Combat Helmet Continues to Evolve, Step by Step


The results of a year-long study to build the best helmet to withstand blunt trauma have been unveiled by the Pentagon, revealing the US Army’s current Advanced Combat Helmet (ACH) continues to provide the best protection for soldiers.

The main objectives of the study, funded by the U.S. Army and the Joint IED Defeat Organization (JIEDDO) and undertaken by Lawrence Livermore National Laboratory, were to gain insight on how the helmet pads protect against impact-induced traumatic brain injury (TBI), and find better ways to protect soldiers.
“There are three things we’re trying to provide our soldiers,” said Brigadier General Peter Fuller, program executive officer at PEO Soldier, “protection from blasts, such as the blast wave experienced in the body; blunt or impact trauma when the body is slammed up against the interior of a vehicle following an IED explosion; and ballistics — being hit by bullets and fragments.”

Program Executive Office Soldier was created by the Army with one primary purpose: to develop the best equipment and field it as quickly as possible so Soldiers remain second to none in missions that span the full spectrum of military operations.
“We were asked to compare the impact response of NFL football pad systems and pad materials with the Army pad systems,” said William Moss, co-author of the report at Lawrence Livermore National Laboratory, and directed by the Joint IED Defeat Organization.

Because blast-induced traumatic brain injury is one of the most common military injuries in Afghanistan and little is known about how personal protective equipment can deflect the impact of an IED, Army Vice Chief of Staff General Peter Chiarelli directed JIEDDO to review the mitigation capabilities of the ACH against impact injuries in 2009.

The Army pad systems tested were the Team Wendy pads, in use since 2005, and the Oregon Aero pads, prior to that date.

The key findings showed that neither the NFL systems (Riddell and Xenith) nor Oregon Aero outperformed the Team Wendy pads in militarily-relevant impact scenarios in ACH helmets (impact speeds from 10 to 20 feet per second).
“We found that for a small increase in pad thickness, there was an enormous effect on impact mitigation,” Moss said. The current pad is three-quarters of an inch thick. The study indicated this improved effect occurred by adding one-eighth to one-quarter of an inch of foam.

This brought up another problem, though. By adding thicker pads, the helmet had to increase in size which meant an increase in weight, something no soldier wants.
“Helmets have to let the soldier do their job. They have to shoot, move, communicate, and concentrate in order to remain lethal and be able to operate in any environment,” said Colonel Bill Cole, project manager for Soldier Protection and Individual Equipment at Program Executive Office Soldier, Fort Belvoir, Virginia.
“Soldiers are very sensitive to weight, especially on their head, and that’s what we see in feedback on all of our equipment, ‘Hey, we love the fact that it saves lives, but anything to reduce weight, please do it,'” Cole said.

Bigger helmets can often be unstable, especially when wearing night vision goggles off the front end of the helmet.

Another result of the study showed that every head shape and size was different. This meant that helmets need to be fitted better, something that Natick Soldier Research, Development and Engineering Center in Natick, Massachusetts, is developing.
“Soldiers should receive the proper size helmet with the proper size pads to accommodate those differences in head shapes,” said Mike Codega, technological program manager at Natick.
“The solution is a holistically new helmet that incorporates this new knowledge about helmet pads with one of our new capabilities, a laser-scanning technology that will allow us to laser scan a great population to understand the differences in head shape,” Codega said.

For the past six months, though, the Army has been able to offer a one-inch-thick pad to give better fit in the front and back or on the sides for slightly shorter or narrower heads.
“The ability to get a good-fitting helmet is crucial for the soldier to be able to do their job,” Cole said.

He pointed out the pronounced contour around the ear.
“This is needed for hearing, but it’s rather difficult to manufacture in that contour and still maintain the ballistic capabilities we want in our helmets to make sure they can stop the bullets and fragments the way they’re supposed to.
“So we’re toying with new shapes where we can smooth out that contour and possibly shape the interior of the helmet shell differently, so we can incorporate larger pads if needed,” Cole said.

Cole also said that proper fit procedures are being re-emphasized.
“We have calipers and tape and manuals to make sure soldiers get the right-size helmet for their head, and we’re also putting the word out in the field that any soldiers that might have bought commercial pads that are less than three-quarters of an inch should be taken out and thrown away.
“You need at least three-quarters of an inch to get good protection. If your head is shaped so you need to use the one-inch pad to get proper fit, that’s even better,” Cole said.
“There are three things we are doing,” Fuller said. “Because we’ll never stop improving the protective gear soldiers wear, we’re getting ready to put out a solicitation for a new helmet pad.
“And we’re putting helmet sensors, called Generation 2, in our helmets, to help us gather more data to feed into the medical community as they record the G forces that are a part of the soldier’s experience during blunt trauma and blast events. These will be deployed later this summer with six brigades,” Fuller said.

Finally, last summer, soldiers were given a new enhanced combat helmet, a co-effort with the Marine Corps, which increased ballistic protection. This new, thicker shell is composed of high molecular-weight polyethylene, as opposed to the Kevlar in the ACH
“The number-one issue we had was ‘don’t increase ballistic protection and increase the weight at the same time.’ So we came in with increased protection at the same weight of our current helmet,” Fuller said.

Protective gear is a complex problem, Fuller said.
“If we thought a larger helmet would immediately protect you, we’d go do it. But I want to reinforce that we’re focusing on our soldiers. We’re trying to figure out what is going on, how do we help them, how do we mitigate,” he said.

Understanding the interface between the physics of blunt protection and the human body, specifically the head, he said, is what the Army is pursuing.
“I don’t understand what’s happening inside your head, but if I can at least capture the data of what happened to your helmet which was attached to your head, during a traumatic event, whether it’s blunt, blast or ballistic, we can then provide this information back to the medical community so they can understand it,” Fuller said.