Nov 2010 – In restoring a HGU-2/P flight helmet from 1960’s USAF service, i carefully undertook some internal repairs and checked out the quality of the 50year old flight helmet liner.
As can be seen by my photos, the foam which was installed around 1960 when this helmet was made – seen by the white label details – is still pure white and so soft.
It is the same foam type as found in other P series flight helmet.
Only the edges were it has come into contact with light, moisture and air has it turned slightly yellow.
Most P helmets and other HGU-2/P if exposed to much environmental factors, have their foam a bright yellow and it is cracked/easily crumbles.
I am restoring this helmet with a MS22001 oxygen mask to make it as correct pilot set from 1960-1965 period , when they were then replaced by the HGU-2A/P helmet shell.