A Marine lance corporal wearing an Enhanced Combat Helmet (ECH). Source: US Marine Corps Photo by Staff Sgt. Dengrier M. Baez/Released
The present and future of US combat helmets
At the end of the last century, researchers in the private sector, the U.S. Army Research Lab, and the U.S. Army Research Development and Engineering Command conducted research on new, lightweight ballistic fibers that could provide superior performance to the Kevlar used in the PASGT helmet. These development efforts focused on high-molecular-weight polyethylene ballistics fibers:
Polyethylene polymer materials had different performance characteristics than para-aramid polymer materials. Above certain temperatures, para-aramids (classified as thermosets) polymers broke down, lost their properties, and could not be remolded back into their original states when cooled. On the other hand, above certain temperatures, polyethylene polymers (classified as thermoplastics) broke down but could be remolded into their original state when cooled.
The application of high-molecular-weight polyethylene fiber material in helmets created the misperception that helmets might easily lose their form under ballistic events and potentially jeopardize soldiers’ safety. Ultimately, the advantages of polyethylene helmets for reduced weight and greater ballistic capability outweighed this concern. The basis of future Army helmets—both the ECH and its eventual replacement, the Soldier Protection System future combat helmet—remained high-molecular-weight polyethylene technology.
Started in 2009, the development program for the Enhanced Combat Helmet (ECH) initially provided two recommended options based on the use of polyethylene polymers instead of Kevlar:
Nevertheless, key stakeholders in the project pushed for both benefits. Studying 77 damaged ACH helmets worn by personnel who had taken bullets to the head showed that of those who experienced a complete penetration, 73.7% died – whereas there was a 0% fatality rate if the bullet only partially penetrated the armor. There is no doubt that a new helmet that can stop or sufficiently slow a modern rifle bullet will save numerous lives.
After failing initial testing in 2009 and 2011 based on a “pass-fail” standard, the standards of the program were revised to one based on statistical confidence: “the ECH had to attain a 90 percent probability with 90 percent confidence that the helmet will not be penetrated, according to Col. Mike Manning, program manager for Infantry Weapons Systems at Marine Corps Systems Command.”
The result of the program has been something of a compromise. In 2017, the Army awarded a $98 million contract to manufacture 293,870 examples of a separate Advanced Combat Helmet Gen II (ACH II) while also rolling out the ECH:
The current ECH serves as a jumping off point for the development of The Integrated Head Protection System (IHPS), which Popular Mechanics described as “straight out of science fiction.” For the first time, US service members will field a helmet that offers complete head protection, including the face:
In addition to standard cranial protection, the IHPS includes a mandible, visor, night vision goggle attachment device, rails and a modular ballistic applique. The helmet offers increased blunt impact protection over the current ECH Army helmet. It is five percent lighter, offers passive hearing protection, and can reportedly gauge head trauma suffered by the wearer.
The new helmet is just part of a six-part system, Soldier Protection Systems, which aims to protect a soldier's eyes, head, torso, and pelvic region. IHPS was recently worn by paratroopers during an airborne exercise, and the Army will issue 7,000 of the helmets to soldiers across the Army in 2018.
The Integrated Head Protection System (IHPS). Source: US Army photo
Helmets have come a long way since the M1917 doughboy helmet of World War I, and may now arguably be catching up to the lethality of the weapons used in modern war.
Nevertheless, the US military must remained prepared to meet the threat of both a conventional conflict with an opposing nation, as well be equipped to fight non-state actors, including global terrorism groups that almost exclusively rely on asymmetric tactics. And as the last 17 years have demonstrated, this means better headgear must be coupled with new ways to defeat IEDs – as well as a better understanding of the traumatic brain injuries that result from these explosives.
We hope you’ve enjoyed this series on the history of US combat helmets and head injuries …
If you’d like to learn more about new ballistic helmet research conducted by the Army and the Marine Corps, read this blog. For information on the latest in testing methods for evaluating the protection offered by tactical helmets, check this one out. And be sure to catch up on the previous installments in this series: