flying into snow showers without deice

Mike Rapoport wrote:

If it is melting then the temp is above 0Cand the water content isn't
supercooled and it won't stick. It can certainly clog the intake though.

Well, it CAN stick as I've collected it a number of times on 172 and 182
airplanes. I can't explain for certainty why, but I'm guessing it is
the combination of water and ice crystals in the same snowflake that mix
and stick upon impact.

You don't fly much in PA in the winter without encountering snow of all
forms (and there are many forms of snow). Most doesn't stick, but some
does if the conditions are right.

Matt

Well with four years of flying in Montana I will tell you that no
matter what type of precipitation, if the static air temperature (SAT)
is anywhere from +3 degrees celsius to -17 degrees celsius and flying
in IMC the potential for icing exists.

I fly about 800 hours a year in pistion twins certified for moderate
icing conditions. The worst icing encounter I ever got was in a heavy
snow storm, about 4" in 10 minutes. Did the boots work, yea, but did
the ice go away, nope!

Also, if flying on the lee side of mountains or over water the
potential goes up exponentionally!

If you don't have an airplane certified for icing conditions please
don't becomen a statistic and go fishing, your life and the life of
your passengers aren't worth it.

Curtis
Montana

Oh, If you do get into the ice, either move your airplane 180 degrees
immediately where there was no ice, this would constitute an emergency
in an airplane not capable of flight into known icing.

Or move the airplane up or down 4000' will guarantee exiting icing
conditions, however, in my experience moving 2000' feet will exit those
conditions.

I haven't had to declare an emergency due to ice, yet, however on
several occasions I've been in mountain wave with ice accumulation and
haven't been able to maintain altitude, however, ATC was kind and
issued a block altitude and I was able to drift up and down at my
minumum controllable airspeed. Yes this was in a twin airplane capable
for flight into known icing conditions.

Even with the slightest amount of ice you need a way to rid the ice off
the windscreen to see to land. We have a plane with alcohol windows
and I guess the alcohol wasn't fresh and contained water, so it just
made matters worse. Guess it's why we get paid the big bucks to fly!

Best of luck and be safe and smart.

Curtis

"CloudyIFR" wrote in message =
oups.com...
=20
=20
Or move the airplane up or down 4000' will guarantee exiting icing
conditions, however, in my experience moving 2000' feet will exit =
those
conditions.
=20
Curtis


Normally that's true, but there's no such guarantee.
I've seen weird inversions giving rain and multiple freezing levels
spanning a vertical range of 10,000 feet.

From a strictly theoretical viewpoint it is diffucult to see how snow can be
both melting (implying temp0C) and freezing to the wing (implying temp 0C)
at the same time. NASA studies have never be able to create icing above 0C.

Mike
MU-2


"Matt Whiting" wrote in message
...
Mike Rapoport wrote:

If it is melting then the temp is above 0Cand the water content isn't
supercooled and it won't stick. It can certainly clog the intake though.

Well, it CAN stick as I've collected it a number of times on 172 and 182
airplanes. I can't explain for certainty why, but I'm guessing it is the
combination of water and ice crystals in the same snowflake that mix and
stick upon impact.

You don't fly much in PA in the winter without encountering snow of all
forms (and there are many forms of snow). Most doesn't stick, but some
does if the conditions are right.

Matt

Mike Rapoport wrote:
From a strictly theoretical viewpoint it is diffucult to see how snow can be
both melting (implying temp0C) and freezing to the wing (implying temp 0C)
at the same time. NASA studies have never be able to create icing above 0C.

I can't explain it, but I've seen it happen enough to know that it does.
I'll venture a guess that it is due to the fact that not all of the
snowflake is melted. So, part of the flake is still below freezing and
part is above. Mash it against the wing at 150 MPH and the energy may
well equalize fairly quickly causing freezing of what was water a moment
before. Could well be similar to the way super cooled droplets work.
They are below freezing, but still liquid. Yet the slightest impact and
they freeze instantly.


Matt

Perhaps a partly melted snowflake hits the wing or another partly
melted snowflake, and the slipstream preferentially carries off the
more energetic molecules, leaving the remainder to freeze together?

Jose
--
Money: What you need when you run out of brains.
for Email, make the obvious change in the address.

On 5 Feb 2005 06:33:10 -0800, "CloudyIFR" wrote:

If you don't have an airplane certified for icing conditions please
don't becomen a statistic and go fishing


Would that be ice fishing?


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

On Sat, 05 Feb 2005 15:49:32 GMT, "Mike Rapoport"
wrote:

From a strictly theoretical viewpoint it is diffucult to see how snow can be
both melting (implying temp0C) and freezing to the wing (implying temp 0C)
at the same time. NASA studies have never be able to create icing above 0C.

I think what is happening is that the wing is colder (cold soaked fuel) or
the OAT changes -- perhaps with a slight climb.

I recall departing SWF one morning when it was snowing on the ground. But
the snow was melting. At about 20' AGL, the snow that had melted onto our
wing suddenly froze, and we had these little ice bumps all over the upper
wing surface.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Ron Rosenfeld wrote:

On 5 Feb 2005 06:33:10 -0800, "CloudyIFR" wrote:


If you don't have an airplane certified for icing conditions please
don't becomen a statistic and go fishing



Would that be ice fishing?

Probably, but I never did understand why anyone wanted to catch ice?


Matt