Just to correct one thing, without wishing to be pedantic, the original tail boom heat shield, as designed by CTGM the French company who must have made a fortune by fitting the first arriels as a private venture, was metal bolted over a thermal heat blanket, which was bonded to the tail boom.
Sikorsky mandated that this be removed at set hours for a tail boom inspection, this of course would have destroyed the bonded blanket. All the operators said,"you must be joking", so Sikorsky bowed to pressure and removed this requirement.