The FAA known ice also means that aircraft was designed such that
things like fuel vents, etc are vented in such a way that they don't
ice up. Its more than just the deicing system.

And, as I understand it, the FAA has really tightened up on "known
icing certification since the Mooney 231 was certified.

From what I've heard, it (and many other planes) would no longer pass
muster under current standards.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
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