H-4 helmet Latest update 20 January 2007 The design work on the H-4 helmet appears to have started late 1952 or early 1953. By
late 1953 its development has progressed so far that it was offered to the Royal
Australian Air Force as part of their helmet acquisition programme. It is not fully clear
when the H-4 entered US Navy service but 1954 appears to be a good guess. ment straps you can see the studs for attaching goggles. Pictures © Peter Bennethum "flightjkt" I have not seen any reports on the H-3 shortcomings that
led to the development of the H-4, but the following brief description of the H-4 helmet
from a US Navy training manual from around 1960 indirectly indicate what they were. The
training manual mentioned that the H-4 helmet is basically the same as the H-3 with the
following exceptions: It suggests that the H-3 helmet did not offer sufficient
protection from a hard head-on blow, the lack of protection being caused by a combination
of an adjustable headband that was not stable enough and a shell that did not cover enough
of the forehead. The nylon mesh centre panel on the inner liner was a late addition to the
H-4; the first liners only differed from the H-3 inner liner by having two male studs on
each side for attachment of oxygen masks with Pull-the-Dot fasteners, whereas the H-3
liner had three male studs on each side of the same type as used by the USAF. The attempt
to design the H-4 with improved stability over the H-3 do not appear to have been
particularly successful. The modification with the stabilising straps appears to have been
widely applied to the H-4, which became the standard anti-buffet helmet from around 1954
onwards. The H-3 and H-4 continued side by side as a sort of
Duke's mixture of H-4s and H-3s having H-4 liners. From late 1956 the APH-5 helmet became
the primary helmet for high performance aircraft so the H-3 and H-4 were relegated to less
glorious use. Both the H-3 and the H-4 were still mentioned in the 1964-dated NAVPERS
10358-B PR training manual. By that time the H-3 and H-4 helmets were primarily used by
crewmen in multi-place aircraft. They were no longer under procurement; and when
replacement was necessary, they would be replaced by either the SPH-2, the BPH-2, or one
of the APH types, whichever was applicable. The H-3 and H-4 were no longer mentioned in
the 1967-dated NAVPERS 10358-C. It may therefore safely be assumed that for all intents
and purposes the H-3 and H-4 disappeared from USN service between 1964 and 1967.
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