Helmet (White)

[handwritten legends]
22?/?????72
Mk3C/4255
523
S/L INVIS[?]

The Mk.3C is an RAF Flying Helmet of the late 1970’s. It supersedes the Mk.1A/G also the MK.2A & 3A/B type helmets and covered in one basic design a helmet for aircrews concerned with low & high altitude (rotary & fixed wing) with or without ejection seats. The rigid outer shell of moulded glass fibre resin is provided with a lining of shock absorbing cork. An internal cradle of nylon webbing minimizes the transmitted force & distributes it over as large an area of the head as possible. The soft comfortable padded lining is replaceable & its attachment to the shell forms a windproof seal, which together with the chinstrap, visor & oxygen mask ensures security of the helmet under severe blast conditions. The attachment of lining to shell is so contrived that the lining can be removed either for replacement or for access to the avionics equipment or other interior fittings. A single miniature telephone feeds the signal via sound tubes to acoustically designed ear capsules, the capsules on an adjustable light spring wire suspension can be held away from the face when donning the helmet but seal snugly on the head when tensioned by the chin & neck strap. The microphone plug is conveniently situated low down on the cheek. The Mk.3C Helmet has a double visor system with a side mounted polycarbonate inner visor for blast & bird strike debris & an outer independently positioned anti-glare visor, both superimposed on common pivots. A side mounted locking device holds down the inner blast visor.
The mounting bracket on the top/front of the helmet would be used for the attachment of devices such as Night Vision Goggles; it is marked "SME.55411”. The helmet has other markings some of which are barely legible.
The markings determine the helmet type and that the NVG bracket was for the US Integrated Night Vision Imaging System (INVIS)