Pentrating Towering Cumulus Clouds

"Judah" wrote in message
. ..
"Ron McKinnon" wrote in
newsG%8e.1066820$Xk.925695@pd7tw3no:


"Doug" wrote in message
oups.com...
I was in one once. A towering Cumulus. A big dark one. Weather said
just rain, no thunderstorms. It started raining. Then I lost some
altitude. Looked up and my airplane was coated with ice! Clear, but
ragged ice, about 1/2" thick on all forward facing surfaces.
Fortunately I had warm VMC under me, so I descended and shed the ice.
I don't fly into dark Cumulus clouds anymore. Only reason I did that
time is I was pretty ignorant of weather.

How on earth could you be an Instrument rated Pilot, or even a
non-instrument rated pilot for that matter, and be 'pretty ignorant
of weather' ???

I was just happy to have a
clearance and be able to fly in actual. I was in and out of IMC. Here
comes a big dark one. In I went. Coulda been worse, coulda been
hail....


I suspect that his level of "ignorance of weather" was that he was unable
to accurately predict the conditions inside that dark towering Cumulus
cloud he flew through.

The level of ignorance implied by my post was the level of ignorance
stated by the original poster 'Pretty ignorant about weather", and the
stated actions of that poster

I also suspect that most pilots, VFR or IFR, have been in the
same boat at some point after their IFR training, especially
since it is not a pre-requisite to receiving the instrument rating.
We are mostly taught to depend on forecasts and spend very little
time during training on learning to properly identify cloud formations
from actual pictures or live representations, and to understand what
to expect within each type of cloud.

How can you 'depend on forecasts' alone? They are a sketch of
what someone thinks is *likely* to happen. They are not cast in
concrete statements of what *will* happen everywhere in the given
area. And even if they're right-on, for the most part, they can still
miss very localized or short-term events. You can't rely on the
forecasts alone.

And, in any case, you need to know enough about weather to
understand the forecasts so that you know how they might impact
you. This implies a certain understanding of the characteristics
of things like clouds.

During VFR training, you learn to just stay away from them.
And during IFR training, you get pounded about the extremes
(CBs and Stratus clouds) but there is really inadequate training
of the stuff in the middle - probably because the stuff in
the middle varies so widely.

If you know that you should stay the hell away from CBs, you
should know to stay away from "big, dark, TCUs" as well.
A big, dark, TCU, depending on how big and dark it is, for
your intents and purposes, should be considered the same
as a CB. A cloud doesn't just turn into a CB and becoume
dangerous because now it's a CB; it becomes dangerous the
bigger it gets. A big, dark TCU, should probably be considered
as dangerous as a new CB.

Can you accurately predict conditions inside of a towering CU
unless you get inside of it? There are different conditions even
within the same cloud that depend on many factors tat include
pressure, elapsed time, wind speed, humidity levels, etc. So
while one dark TCU may produce hail, rain, and ice, the next
dark TCU might be fairly uneventful and produce some
turbulence as you enter and exit and that's all.

You don't need to know what a grizzly bear had for breakfast
to know not to poke him with a stick. Respect him just 'cause
he's a grizzly bear.

'Accuracy of predictions' is a red-herring, here. Accurate
predictions of conditions inside a TCU are not required.
Just know that if they're big and dark, they're probably nasty.
If you wouldn't penetrate or fly in the vicinity of a CB, you
should probably accord a 'big dark TCU' similar respect.

I think most people are fairly ignorant of weather, even if we
think we are experts. Otherwise the meteorologists would
never be wrong, and the rest of us COULD just depend on the
forecasts...

I suggest that meteorologists are not absolutely wrong as much
as you think. Or as much wrong as you think. But even so, this
does not speak to ignorance of weather, nor or weather processes,
but more to the difficulty in predicting very far into the future the
behaviour of a largely chaotic system such as the atmosphere.

Pilots do not need to be degreed meteorologists, but they do
need to know enough to understand what meteorologists are
telling them, and they do need to know the *basics* well enough
to expect that flying into a 'big, dark TCU' is very likely a
problem.