would be likely. Interested to hear others' opinions on this.
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Likely because the moisture you saw was already frozen. And thus didn't stick to the frame of the airplane. It's definitely interesting though, under the conditions described, it seems like icing would be nearly unavoidable. I'm sure someone will break it down more, and give a more detailed if not better all a
 
Jim Case said:
Likely because the moisture you saw was already frozen. And thus didn't stick to the frame of the airplane. It's definitely interesting though, under the conditions described, it seems like icing would be nearly unavoidable. I'm sure someone will break it down more, and give a more detailed if not better all a
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The only way "icing would be nearly unavoidable" is if you had supercooled liquid water droplets sitting around and waiting for you. In many situations they are either already frozen, or not cold enough.
The OP's 23F OAT (-5C) is certainly in the "danger zone", but the droplets encountered could have already been frozen when the aircraft met them, at which point they'd bounce right off.
As I mentioned above, in my experience very often the droplets you meet are frozen, so there is no icing, therefore this case wouldn't be at all surprising.
It's also possible the droplets were liquid but very small, which would have required a very long time to get an appreciable buildup.
 
Ryanb said:
I would say that any visible moisture might have already been frozen which would've made it too cold to stick onto the airframe, but 23F or -5C most likely wouldn't do it. Under the conditions you described it seems as though icing would be likely. Interested to hear others' opinions on this.
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Jim Case said:
Likely because the moisture you saw was already frozen. And thus didn't stick to the frame of the airplane. It's definitely interesting though, under the conditions described, it seems like icing would be nearly unavoidable. I'm sure someone will break it down more, and give a more detailed if not better all a
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Jim,
What you wrote above is nearly the exact same as what I said, almost word for word too, you just re-stated it. Did you really just come up with the same idea that I had?! :dunno:
 
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It's pretty tough to get any light airplane actual IMC in the Denver area. On the rare occasions when they get that kind of weather it can quickly exceed the abilities of most GA aircraft.
 
I've been IMC @ 0*c in a few types. No ice. It happens.
 
tlglenn said:
I remember this one time being vectored to an Austin airport through hard IMC. The outside air temperature was around 0C. I was flying a 182. The controller was working another 182 at the same altitude that was reporting ice. I had nothing which I reported.
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Ice can be strange. Just the other day I was getting vectored for an approach and while I was east of town there was no ice, but north and west of town I started to pick up some light ice. I was in IMC the whole time, and there was a guy who just gave a pilot report of negative ice right before I showed up in the same area he was at when he reported. So in your situation, it is conceivable that at his location there was ice but not in your location.

jordane93 said:
Luckily nothing stuck. Flying into icing conditions in a non FIKI plane is not my idea of fun.
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The conditions may have been conducive to ice, but the OP never mentioned anything of flying in known ice conditions. It might be a minor nit to pick but there is a difference. ;)
 
Ryanb said:
Jim,
What you wrote above is nearly the exact same as what I said, almost word for word too, you just re-stated it. Did you really just come up with the same idea that I had?! :dunno:
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Seems like it. Any other explanation as to why that would happen?
 
RotorDude said:
The only way "icing would be nearly unavoidable" is if you had supercooled liquid water droplets sitting around and waiting for you. In many situations they are either already frozen, or not cold enough.
The OP's 23F OAT (-5C) is certainly in the "danger zone", but the droplets encountered could have already been frozen when the aircraft met them, at which point they'd bounce right off.
As I mentioned above, in my experience very often the droplets you meet are frozen, so there is no icing, therefore this case wouldn't be at all surprising.
It's also possible the droplets were liquid but very small, which would have required a very long time to get an appreciable buildup.
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This is what I meant by a "more detailed explanation" . I was simply referring to icing being highly likely in this senerio.
 
So the airframe is below freezing and the air hitting it is below freezing - and the moisture is below freezing- its gonna stick how?

I've usually only seen ice in convective clouds [cumulus] in the top 1000 feet or so - and then again in freezing rain in a layer in the clear - which makes a helluva lot of sense.
 
Ryanb said:
I find that hard to believe Jim. Now I feel like you're just trolling. o_O
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I could care less what you believe. I don't know what trolling is but believe me, I don't really have enough spare time to waste arguing with you, you are going on the ignore list.
 
Fearless Tower said:
That's the ONLY place you've seen ice? Really???
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other than thats not what I said -

on an airplane in the air . . . . sure

I've seen ice in my drink, I've put in a margarita machine, I see it on the mountains - but I never see it on the ground anymore . . .
 
comanchepilot said:
other than thats not what I said -

on an airplane in the air . . . . sure

I've seen ice in my drink, I've put in a margarita machine, I see it on the mountains - but I never see it on the ground anymore . . .
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Me thinks you must not have spent much time in the clouds in cold weather then. I've picked up ice in many non convective cloud layers.
 
Fearless Tower said:
Me thinks you must not have spent much time in the clouds in cold weather then. I've picked up ice in many non convective cloud layers.
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c.mon - what I said was the "I've usually only seen ice. . . . ' I never said only or never- words mean things. All of them.

You're running into ice alot in non-convective winter stratus - maybe launching into those conditions in a non-FIKI airplane requires a different decision tree. . .
 
comanchepilot said:
c.mon - what I said was the "I usually only seen ice. . . . ' I never said only or never- words mean things. All of them
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Still it's an odd thing to say 'usually' about.

At any rate, maybe I misinterpreted your original post, but it seemed you were implying that as long as you were busting around in stratus laters, you'd be fine, which is contrary to my ice experience.
 
Mtns2Skies said:
Fantastic service, food though looked promising was a bit disappointing overall. My fried chicken was undercooked and my buddy's burger was dry. But it was still a cool place.
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I think that's the first time I've ever heard "cool" and "Scottsbluff" in the same sentence. :)

Clark1961 said:
That's really the thing about ice, you have to know the airmass and what it's been through.
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Sometimes air masses come with all sorts of emotional baggage. ;)
 
Does a skew-T help with this question?
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Absolutely.
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Lets see it then, for the place and time in the o.p. Someone show us why or how he could have known in advance.
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I did not see anyone post this (the plot for the time and place in question and a description of how it works). Starting to doubt that it can predict as described. Surely plot history is available?
 
Its the same as in your car. Some snowstorms, sleet storms and rainstorms produce ice and some don't. The odd thing about icing to remember is you CAN get ice when the temperature is ABOVE 32 degrees, maybe as high as 38 degrees F or even higher. This is due to the existence of water that is below 32 degrees but hasnt turned to ice. This water floats around in the air, and the air it is in can be at a higher temp than freezing, which seems kind of odd. When the airplane collides with the water it turns into ice. This phenomenon is called "supercooled droplets of water". Most of us learned that when water goes below 32F it turns to ice. Turns out it CAN stay liquid down to quite a bit below 32F. Interesting phenomenon. When an airplane runs into an area of supercooled drops of water, the leading edges of the airplane and the windshield all get covered with ice. Not nice.

There are two kinds of ice. Clear ice and rime. Clear ice is not always perfectly clear, it can be white. It is white from air trapped inside the ice. Clear ice can be smooth or knarly surfaced. There is also "mixed ice", which is a combination of clear and rime. Rime is more like frost. If you get ice and report it to ATC they will want to know the outside temperature and the type of ice.
 
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