I agree it's not smart, but that's not the issue. What law would be
violated by flying my personal aircraft, which has no mention of icing in
the operating limitations, solo, in known or forecast icing conditions?


At the very least, the law that says "I will not do stupid things with
airplanes". The FARs word it thusly:

"91.13 (a) Aircraft operations for the purpose of air navigation. No person
may operate an aircraft in a careless or reckless manner so as to endanger the
life or property of another."


that is, "forecast" icing is now considered "known icing".
This is a change.

Cite the regulation.


You seem to be under the misconception that the laws are limited to statute.
They are not. Further, the laws are subject to "interpretation", and you don't
get to do the interpreting. The FAA does. The FAA has stated that "forecast
icing" will be interpreted as equivalent to "known icing". Actually this goes
back to 1974.

Avweb has an article at
http://www.avweb.com/news/airman/184265-1.html
that provides background and citiations of actual decisions that were made that
cemented this policy in place.

It goes on to say how the FAA and NTSB are not always in agreement, and the
NTSB can overrule the FAA in some cases. There's a lot of case law which you
can review. It is there that the "regulations" will be found - as precedent
that the FAA can choose from when they investigate an event.

If this doesn't satisfy you, ask the FAA directly by calling the FSDO. Get it
in writing, post it here, and then take a guess as to how well that will stand
up should there be an incident.

Jose

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