WW2: Did US marines and soldiers really go into action with unbuckled helmet chin straps?

Question

(Note: links go to realistically portrayed scenes of WW2 combat.)

I am watching Youtube clips of WW2 miniseries, like The Pacific and Band of Brothers.

Based on a non-scientific survey of these miniseries, it looks like US marines and soldiers buckle their chin straps in landing craft or aircraft - and unbuckle them once they hit the landing zone. Like here or here or here or here. The chin strap will either dangle photogenically, or the helmet will appear to have had its strap completely removed.

What happens when you are in a war zone with your chin strap unbuckled? You lose your helmet. Losing your helmet in a war zone is a Bad Thing. (Unless you are a lead actor and will survive for dramaturgical reasons.)

Now, the advantages of having your chin strap buckled appear obvious to me. So I'd assume they would be as obvious to US marines or soldiers - and to actors playing them. (They certainly did to my drill instructor twenty years ago, who did not want to see us with dangling straps.) So I have to assume that someone told the actors to unbuckle the chin straps.

Did WW2 marines and soldiers actually go into action with their chin straps unbuckled? If so, what was the reason? If not, were actors in these miniseries actively told to unbuckle their straps? If so, what was the reason for that?

(Incidentally, History.SE suggests that this question may already have my answer: Did the Celts really go into battle naked? Umm... not quite.)

Answer 1

Yes, they did. Not all, but a very many, especially the more veteran soldiers. I don't have time to get sources together, but will when I do. Reasons were varied.

Some believed that being close to over-pressure events (artillery, etc) could cause a head injury with the large helmet being force up and the tough leather strap breaking the neck. This was supported by more than one army regiment actually giving written orders to their men to not buckle up.

^{From usmilitariaforum.com}

^{From usmilitariaforum.com}

Others believed that an enemy soldier could sneak up behind, in hand-to-hand combat, and use the leverage of the helmets front lip with the strap and break the neck using the back edge.

Having worn a 'steel pot' in my earliest army time, I will say the number one thing about it, by far is it is heavier than any other hat I ever wore on my head. When running, whether or not the chin strap was properly fastened, that pot would rock forward and back and side to side, taking my head with it, such that I was forced to use a hand to keep it in place regardless of the strap! Now, considering that the original strap was just a strip of some material that was itchy and scratchy, I can easily understand why soldiers wouldn't want it done up. Even the later straps, like I used, made of nylon and cotton webbing, would be quite the sweat magnet and end up very rough.

Finally, one of the biggest reasons, directly related to the weight (did I say it is VERY heavy?) was that a soldier would want to remove it whenever and wherever possible, as soon as possible. Figuring that soldiers, even those in the front lines, spend most of their time not actually fighting, but standing, sitting, waiting, marching, being trucked here and there, would tire of constantly doing and undoing the pain in the ass d-ring connections.

Answer 2

Yes, many did. An image search reveals plenty of examples. Although I've found few with the straps hanging, most have the straps secured tightly behind the helmet.

BAR Gunner, 1st Marine Division, Wana Ridge, Okinawa 1945

Three reasons are cited (and one which is my own speculation).

In close combat, an enemy can grab the visor.

The idea here is an enemy gets you from behind, grabs the visor, and pulls your head back exposing the throat and belly. Probably more foxhole fantasy than reality.

An explosive concussion can blow your helmet off, snapping your neck.

That might seem ridiculous, but it seems plausible enough that the US Army redesigned the chin strap to release at a certain pressure, the T-1 pressure buckle.

The helmet can block vision or get snagged.

This one is my own speculation. If the helmet gets snagged, I'd rather it fell off than get snagged with it. If the helmet falls over my eyes, I want to get rid of it quick.

A buckled M1 helmet is not terribly comfortable.

I think this is the real reason and all the rest are justifications. It weighs almost 3 pounds. The straps have none of the benefit of modern materials, they'll be leather and canvas. Rough and inflexible. The nape strap can hold the helmet on well enough.

Source

You'll see modern US soldiers almost universally with their chin strap on. The current US Army Advanced Combat Helmet is a little heavier, but it benefits from modern ergonomics and materials. We also now have lots and lots of data about where and how soldiers get wounded, and modern combat involves a lot more shrapnel.

Soldiering is long periods of boredom punctuated by moments of extreme violence... or if you're far enough behind the lines, just more boredom. In those long periods of boredom you're hauling around all this very heavy and uncomfortable equipment. Many soldiers will make modifications which might reduce their combat effectiveness in order to be more comfortable in the hours, days, weeks, and months between combat.

Whether the justifications are valid doesn't matter, if the soldiers believed them that's what matters.

Sources:

• The Guardian, Stage And Screen, Notes & Queries
• BAR Gallery