A Lieberman wrote:

I'm going to answer these before I read the other replies, to avoid
prejudicing my own answers. Apologies for any duplication.

Question 1 on Sleet. In my case, it was 43 on the ground, and on my climb
to my altitude, the temperature remained well above 32 while I was in IMC.
I climbed to 6000 which was my designated altitude. I broke out at 5,500.
How far up can sleet be created and not melt before hitting the ground?
There was a layer of clouds above me. Seems that from the ground to 6000
feet, I came across some hardy sleet pellets to survive that long in above
freezing temperatures?

I fly some IMC in winter here in central Canada and the NE US in my
Warrior, and do occasionally encounter ice at altitude. Still, I would
not take off if I saw sleet or ice pellets, period. I probably
wouldn't even try it in a twin with boots, due to the risk of severe
clear.

Question 2 on icing. Had I not climbed up like I did, I would have never
seen the ice on the wings or stabilator. I now know to look on that
temperature probe for first signs of icing as I did today, but will it
readily show up in IMC without reflections of the sun?

Clear icing will show up easily on the probe, even at night, because it
changes the shape of the tip. Rime icing, maybe less so.

Figuring on 500 feet per minute
descent, for me, 1500 feet is rather thick for 3 minutes.

You might not want to descend that slowly through an icing layer. I
don't think there's any reliable measure for how slowly or fast you can
ice up -- I haven't had this happen to me, but I know people who've had
the windscreen ice over almost instantly, as if someone threw a bucket
of paint on it. You have to be prepared to land in a slip, looking out
the storm window, if your defrost cannot clear it.

If you're going to have to descend through a possible icing layer, set
up everything in your favour beforehand: carb heat on, pitot heat on,
defroster on, a big post-it note on your flap switch or handle saying
"DON'T TOUCH" (flaps can cause a tail stall if you've encountered ice),
and a fairly steep approach slope. Try to keep the throttle as far
open as you can and don't slow down too much. Oh, did I mention?
Don't touch the flaps.


All the best,


David