Message 3621, Jul 28, 2001
Hi Maggot, Yep, it's early 60s time-frame (contract date is 1962). Milehigh has it nailed most succinctly. The SPH-1 was originally one of the many one-off types that sprang from the Bill Jack and CalMil designs (D-10 precursor) and used in the mid-to-late 50s. The SPH-2 was essentially a somewhat modified SPH-1 with this articulated visor (different edgeroll, etc.). I have a set of instructions, thanks to one of our forum members, that spells out the process for mounting this visor on the SPH-1, although the SPH-rarely is seen with the visor added retroactively. The SPH-2 was the new designation for the early (Bill Jack/Cal-Mil) design with this visor added, issued and used in the early 60s for the most part (ILC manufactured it under license).
It was intended for use as a rotary-wing helmet, as Milehigh pointed out, although the snaps on the shell seem to have enabled it to be used with an 02 mask. The liner is missing from this particular example, but it was a fabric or nylon covered sponge rubber circumferential inner line that could be removed to accommodate different sizes. I believe the helmet shell was issued solely in large and small sizes only, with a wide head size range being accommodated with those two shells through use of different sized inner sponge liners. Regrettably, this liner is frequently deteriorated completely, or missing altogether, since the helmet shell was not issued together with the liner (that was selected for the head the shell was to be used with, by a rigger). This is the same type liner found in the USAF HGU-9/P helmet used in the B-58 Hustler. Once again, it must be recalled that many different helmets were spun off from the basic original designs by Bill Jack. CalMil carried on the type, when they took over the Bill Jack operation. The HGU-16/P, HGU-9/P, and several other helmets used in both services are all related in this common ancestry.
The liners can still be found in separate, issue boxes (sometimes in excellent shape, but more frequently in poor shape, or with the foam completely rotted away to dust). A chin cup-mounted mic was used first with both helmets (as Milehigh noted), but a side-mounted mic was later in use. There are some excellent photographs of the SPH-1 & SPH-2 helmets in the JAFH book on pages 94 & 95.
To the best of my knowledge, this helmet was NEVER used in fixed-wing, fast jet type aircraft operations (strictly in rotary-wing). Finally, the visor lens, once dropped into position, was configured to meet the bridge of the wearer's nose fairly closely to exclude wind effects. There was little or no room to accommodate a mask nose section easily and the angle of the frontal curvilinear plane of the visor was also wrong for mating with a mask properly. This visor was not multi-positional, but rather had to be worn either full up or full down. It is one of the "must have" helmets in anyone's US Navy helmet collection, in my opinion, but hopefully one may be found with a liner (the one on eBay lacks the liner, unfortunately). Essentially, Milehigh pegged this one completely with his remarks.
Cheers, DocBoink