This Old Helmet, Episode 1

November 4th, 2006

Introduction

The PASGT (Personal Armor System Ground Troops) helmet (“Kevlar”) has been in the US military inventory since the early 1980s. It represents a significant improvement over the steel helmet, which had served since the early 1940s.

The PASGT has provided significantly improved protection against fragmentation, but was not considered to provide significant ballistic protection.

The helmet could actually prevent penetration by fragments with as much energy as a handgun round at point-blank range. But the helmet would deform over two inches in the process, usually inflicting severe or fatal blunt trauma injury to the head. This lack of blunt trauma protection also meant the helmet could not provide any protection in automotive accidents.

In the course of developing improved helmets over the last few years, the old web suspension system, little changed from the steel helmets of the 1950s, was replaced by special cushioned pads that provided superior blunt trauma protection, and improved comfort.

These pads are part of the Advanced Combat Helmet (ACH), now in production. At the same time, various companies have developed update kits for the current PASGT. This brings the helmet up to the same level of protection as the new ACH.

Future articles will feature some of these upgrade kits. But whether you have a new ACH, or upgraded PASGT, the key to maximum protection and comfort is in fitting the pads to the individual wearer. This takes a little bit of time, but it’s an investment in your safety and comfort.

Fitting the pads

Whether you have an upgraded PASGT helmet, or a brand-new ACH helmet, fitting of the foam pads is the key to both increased protection, and increased comfort. It is also something that should not be rushed, because you are customizing the fit for yourself alone. A new pair of boots requires breaking in. These new helmets require time to find the best pad layout. Plan to spend at least two or three hours of “quality time” with your helmet, and you’ll be paid back with greater safety and comfort.

First, if the chin/nape strap is already attached, take it off. Leave the plastic H-buckles on, just take off the cloth strap. It’s the last item that needs fitting, and only gets in the way of working with the pads.

Next, a quick word about pad thickness. For the Advanced Combat Helmet, there are two different thicknesses of pads: number 6 (thinner), and number 8 (thicker). Both provide equal protection. The only difference is to assure the best possible fit with the size of helmet you’re working with. The number 6 pad is considered “standard”, while the number 8 is used for a better fit when the helmet is too large.

Oregon Aero, manufacturer of one of the upgrade kits, also makes a thinner number 4 pad. Again, it should be used only if there are problems in fitting. The approximate thickness of the pads is:
· #4: .07 inch
· #6: .09 inch
· #8: 1.1 inch

The round pad goes into the bottom of the helmet first. Try to get it centered as well as possible. Then the two “trapezoid” pads go in the front and rear of the helmet. The narrow part should be touching the round pad.

With those three pads in place, we’re left with the four oblong or rectangular pads. Some documentation mentions the pads may be oval, but I’ve never seen any. It’s these four pads that are the key to a comfortable fit, and the overall increased safety of the helmet. Adjusting these four pads takes up most of your time, but it’s also where the biggest benefits come from.

Most illustrations show the four pads arranged horizontally around the rim of the helmet. That configuration makes for the tightest fit, but that may not always be best for you.

The secret to a good fit is that these pads can be arranged horizontally, vertically, or at an angle. They can also be placed closer to, or further away, from the rim. Different pad orientation provides different fits, and one will be right for you. This is also where most experimentation will be done. The closer the pads are to the rim of the helmet, the tighter the fit. The closer to the center, the looser the fit is.

The most important thing to remember is to have the pad either cover the mounting hardware, like the A-nuts that hold the plastic buckles, or are close enough to these protruding items that they won’t be able to contact your head in a severe impact.

Take your best guess at pad orientation, and then place the helmet on your head. There should only be a slight amount of pressure, usually around the temples, when you put it on. Slap the top of the helmet to make sure it’s fully seated. If you’re still feeling pressure, the two front rectangular pads may need to be moved a bit.

Once you have a reasonably good fit, wear the helmet for about two hours to “settle” the foam pads. This is the most important part of a comfortable fit.

You should be able to move your head around without feeling any movement of the helmet. If you look down at the floor, the helmet should not fall off. The “lighter” foam in the pads is for comfort, and will take a slight “set”. It’s the heavy-duty foam in the base of the pad that provides the real trauma protection. That, in turn, increases the helmet’s ballistic protection.

After about two hours of continuous wear, if the helmet still feels good on your head, the fitting process is almost over. Now reattach the chin/nape strap, making sure none of the straps are twisted. Adjust the straps for a good fit, and check the final results in a mirror. The helmet should not be tilted either left or right, or forward or backward. There are several FMs that show how the helmet should look when worn properly.

This is more effort at fitting than with the old suspension system, where you adjusted the inner loop of the suspension straps, and you were done. But the payoff in comfort and safety is worth the extra work. As a test, I wore a properly-fitted ACH helmet for six hours straight with no discomfort. In the “good old days”, I could never wear my steel pot for that long without coming up with some excuse for taking it off, with the hope of finding another excuse for not putting it back on.

It’s your head. Invest enough time to keep it safe and happy by fitting it properly.

Entry Filed under: General, Troop support, Troop Tech, Hobbit Hole Skunk Works