Icing

C J Campbell wrote:

Descending out of a layer of freezing rain does not likely to work because
the cold layer may go all the way to the ground and the water will not have
formed ice pellets before reaching the ground.

That was an excellent posting, but I'd just like to add that descending can
work very well if you know for certain that the temperature below you is
much warmer, say, 5-10 degC (you can confirm the surface temp by tuning in
each ATIS as you pass it, something that I always do in cold IMC). That is
typical of spring in central Canada (and, presumably, the northeastern U.S.)
-- In Ottawa we get freezing rain or ice pellets on the ground only a few
days a year, but we have supercooled large droplets aloft for much more than
that, and they're especially problematic in early spring when we're right on
the boundary between the Gulf and Arctic air masses.

However, it is not as if the rain is invisible -- you can see rain shafts
from quite a distance. Obviously, visible rain shafts in areas of below
freezing temperatures should be avoided. The real problem comes when you are
IFR and cannot see the rain before you encounter it. If you are not equipped
for dealing with icing conditions the best strategy is to not fly into any
cloud where the temperature is near or just below freezing.

Unless you have a lot of outs, of course, such as known warmer air below
(above MEA) and/or usable approaches nearby. Typically, the cloud tops are
not high in the winter, so you'll be in IMC twice on a long cross country:
climbing up through the clouds on departure, and climbing back down through
them on arrival. In the spring, things are trickier, since the cloud tops
can be well up in the oxygen altitudes. Either way, icing does cause me to
cancel some trips.


All the best,


David

Freezing rain is not a normal or common thing. Just because you fly in
the winter and its raining does not mean you will get freezing rain.
Freezing rain is a very serious thing and I don't believe any
airliners are even certified to fly in it. Freezing rain does mean
there is warn air above though. Anytime you fly IMC in winter you need
to always have an out. If you fly IMC you WILL someday get ice. Its
just not realitic to say anything else unless you use your IFR ticket
for nothing other than bragging rights in the FBO. The FAA's approach
to teaching icing is totally unreasonable and they need to go back to
teaching how to determine where ice may be and how to escape. This
modern idea of "if ice touches you, you will die right away" is not
helpful. Different types of situations give different types of ice.
Knowing how to determine what type if ice may be where and having outs
is really the only thing you can do. Today, there is no real way to
forcast ice (airmets are really useless and have next to no indication
of ice or lack of it).

-Robert, CFI (and frequent IFR pilot).



"Marco Rispoli" wrote in message .net...
You are flying IFR ... and you fly into a cloud. You are deep in
winter and
you realize that you are in freezing rain.

In a minute your plane will be unflyable. You need to decide quickly what to
do and you can't start thinking or reasoning about what's the best course of
action: you gotta be ready with the course of action already and it needs to
be instinctive to bug out of Dodge.

Robert M. Gary wrote:
If you fly IMC you WILL someday get ice. Its
just not realitic to say anything else unless you use your IFR ticket
for nothing other than bragging rights in the FBO.

That might be a little extreme -- even up here in Ottawa, Canada, the
freezing level is typically around 10,000 ft in the summer while the MEAs
can be down around 3,000 ft -- but your point is very well taken. To avoid
ever picking up even a trace of ice, you'd have to fly VFR only for almost
half the year in Canada or the northern U.S. (and even then, only with a
clear sky).

The FAA's approach
to teaching icing is totally unreasonable and they need to go back to
teaching how to determine where ice may be and how to escape. This
modern idea of "if ice touches you, you will die right away" is not
helpful.

I agree very strongly. It's good to warn people to be careful, but if you
make them panic unnecessarily you're risking an accident from some other
cause (say, CFIT during a hasty diversion). Through all its bad acting, the
NASA icing video is somewhat helpful, since it does show people dealing
practically with icing in the air (i.e. the pilot of a single has to ask for
a descent forcefully when ATC brushes him off on the first call, but he
doesn't get to the point of declaring an emergency).


All the best,


David

David Megginson wrote in message . net.cable.rogers.com...
Robert M. Gary wrote:
If you fly IMC you WILL someday get ice. Its
just not realitic to say anything else unless you use your IFR ticket
for nothing other than bragging rights in the FBO.

The FAA's approach
to teaching icing is totally unreasonable and they need to go back to
teaching how to determine where ice may be and how to escape. This
modern idea of "if ice touches you, you will die right away" is not
helpful.

I agree very strongly....

Hear, hear.

Much more so than the "VFR not recommended" the "airmet for icing"
issued for much of the colder half of the year in the Northeast US is
largely discounted as paper-trail CYA-ing.

OTOH, I hear a lot of briefers in the winter say, "we've got the
airmet but there's no pireps and it doesn't look like it's going to
cause any trouble where you're headed." Sometimes seems there's an
unwritten law of sorts in effect here.

-cwk.