Paul J. Adam wrote:

The usual claim I've seen is that the Apache is designed to survive a
couple of hits from up to 23mm HEI (I assume with ZSU-23-4s in mind) -
that's not "23mm proof", but rather "won't crash immediately and can
limp back to base for repairs". Stuff like the gearbox able to run dry
for thirty minutes before eating itself, that kind of thing.

I'm sure there are still spots where one golden bullet can bring it
down, but it's a tough bird as helicopters go.

The Comanche was designed to take a 23 mm hit over anywhere its entire
structure* by using a composite Kevlar reinforced body shell as its
fuselage.
The whole thing was built like a Mosquito bomber, where the monocoque
exterior of its body formed the main structural strength of it, with
only minimal interior reinforcement and bracing. Basically a giant
plastic model helicopter where the fuselage halves are entirely hollow
inside.

* I'd like to see them try that on the cockpit windowpanes, BTW.
Ballistic polycarbonate that's bullet resistant is one thing; ballistic
polycarbonate that's proof against 23 mm HE fire is quite another.
Easy enough to test though...tape a hand grenade onto it, and pull the
pin. :-)

Pat