Icing conditions- What’s a real threat?

Jaybird180

Jaybird180

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Jaybird180
This past weekend, I had my pre-XC prog check with a Senior CFI. During the flight, I could see a haze in our flight path at our altitude. I asked if it’s a concern for icing and the CFI confidently said “no”. I held my course.

It got me thinking. The CFI has enough experience to know it wasn’t a threat. How am I to develop this judgment? I know from books that visible moisture with temps below 0-deg-C represents known icing conditions and I considered this to qualify. If I were solo, I would have chosen another path. I noted that as we got closer, the visibility through the haze improved. I don’t know why, but it did. Back on the ground, I asked him about this and I didn’t get anything educational from the response.

So, I ask here: How do I recognize the conditions ripe for icing (other than the obvious- stay out of the clouds advice)?
 
I guess you had to be there....

IMHO, haze does not constitute icing conditions in and of itself. Haze can be entirely dry, made up of gazillions of tiny pollution particles. Honest-to-goodness clouds are made up of water droplets, and the threat of icing is connected directly to droplet size. While I defer to Scott Dennstaedt's knowledge of specifics, you biggest concern should be vertical development...in a convective situation, droplets are rising, joining hands, and working together to pose a hazard. My guess is that your instructor saw no cloud on the horizon.

Bob Gardner
 
Jaybird180 said:
I noted that as we got closer, the visibility through the haze improved. I don’t know why, but it did. Back on the ground, I asked him about this and I didn’t get anything educational from the response.
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Think of it like approaching an asteroid field in space - when you are on the outside, you have the whole field of rocks in between you and the other side and they tend to blocl your view. As you pass through the field, you put more of those rocks behind you and therefore have less in front of you blocking your view.

When I was on my first x-country solo I had an interesting experience with haze - I was on the return leg and saw what I thought was a widespread overcast marine layer ahead of me. It was not forecasted. I became very concerned, obviously and did not want to get stuck on top and not be able to descend through the clouds to my destination. Funny thing was, the AWOS at both my destination and an airport 7 miles north of me reported 'clear skies'. BUT, I could SEE the clouds! So, I descended (had to get down to 750 - 1000' AGL and flew out over the shore) to get below the layer and arrived at my home airport safe and sound, but when I got out of the airplane, I looked around me to see clear blue skies!

I then realized what I had experienced and seen was a temperature inversion where the conditions were just right at that altitude for extreme haze. When viewed from the same altitude, it was thick enough that it sure looked like a cloud layer, but viewed from above or below, it was so thin that you could see right through it!

Not sure if that helps, but while haze is caused by moisture, it is not the same thing as clouds.
 
Fearless Tower said:
Not sure if that helps, but while haze is caused by moisture, it is not the same thing as clouds.
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I thought haze was caused by pollution and mist was caused by water. If you're flying VFR, you shouldn't have to be too concerned about ice because you're going to stay out of visible moisture, right?

Scott's web site and individual instruction is the best I know of for weather related pilot training.
 
That website goes beyond the scope of my question.

The ground temp was below freezing has been for several weeks. I can expect the tempertature while flying to be lower than whatever the ground temperature is. Cloud floors were 6k and falling during the day, so I know something was happening. This haze was near the shoreline of the Chesapeake bay, so I thought that it was possible to have visible moisture...I thought I was looking right at it!

What can I do short of peeking over the precipice of icing conditions (flying into icing in a FIKI aircraft) to truly know- and more importantly how to avoid icing?
 
PittsDriver said:
I thought haze was caused by pollution and mist was caused by water. If you're flying VFR, you shouldn't have to be too concerned about ice because you're going to stay out of visible moisture, right?
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As I recall, flying in New England in the summertime, it was almost always humidity based and reported in Metars and via ASOS/AWOS as Haze.

Typical summer VFR weather back there was '5 miles in Haze' and it was not pollution.
 
Jaybird180 said:
This haze was near the shoreline of the Chesapeake bay, so I thought that it was possible to have visible moisture...I thought I was looking right at it!
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Think of it more as clouds are concentrated moisture - when you see the haze it is alot more spread out.

Stay out of the clouds when the temps are down and you generally live to fly another day.
 
Fearless Tower said:
As I recall, flying in New England in the summertime, it was almost always humidity based and reported in Metars and via ASOS/AWOS as Haze.

Typical summer VFR weather back there was '5 miles in Haze' and it was not pollution.
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I don't doubt you that it was reported that way but if they meant reduced viz because of moisture in the air it would be incorrect. BR - mist - moisture in the air; HZ - haze - dry particulate in the air. If you go down in the Atlanta area, a good day there in the summer is 4 - 5 miles in mist and it's all humidity/moisture. Here in the Baltimore/Washington area, a bad day is 4 - 5 miles in haze and and sometimes it's 4 - 5 in mist.
 
If you're flying VFR airframe icing really shouldn't be much of a concern. However, if you encounter mist, which one can on days where the temps aloft are above freezing, you can certainly suffer carburetor icing. Mist is easily distinguishable from haze, and should show up on weather reports. That's where your carburetor heat comes in.

I haven't seen that much haze in the wintertime. Frequent precipitation usually washes all the particulates out of the air in these latitudes.
 
All of you experienced pilots got that way by...experiencing stuff (go figure)! How do I get it without doing anything dumb? I can see that many of you may take that experience for granted whereas a person like myself- this is all new to me.

Wht I'm trying to be able to do is distinguish based on what I see outside the cockpit and determine a real threat from a perceived threat. I'm not concerned about weather reports, etc.
 
Jaybird180 said:
All of you experienced pilots got that way by...experiencing stuff (go figure)! How do I get it without doing anything dumb? I can see that many of you may take that experience for granted whereas a person like myself- this is all new to me.

Wht I'm trying to be able to do is distinguish based on what I see outside the cockpit and determine a real threat from a perceived threat. I'm not concerned about weather reports, etc.
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Michael (Dr Oragami) is correct -- as a VFR pilot you shouldn't be in clouds, period.

No clouds, no airframe icing (except in some rare, unusual conditions).

Carb icing is a concern for VFR pilots flying most trainers -- make sure you understand how, why, and what to do.
 
Let me clarify- my training (IMHO) includes too little risk. Experiencing risk in measured amounts is what builds discernment and good judgement. I'm soon to be cut loose (legally) and don't think it's wise to do things just because I will have a certificate that says I can.
 
Jaybird180 said:
Let me clarify- my training (IMHO) includes too little risk. Experiencing risk in measured amounts is what builds discernment and good judgement. I'm soon to be cut loose (legally) and don't think it's wise to do things just because I will have a certificate that says I can.
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That's what the Private Pilot Certificate is for -- it's your license to learn.

:thumbsup:
 
Jaybird180 said:
That website goes beyond the scope of my question.
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It's a complicated subject - you're not going to get a simple answer - understand that material on that website and you'll be better off. There is no absolute answer in icing - understanding it is almost an art because there are so many factors at play.

Jaybird180 said:
The ground temp was below freezing has been for several weeks. I can expect the tempertature while flying to be lower than whatever the ground temperature is.
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False. Temperature inversions are fairly common. Never expect, know. What did your OAT gauge say?

The fact of that matter is that the "haze" or "mist" or whatever probably wasn't loaded with moisture and wasn't really a solid "cloud". It posed little risk and you likely had outs. Your instructor didn't see the point in avoiding it since it wasn't a cloud, you could maintain VFR, and you had a way to escape if you did pick up ice, which would occur at a very minimal rate.

dmmorackmak said:
No clouds, no airframe icing (except in some rare, unusual conditions).
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I've experienced it while VFR. Get a little freezing precip that is hard to see and you can take on ice while maintaining VFR.
 
Jaybird180 said:
How do I get it without doing anything dumb?
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You do exactly what you are doing here - asking questions and gaining from other's experience.

The only other way to get it is.....fly alot and establish personal minimums that you can expand as you gain more experience. When it comes to weather flying (as well as other aspects of flight), a pilot with thousands of hours is naturally going to be more comfortable flying in certain weather conditions that a student or newly minted private pilot would not.
 
Jaybird180 said:
Let me clarify- my training (IMHO) includes too little risk. Experiencing risk in measured amounts is what builds discernment and good judgement. I'm soon to be cut loose (legally) and don't think it's wise to do things just because I will have a certificate that says I can.
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It is perfectly acceptable to be chicken.

I ran into some light rain on a trip shortly after I became current again, and ended up doing a 180 because it exceeded my comfort level.

Push the boundaries a little at a time, and get expert support if you need it.

I agree with Dan. You are given a license to learn, and you have not been prepared for every possible scenario. Be conservative and be open to learning opportunities.
 
bobmrg said:
While I defer to Scott Dennstaedt's knowledge of specifics, you biggest concern should be vertical development...
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My intuition suggested this during the years when I was making IFR flights to the Portland and Seattle areas. I always figured that the coastal airways were less likely to give me icing problems, because of the reduced opportunity for orographic lifting.

It also appeared to me that the beach hardly ever gets down to freezing temps, so I figured my outs were better there too.
 
Jaybird180 said:
All of you experienced pilots got that way by...experiencing stuff (go figure)! How do I get it without doing anything dumb? I can see that many of you may take that experience for granted whereas a person like myself- this is all new to me.
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As John and Martha King like to say, "Good judgment comes from experience; experience comes from bad judgment!" :wink2:
 
Jaybird180 said:
I'm soon to be cut loose (legally) and don't think it's wise to do things just because I will have a certificate that says I can.
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A wise attitude.

The day I got my instrument rating, I became very keenly aware of that fact!
 
In truth, I don't know how common it is. I do know that when it came time for me to fly home from Seattle, the reports of freezing rain at Boeing Field made the no-go decision very easy!
 
scottd said:
It depends on where you fly. If you fly in the area from Charlottesville, Virginia to Charlotte, North Carolina, it's quite common as seen on the map below.

Classical-SLD-Events.gif
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Scott -- is that days of freezing rain per year/ At ground level?
 
scottd said:
Steve,

Thanks for the plug. It's now located here.
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sorry about that, the previous was an old Favorite/Bookmark i had

fwiw, i've run into vfr freezing rain more than once, looks like virga, only lower, in tx and other points south in the wintertime

always light enough to be able to see through to the horizon on the other side and only a trace of build up that "sublimated" soon after i left the shaft
 
Haze won't give you ice.

Jaybird180 said:
This past weekend, I had my pre-XC prog check with a Senior CFI. During the flight, I could see a haze in our flight path at our altitude. I asked if it’s a concern for icing and the CFI confidently said “no”. I held my course.

It got me thinking. The CFI has enough experience to know it wasn’t a threat. How am I to develop this judgment? I know from books that visible moisture with temps below 0-deg-C represents known icing conditions and I considered this to qualify. If I were solo, I would have chosen another path. I noted that as we got closer, the visibility through the haze improved. I don’t know why, but it did. Back on the ground, I asked him about this and I didn’t get anything educational from the response.

So, I ask here: How do I recognize the conditions ripe for icing (other than the obvious- stay out of the clouds advice)?
Click to expand...
 
Jaybird180 said:
All of you experienced pilots got that way by...experiencing stuff (go figure)! How do I get it without doing anything dumb? I can see that many of you may take that experience for granted whereas a person like myself- this is all new to me.

Wht I'm trying to be able to do is distinguish based on what I see outside the cockpit and determine a real threat from a perceived threat. I'm not concerned about weather reports, etc.
Click to expand...


???? What makes you think that any of us managed to avoid doing anything dumb, or that it is even possible? You'll never avoid doing every dumb thing, the key to surviving is recognizing it was dumb as soon as you can, figuring out what to do without making things worse, and when it all goes to hell understanding your aircraft well enough to keep it under control, minimize the energy for impact and try minimize the rate of decelleration in the crash and fly as far into the crash as possible. It ain't over till you've come to a stop so never give up.
 
COFlyBoy said:
It is perfectly acceptable to be chicken.

I ran into some light rain on a trip shortly after I became current again, and ended up doing a 180 because it exceeded my comfort level.

Push the boundaries a little at a time, and get expert support if you need it.

I agree with Dan. You are given a license to learn, and you have not been prepared for every possible scenario. Be conservative and be open to learning opportunities.
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Very good advice.

And later on when you're more comfortable, you'll appreciate finding light precipitation when VFR on a nice day, because it'll mean less scrubbing of the airplane during the next airplane wash day.

120-knot water does a great job of getting the grime off of everything. If you can't find enough of it though, it'll streak the dead bugs from the flight all over the windscreen and make visibility awful for a whole new reason. ;)
 
Forecast for my upcoming XC is 41F and rainy. Just the reason to ask these questions, I need to know what's real.
 
jesse said:
I've experienced it while VFR. Get a little freezing precip that is hard to see and you can take on ice while maintaining VFR.
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Yup. I iced up a Super Cub VFR - It was some sort of small-droplet freezing virga that wasn't really visible in flight, except for the windscreen getting a bit harder to see through:

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Henning said:
???? What makes you think that any of us managed to avoid doing anything dumb, or that it is even possible? You'll never avoid doing every dumb thing, the key to surviving is recognizing it was dumb as soon as you can, figuring out what to do without making things worse, and when it all goes to hell understanding your aircraft well enough to keep it under control, minimize the energy for impact and try minimize the rate of decelleration in the crash and fly as far into the crash as possible. It ain't over till you've come to a stop so never give up.
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EXCELLENT advice. And you can make dumb mistakes that don't involve crashing, too. I've never crashed, but I've sure made my share of dumb mistakes - Everyone has. The trick is to learn from them, and to make sure that even when you DO make a mistake, you have some built-in safety margins to allow yourself to get out of the situation.

I've said it many times before, I'll say it again: To become a better, pilot, you must push the envelope - But only push it one corner at a time. :yes:

dmccormack said:
Another piece of advice -- don't make flying plans based on any forecast more than 2 days out.
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Amen. I never cancel a flight until the day of unless some other factor demands an earlier decision. If I made my no-go decisions even one day earlier, I estimate that I would cancel 5 times as many flights as I do. Generally, I've had very good luck using GA as transportation by waiting to see what the actual conditions are.
 

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flyingcheesehead said:
Amen. I never cancel a flight until the day of unless some other factor demands an earlier decision. If I made my no-go decisions even one day earlier, I estimate that I would cancel 5 times as many flights as I do. Generally, I've had very good luck using GA as transportation by waiting to see what the actual conditions are.
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I would add... "And by being willing to change the plan." Going four hours earlier or later often makes all the difference, and/or being willing to go 100 miles or more out of your way...

My wife and I got some pretty decent Chinese food at a restaurant airport in West Texas once, trying to go around a 150 mile long line of thunderstorms that were moving East between Denver and Houston. Same trip, coming back, we ran into forecast-to-be-gone-already lowering ceilings and had to hole up at a public (but deserted on weekends) paved crop-duster strip for a few hours, reading magazines and a book, somewhere near College Station.

You gotta be the type that can handle a little detour... if you're so Type A that you "must" go and be there at a particular time, pay the airlines. (And even they won't always get you there.) You'll also probably end up an accident statistic.

Pack a small cooler with sandwiches and water/sodas, toss it in the back, and head out for an adventure if the weather is "flyable, but there's some "stuff" between here and there" and choose the route to avoid the nasty stuff... land if it gets bad, and generally, you can have quite a lot of fun on a little adventure like that. Especially if you like meeting new people. Learn to read the weather... even if it means taking or auditing a local meteorology course, or spending some time in self-study.

We got into Hooks airport in Houston exactly one minute after the tower closed that night... I know because the controller said he'd wait to clear me to land and joked that he didn't get paid for that extra minute. Sure was nice of him to stick around after I asked him to turn the lights up so we could spot the airport. :) As the wheels touched the pavement, the announcement started, "Attention all aircraft, Hooks Tower is now closed. The common traffic advisory frequency is..."
 
denverpilot said:
We got into Hooks airport in Houston exactly one minute after the tower closed that night... I know because the controller said he'd wait to clear me to land and joked that he didn't get paid for that extra minute. Sure was nice of him to stick around after I asked him to turn the lights up so we could spot the airport. :) As the wheels touched the pavement, the announcement started, "Attention all aircraft, Hooks Tower is now closed. The common traffic advisory frequency is..."
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I've had that announcement at KOLM while in the pattern. 8 PM local rolls around and they close up shop. But they will leave the lights on for you. :D
 
denverpilot said:
I would add... "And by being willing to change the plan." Going four hours earlier or later often makes all the difference, and/or being willing to go 100 miles or more out of your way...
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And remember that "100 miles out of your way" doesn't mean 100 extra miles of flying. If you are on a 500nm leg and you bend it 100nm off course in the middle, you only add about 20nm to the trip. If you're flexible as to what your stops will be on a longer trip, it's quite easy to go way "out of your way" in between the departure and destination airports and not add much time to the trip at all.

Flexibility is the name of the game - The more flexible you can be in timing, routing, etc. the easier it is to make it to your destination.
 
Three ways to determine an icing threat, first is obvious..visible moisture and below freezing, this means there COULD be ice but does not mean that there WILL be ice. Second is PIREPS...check em before you go and see what other pilots have encountered around your area. Third is experience, if you experience ice you know where it is most likely to form and when it does form, just how fast it can and what the threat is.

Haze usually doesn't have anything to do with ice, it is usually just pollutants in the air, and even if it is moisture, it is not enough to cause ice on the airplane.
 
bzubrod said:
Three ways to determine an icing threat, first is obvious..visible moisture and below freezing, this means there COULD be ice but does not mean that there WILL be ice. Second is PIREPS...check em before you go and see what other pilots have encountered around your area. Third is experience, if you experience ice you know where it is most likely to form and when it does form, just how fast it can and what the threat is.
.
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1- I will remember that
2- I'm sure the pilot who made the PIREP didn't think there would be ice
3- Experience is a poor teacher; there are no retakes for flunking
 
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