I have difficulties judging whether flying through a cloud is dangerous or not. Every time I have been flying through some puffy clouds with some vertical development, it has been unimpressive. Maybe I have been just lucky. Let’s assume temperatures are warm enough such that icing is not a concern, or the time spent in a cloud is too short to accumulate ice. Turbulence and to a lesser extent hail are my concerns. So given the pictures below with red dots indicating the flight path, and assume there is no easy diversion possible left or right, would one fly in a SEP through the cloud or not? I understand there are certain distance rules from thunderstorm clouds, but many clouds are not yet fully developed thunderstorm clouds and vertical development is rather unimpressive.
A) This is an easy one. Clearly one would not fly through this bad boy.
B) But what about this one? What about fly over, acceptable?
C) But what about this one? What about fly over and to the left, acceptable?
D) And this one? What if one flies a mile to the left, almost in the clear? Vertical development is not impressive.
E) Again, not much vertical development
F) This one seems too dangerous. But what to the right, where it is clear and between the two vertical developments?
G)
H) Again, not much vertical development. Doable?
I)
J)
K)
L)
M) Almost at the top, so one is out of this cloud within 10 seconds. How bad are turbulences at the top of clouds?
Simple. All of these, don’t fly through them. Even if some of them might not be outright dangerous, they will all be very bumpy (pax will HATE it and not fly with you again) and potentially throw a lot of ice at you. If there is any way to avoid them, do it.
I flew through the top of an M the other day (B is similar) and there was no turbulence. It was a bad idea nevertheless as I am not IFR rated and I did not know how long I would stay in it. I was already at 9000’ with little climb power. I would avoid the others.
Simon
Still w/o an IR, going thru is not an option for me, but I have, over time tried all the alternatives that you mention to the pics.
Going above has rarely given me significant turbulance, neither has going between them.
Exception: when they were visibly building up fast.
Much worse is going under which I did in the beginning or sometimes have to do because it is a front I cannot go above. That is bad …
Whatever you see it’s better to avoid 
because you’ll usually pick some ice. You can pick it in few seconds and then wait for long time for it to melt down, flying at significantly lower speed. As rule of thumb it’s almost always better to overfly then to circumnavigate it if possible.
I’d fly through E G and H. B C I J K L over the top but with a good margin only (they can grow faster than I can climb). M if no pax and prepared (keep speed low, ready to lower the gear, deice checklist executed). I’d stay away from the others at least by the extent of their vertical development (20k feet → 20 nm).
I’d avoid all of these of there is any precipitation or if they seem to be building. If not, I’d fly through B, D, E, G, H and M, at the marked spots.
boscomantico wrote:
Simple. All of these, don’t fly through them.
ch.ess wrote:
Still w/o an IR, going thru is not an option
Emir wrote:
Whatever you see it’s better to avoid because you’ll usually pick some ice
Re: icing, you get a lot of it at the tops, even potentially at temperatures below -15C
A is obviously no-go. B C D and I have a large shower dropping out of the bottom so are probably hazardous. E and F and H are ok (bumpy), and F where there is a gap is certainly OK (just don’t do it with anything bigger like a part of a CB, due to lightning risk). G is dodgy because you can’t see what is above it. J K L similarly risky due to being borderline CBs and thus lightning risk. M is OK though probably bumpy.
If you find yourself in these coulds, fly slowly, well below Va. It also makes it a lot more bearable for the passengers, who may not fly with you again
