From the M3 to the M4, and lots of intermediate steps, the M4A2 was not quite the apex of American flak helmet but it led directly to the M5
Introduced in 1944 is the M4A2 aircrewman's helmet.
Made of plates of Hadefield manganese steel this low-profile helmet provided head protection as well as accommodation for headsets.
It is covered over all with olive drab fabric
Keepers at the back secure goggle straps.
The label on this helmet is very much intact and readable.
Of interest is the fact that this helmet, unlike nearly any other, has no suspension but fits snugly over the leather flyers helmet.
This specimen in my collection is in very fine condition save for one small hole in the interior fabric and...
a particularly cracked and dry chinstrap.
The ear cups are fastened by fabric, rather than metal, hinges with heavy-duty stitching.
The M4A2 in action.
Photos can be found of the M3, M4, and M4A2 being utilized by tank crews, and these helmets are often misidentified as primarily armored vehicle crewmen helmets.
Note that at the beginning of this post I said that the M4A2 represented the "apex" rather than saying the "acme". The two words mean the same thing; I just didn't want to conjure up this image:
And just where is Wiley Cayote's trusty M4A2 in this picture?
