Interesting experience yesterday

[Paul Folbrecht]

Did a short trip yesterday from MWC to OSH with the gf, just to go,
about 3PM. Was planning on cruising at 3 to avoid ice in the clouds,
which were not far about that at all. Briefer tells me there's an
inversion aloft, and the freezing level is at NINER. Cool, great!
Filed for 4, planning on getting actual the whole way there. On the
climb, notice the temp dropping slowly the whole way. Inversion? Where
is it? Into solid IMC around 32-3300, as expected. Temp is around 30
now. At 3800, it's a little less, about 28. I thought, what am I
doing? I'd promised myself, recently, to stay out of the clouds below
freezing (even though I've done it a number of times and never picked up
ice I couldn't deal with by getting lower, out of the clouds or >0.). I
called approach and asked for and got 3. Back to near VFR - very hazy,
very poor vis, but not in cloud.

So, what was up? The forecast was wrong, it seems. There was
definitely *a* freezing level way below 9. May have been an inversion
ABOVE that, and another FL at 9, but what the heck good does that do me?
The briefer outright ENCOURAGED me to fly in the clouds - in fact he
encouraged me to get on top and give him a pirep (tops around 5-6). (Of
course I know that matters for nothing but it makes you think!)

Thoughts about that?

This got me to thinking once again about IFR and icing conditions (this
topic hasn't ever been discused in this NG, has it? cough cough). As I
said, my new rule - which is the smart way to do things - is to just
stay out of the clouds below freezing in my very non-known-icing
certified 152. I formerly took the more common position that I'll fly
in cloud as long as there's an out - if I know going lower will get me
out of icing and keep me above MEA. Then, a few weeks ago, I ended up
coming into MWC from JVL with what was supposed to be 3000'+ ft cigs.
Weather (snow) came in early - just a bit early, 1/2 hour, to be fair -
and I ended up in actual almost all the way with no where to go (no ice,
luckily) and doing the VOR 4 with 1600' and 1.

Thinking about the whole thing later on unnerved me as I realized just
how screwed I'd have been if I'd started getting ice enroute. Temps
were right in the zone, around 25-27. There was no way the cigs were
above the MVA (I was direct) or the OROCA for that matter - what to do?
Tops were way up there. Declare and descend to 1000-1500' agl? I
probably would not have been prosecuted, as WX was not forecast, but no
fun would that be in any case!

Thoughts on all this? Other than the obvious?

How I wish we could have a much better idea of where that ice is gonna be.

~Paul
~PP-SEL-IA

[Peter R.]

Paul Folbrecht > wrote:

> Thoughts on all this? Other than the obvious?

Really, you have three options: Park your airplane until April, Only fly
on VFR days, or develop a plan that you will only fly in IMC on those days
where you have an out. Don't forget that doing a 180 and returning is one
form of an out, if needed.

> How I wish we could have a much better idea of where that ice is gonna be.

Have you tried the icing predictions at ADDs?

http://adds.aviationweather.noaa.gov/icing/

(click the radio button to correspond to your time in the clouds, then the
altitude level on the left to see the icing predictions. A bit more
detailed than the generalized airmet Zulu.)

Also, from what I have read in the latest issue of IFR Magazine, early 2006
there will be a much more detailed icing forecast to replace the
broad-brushed airmet Zulu. This will certainly be helpful in your case.


--
Peter

[Jim Burns]

The same "inversion" was predicted Christmas Eve. I checked the forecast
about 20 times the day before thinking that maybe we'd fly over to the
in-laws in MI Christmas Eve and then back home Christmas Day, just like we
did last year. Tops were forecast to be up to FL20, surface vis sucked,
about 1/2 mile in fog, ADDs showed a high chance of icing around 3000, less
at 6000 in warmer temps, no prediction at 9000 and even warmer temps.

My decision was to stay on the ground. I wasn't going to depend on the
forecast of an inversion.

The low vis with a freezing layer close to the ground just took away my most
important out, the one of a high probability of successfully shooting an
approach without picking up ice. If I was to shoot an approach, start
picking up ice, then have to go missed due to either lack of vis or an iced
over windshield, I'd probably pick up more ice on my way back up AND the
hold is published at the same altitude as the highest icing prediction. My
only hope would be if the inversion was true and it actually was warmer up
above. Nah... I'll pass. Too many things would have to be perfect in order
to make the trip. Not saying it wouldn't have been possible, but I sure as
heck couldn't think of a reason that I'd want to take that many chances.

The next morning I watched two Freight Dogs on flightaware.com come back to
STE/CWA from MKE. Both had to hold for 45 minutes, one at 4000, one at
8000, until the tower over ruled the ASOS vis report of 1/4 and declared vis
of 1/2 so they could begin the approach. I was glad I was on the ground.


Jim

"Peter R." > wrote in message
...
> Paul Folbrecht > wrote:
>
> > Thoughts on all this? Other than the obvious?
>
> Really, you have three options: Park your airplane until April, Only fly
> on VFR days, or develop a plan that you will only fly in IMC on those days
> where you have an out. Don't forget that doing a 180 and returning is one
> form of an out, if needed.
>
> > How I wish we could have a much better idea of where that ice is gonna
be.
>
> Have you tried the icing predictions at ADDs?
>
> http://adds.aviationweather.noaa.gov/icing/
>
> (click the radio button to correspond to your time in the clouds, then the
> altitude level on the left to see the icing predictions. A bit more
> detailed than the generalized airmet Zulu.)
>
> Also, from what I have read in the latest issue of IFR Magazine, early
2006
> there will be a much more detailed icing forecast to replace the
> broad-brushed airmet Zulu. This will certainly be helpful in your case.
>
>
> --
> Peter

[Lynne]

Did you by chance ask the briefer at what altitude the inversion was
at? Keep in mind that an inversion is simply temperatures getting
warmer rather than dropping the higher you climb for some given block
of altitude. It may be one degree, or ten. It's not a specified
variable.

[John Doe]

"Paul Folbrecht" > wrote in message
...
> Did a short trip yesterday from MWC to OSH with the gf, just to go, about
> 3PM. Was planning on cruising at 3 to avoid ice in the clouds, which were
> not far about that at all. Briefer tells me there's an inversion aloft,
> and the freezing level is at NINER. Cool, great! Filed for 4, planning on
> getting actual the whole way there. On the climb, notice the temp
> dropping slowly the whole way. Inversion? Where is it? Into solid IMC
> around 32-3300, as expected. Temp is around 30 now. At 3800, it's a
> little less, about 28. I thought, what am I doing? I'd promised myself,
> recently, to stay out of the clouds below freezing (even though I've done
> it a number of times and never picked up ice I couldn't deal with by
> getting lower, out of the clouds or >0.). I called approach and asked for
> and got 3. Back to near VFR - very hazy, very poor vis, but not in cloud.
>
> So, what was up? The forecast was wrong, it seems. There was definitely
> *a* freezing level way below 9. May have been an inversion ABOVE that,
> and another FL at 9, but what the heck good does that do me? The briefer
> outright ENCOURAGED me to fly in the clouds - in fact he encouraged me to
> get on top and give him a pirep (tops around 5-6). (Of course I know that
> matters for nothing but it makes you think!)
>
> Thoughts about that?
>
> This got me to thinking once again about IFR and icing conditions (this
> topic hasn't ever been discused in this NG, has it? cough cough). As I
> said, my new rule - which is the smart way to do things - is to just stay
> out of the clouds below freezing in my very non-known-icing certified 152.
> I formerly took the more common position that I'll fly in cloud as long as
> there's an out - if I know going lower will get me out of icing and keep
> me above MEA. Then, a few weeks ago, I ended up coming into MWC from JVL
> with what was supposed to be 3000'+ ft cigs. Weather (snow) came in
> early - just a bit early, 1/2 hour, to be fair - and I ended up in actual
> almost all the way with no where to go (no ice, luckily) and doing the VOR
> 4 with 1600' and 1.
>
> Thinking about the whole thing later on unnerved me as I realized just how
> screwed I'd have been if I'd started getting ice enroute. Temps were
> right in the zone, around 25-27. There was no way the cigs were above the
> MVA (I was direct) or the OROCA for that matter - what to do? Tops were
> way up there. Declare and descend to 1000-1500' agl? I probably would
> not have been prosecuted, as WX was not forecast, but no fun would that be
> in any case!
>
> Thoughts on all this? Other than the obvious?
>
> How I wish we could have a much better idea of where that ice is gonna be.


I look for all the PIREPS I can get (in addition to everything else)
chances are I'm not the first one whose gone flying through the clouds I'm
worried about.

[William L.Snow, PE]

Here is one for you. On approach to Nashville, last week, cloud tops 4000
msl, bottoms 1800 msl, temp 35 deg F at 4000'
I started the approach, ATC descended me to 3000' for the downwind leg
vector. After about a minute or so I noticed clear ice on the windshield and
wings. I queried ATC, no one else had reported ice in the area I was in nor
was it forecast. I asked for lower and was informed that the mea was 3000'
msl and lower not possible. I advised that I needed to go back to 4000' msl.
ATC approved and back up I went to 4000 msl to shed the ice.
Lesson Learned...ice builds up VERY fast. Act fast. Make it right. No second
chances. We landed 10 miles away at Smyrna, TN no ice.

Bill Snow, PE, CP, IA, ASEL