"Jose" wrote in message
.. .
The AIM presents the FAA's current official definition of "known icing
conditions". So any case law decided on the basis of prior explicit or
implicit definitions is no longer applicable.

Well, that might be true if the AIM were regulatory. It's not.

The AIM doesn't set forth regulations, but its subtitle is "Official Guide
to Basic Flight Information and ATC Procedures"; and it states in the
preface that it presents information that the FAA wants pilots use to
understand and interpret the regulations. There's no way the FAA could get
away with officially telling pilots to use a given explicit definition, and
then prosecuting them for complying.

But of course I'm willing to entertain evidence that I'm wrong about that.
Is there any documented example of a successful enforcement action taken
against a pilot for using a definition in the then-current AIM rather than
using some other, unpublished definition that the FAA proposes instead?

--Gary