Sikorsky S-76: Ask Nick Lappos

[DECUFAULT]

As an alternative to the use of the Sikorsky approved windshield types, operators with aircraft possessing
cast acrylic windshields can attain an equivalent level of impact tolerance by limiting the maximum speed
of the helicopter to no more than 109 knots. A field check for the presence of cast acrylic is available

and is provided in Enclosure (1).

Up to you !!