To expand upon this (a bit of a play on words here) The
boots work by expanding outward and breaking the ice. If
the thin ice adheres to the boot, it can get pushed outward,
but not cracked and blown off as pieces. The pushed outward
ice can freeze with the boot inflated forming a cavity
between the subsequently deflated boot and the ice. The ice
then builds up on the outside of this ice cavity and the
boot can't break it off because it doesn't push against the
inside of the ice cavity.

That's the theory. I've been to several safety seminars at which this
theory was debunked, at least as to modern boots. It is also
discredited in the NASA icing video.

Jose
--
"There are 3 secrets to the perfect landing. Unfortunately, nobody knows
what they are." - (mike).
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