Having no ice protection other than a TKS de-iced prop, I normally avoid fronts in the terminal areas, but will cross them if the satellite IR images show that the cloud tops are not likely to be above the aircraft operating ceiling (FL180-200).
However I know many pilots do just fly through them, and take a risk, with the escape routes being either a descent into warm air (if icing is found) or a 180.
Can anyone describe their strategy?
I find it very hard to judge the vertical extension of a cloud cover from below. This is the deciding factor when one considers to climb into clouds, trying to get on top. The IR images mostly help to determine whether one will encounter clouds enroute but not when one is below those clouds. The thicker the clouds, the more light they absorb but this also depends on the type of clouds. A thin cumulus can absorb a lot more light than a 8000 ft stratus layer. And other than the rare balloon ascends, there is no way to find out whether there is "free space" between two overcast layers.
In today's weather with < 0°C on the ground, these things are even more important as there is no way to get rid of the ice before landing.
Another thing I have been asking myself for some time: my airplane (TR182) is restricted to FL200 as a limitation in the POH even though it can easily do FL240 and more (climbing at ca. 650fpm there). It was flight tested for FL240 but then limited to FL200 for marketing reasons (to not compete with the more expensive T210). When I'm cruising in FL200 and I encounter nasty clouds, should I turn around and abandon the flight or climb to a comfortable FL210-240? I know for a fact that my airplane can do it and I know that one can deviate from the limitations in the POH when safety is concerned. There can always be reasons why abandoning the flight could be considered less safe then continuing at a higher altitude. What would you do?
I find it very hard to judge the vertical extension of a cloud cover from below.
You can simply ask ATC how high the cloud tops are. They are typically happy to oblige - if not right away, then within a few minutes, once they have spoken to someone flying up there.
Another thing I have been asking myself for some time: my airplane (TR182) is restricted to FL200 as a limitation in the POH even though it can easily do FL240 and more (climbing at ca. 650fpm there). It was flight tested for FL240 but then limited to FL200 for marketing reasons (to not compete with the more expensive T210). When I'm cruising in FL200 and I encounter nasty clouds, should I turn around and abandon the flight or climb to a comfortable FL210-240? I know for a fact that my airplane can do it and I know that one can deviate from the limitations in the POH when safety is concerned. There can always be reasons why abandoning the flight could be considered less safe then continuing at a higher altitude. What would you do?>
And if you are N-reg at least and you need to deviate from the POH for safety (icing) concerns, I guess another considerations whether the POH also prohibits flight in "known icing conditions"....(as opposed to "known icing".... Ref FAA clarification here
AQ
On a quick read, that FAA opinion basically says that icing is icing when you see the ice accumulating, no?
So, if you start collecting ice, you are supposed to get out of it, which is what one would do anyway - well once it gets to a certain amount which is a matter of judgement.
I don't know if there have been later FAA CC opinions, but some of the earlier ones were outrageous and effectively banned flight in IMC below 0C unless FIKI certified.
So what is the point, legally speaking, of a FIKI certified aircraft? I suppose that allows you to carry on with the flight if you see ice accumulating.
In reply to Achimha's question, I would climb, without question. VMC on top is nearly always the best place to be. You might just need 8.33 however 
But the oxygen situation at FL240 needs very careful management; much more so with passengers. You will need masks (not cannulas) for all. I fly with cannulas to FL200 and with the O2D2 demand regulator they work very well (95% O2 achieved) but I don't think I would try FL240 even if I could climb up there.
I that the letter indicates that known icing is that which is physically observed....but it also makes the point that some POHs refer to known icing conditions...ie a more onerous limitation....of course it is only relevant if you are ever called to account....which I presume is an unlikely result of climbing above the aircarft's certified ceiling?
Other than hypoxia causing some other breach, I can't we why it would ever be a bad idea to climb out of an icing layer - and I certainly can't see how it would ever be detected. I suppose only risk would be if you can't climb through it and end up with even more ice.
If you normally operate up to FL180-200, do you have O2 masks to cover that emergency climb? (assuming the aircraft is capable - irrespective of certified ceiling)....is it practical to change from cannulae to masks inflight?
(and by emergency, I just mean an unplanned event)
Very interesting to read about experiances of flying high in a Cessna 182. I own a Cessna T182T which has also a service ceiling of FL 200. On a flight over the alps the route was blocked by a wall of clouds. PC-met did predict TOPS at FL 180 which seemed easy to cope with. But arriving there south of Zurich the real scene was another. I asked for a climb to FL 200 and then to FL 210 which was not enough when I heared Lufthansa asking for FL 260. Now it becomes clear that I wouldnt make it on the flight planned route. With a deviation of 40 nm I was able to circumnavigate the wall. While climbing to FL 210 the climb rate was 500 ft/min. with all temps in the green, OAT -24°C. At this point I noticed that I would be able to climb higher but I was anxious about having only one mask for me and no mask for the copilot. Also I considered the possibility of fuel icing at these low OAT. But so far I understand it is not illegal to fly over the service ceiling of an aircraft ? I follow Peters recommendations on planning the flight but determine the TOPs is very difficult and PC-met is not reliable. What do you think about ?
I always try to avoid cruising in IMC as much as possible. I'll rather cancel or postpone a flight rather than deal with turbulence and possible ice. For me, the IR is really a "punch-through-clouds-on-arrival-and-departure-rating".
Re the FAA icing definition: I've lost count of the changes that have taken place. Anyhow, it seems to me that they take an increasingly dim view of icing in small non-FIKI airctaft. I certainly don't think it is "known icing is when you encounter ice, so once you encounter it, you have to get out". Lately, several pilots have been caught doing this, i.e. they reported icing to ATC and simultaneously requested a level change and proceeded to destination. No disruptions to other traffic. Nothing. And still, after landing they have been interrogated by the relevant FSDO and penalized as well.
Here, in Europe, the tendency seems to be the same, i.e. contollers (particularly in Germany) are becoming increasingly "investigative" as soon as anything ever so slightly out of the norm happens. I have long ago resolved to not tell ATC a single word re "icing", even if I encounter it. IME, any request for a level change will normally handled just as quickly without the "i-word". Sometimes, AtC will enquire as to the reason for the request, and I'll just say "because I prefer to fly at level xy".
On a related subject, I would never tell ATC when I have a minor, non-critical technical problem. Nowadays, any report of this kind, especially when slightly badly worded, will get an immense machinery going and at the very least, will get the fire crew deployed at your destination airfield, questions asked after landing, etc.
Is acting like this (i.e. not reporting minor troubles like light icing) in the interest of safety? Certainly not, but IMHO it's the more intelligent way to go, in today's world.
