Frag Out! Magazine
Issue link: https://fragout.uberflip.com/i/958224
HELMET SHELL The PASGT helmet shells, according to MIL-H-44099 standard, were made of layers of Kevlar bound by us- ing a press and a 50/50 mixture of phenolic and poly- vinyl butyral resin. The shell had to be molded in a way that would ensure basis weight of the final product of 11.6 kg/m2 while the content of solid resin after mold- ing had to be at 15-18%, with the assumption of no free gaps inside the helmet. The remaining air was re- moved by exposure to a temperature of 160oC for 5 minutes. Only the dimensions of individual pieces of fabric that had to be put in the press were specified. Each manufacturer could use different formulas under the condition that the final product had solid density, fragments were not smaller than the ones specified in the standard, while in case of any change in the meth- od of production of the shell, the manufacturer had to send helmets for ballistic tests. Each mold had a stamp that would be extruded inside the helmet, on its top. It specified the year and the size as well as numbers from 0 to 9 (that is why we can notice "M-3" next to the size, where 3 is the mold number). Some compa- nies, such as Specialty Plastic Products (SPP), Gentex or Sioux Lake Manufacturing would put their logo next to the mold stamp. The helmet was to withstand an impact of a sub-caliber .22 round with speed of 2000 fps shot from an M1 or M2 Carbine. PASGT helmets have never been bulletproof. All the tests that can be found on the Internet where people shoot through the helmets are completely unreliable. A helmet lying on the ground reacts differently to a shot than a helmet on someone's head. Besides, every dent greater than 0.5 inch or every smallest sign of penetration would rather mean severe injury or death. Then, FS 34087 color rubber edge was sealed onto the shell. In case of many manufacturers, the color of the adhesive changes to dark brown after years of use, especially in the case of helmets produced by UNI- COR. Next, the holes for the suspension were drilled. Later, the shells were painted in FS 34087 color and the last layer contained quartz sand or walnut shell pow- der. The PII (Procurement Instrument Identifier) stamp was affixed inside the shell. The next stage was the attachment of the suspension in the shell by bolts and A-shaped nuts as well as of the chinstrap. Finally, the helmet was painted once more. Inside the helmet, un- der the straps of the suspension, manufactured would put the sweatband (packed in foil) and a small printed manual. Before use, the helmet had to be assembled, then camouflage cover with elastic band should be put on, and other accessories, depending on the needs. All helmets produced in the 1980s-1990s were painted in FS 34087. Initially, helmet shells were pro- duced in four sizes: Ä X-Small (8470-01-092-7525) Ä Small (8470-01-092-7526) Ä Medium (8470-01-092-7527) Ä Large (8470-01-092-7527) Over time, it appeared that the calculations con- cerning 99% of the requirements, in terms of sizes, were not accurate enough. It appeared that the even Large size is too small. The tests were conducted with- in the period from November 1987 to February 1988. After the analysis of another 8 consecutive anthropo- morphic tests since the times of data used in the first half of the 1970s, it was determined that helmets of 3.26% soldiers were too small, even when they were given the largest size. During the tests, it was deter- mined that even after decreasing the safety limit from 13 mm to 10.5 mm, still 0.5% of soldiers would be out- side that limit. On the other hand, the usage of helmets with lower safety limits did not seem to be a good idea. Another problem was the low number of soldiers that could be used as subjects for measurements. It was estimated that there were ~3600 soldiers, whereby not all of them were aware of the imperfect fitting. Although the method used 15 years before involving the 3D Nu- merical Surface Descriptor seemed right, at that time, in order to recalculate the dimensions of helmets to the X-Large size, math and regression equations were used. The helmet in XL size (8470-01-300-3819) was fi- nally introduced on 14 May 1989 and the only contract in the 1980s-1990s, DLA100-90-F-EC43 was signed no sooner than on 15 February 1990. Total of 12,000 XL helmets were produced. Not all of the sizes were produced in all years. Siz- es XS, S and L were produced throughout the 1980s. Then, the production stopped. In the case of the XS size, the last contract was DLA100-89-C-4035 (19 April 1989), the S size: DLA100-88-C-4397 (19 April 1989), while the L size: DLA100-90-F-EC43 (15 Febru- equipment