The US Army and USMC like the latest combat helmet even more than they liked the next-most recent improved model:
The U.S. Army and Marine Corps have found that their new Enhanced Combat Helmet (ECH) is even more bullet proof than expected. While testing the ECH, it was discovered that the machine firing metal fragments at the ECH (to represent shell and bomb fragments) could not fire fragments fast enough to penetrate. The ECH was supposed to be invulnerable to pistol bullets, and it was, but some types of metal fragments were expected to still be dangerous. So ECH was tested to see how well it could resist high-powered rifle bullets. ECH was not 100 percent invulnerable, but in most cases, it would stop anything fired from a sniper rifle. Overall, it was calculated that the ECH was 40 percent more resistant to projectiles and 70 percent stronger than the current ACH helmet.
The ECH is made of a new thermoplastic material (UHMWP, or Ultra-High Molecular Weight Polyethylene). It is lighter and stronger than the Kevlar used in the ACH and earlier PASGT and, it turned out, provided much better protection as well. The ECH will begin replacing the current ACH later this year, with 200,000 being eventually purchased. The ECH costs $600 each, twice as much as the ACH. But for troops under fire, the additional cost is well worth the additional protection.
Combat helmets, which appear to be low-tech, have been anything-but over the last three decades. Advances in the design and construction of helmets have been accelerating, especially in the last decade. For example, the current ACH (Advanced Combat Helmet) recently underwent some tweaks to make it more stable. That was required because more troops are being equipped with a flip down (over one eye) transparent computer screen. The device is close to the eye, so it looks like a laptop computer display to the soldier, and can display maps, orders, troop locations or whatever. If the helmet jumps around too much, it’s difficult for the solider to make out what’s on the display. This can be dangerous in combat.