Helmet straps
 

I have noticed that very few war movies feature soldiers who actually use their helmet chin-straps on a regular basis. Is this a Hollywoodism, or does the weight of the helmet itself generally keep itself in place?

It's got to be a Hollywoodism. The straps are there for a reason.

Mostly a Hollywoodism. You occasionally see pictures of soldiers from Vietnam with their helmet straps undone, propbably because of A: poor discipline, and B: those straps get bloody uncomfortable when you're sweating. However, the straps are there for a reason and today proper wear of PPE is very strictly enforced. When I was in Afghanistan I saw people getting chewed out all the time for stuff like that. Dress and deportment stuff does slide a little overseas, I rarely if ever actually wore my hat on camp, but PPE gets taken seriously because something like buckling your helmet strap can and will save your life.

I'm not sure it's all Hollywood, if you look at archival footage from WWII to Vietnam, soldiers just let their straps dangle. The traditional answer was that soldiers didn't do it because supposedly, there was a danger that the concussion from a nearby explosion could break their necks. I think it's all a myth though because A) all the footage of our troops in Iraq and Afghanistan have their helmets securely strapped on, and it's not like explosions are no longer a danger on a modern battlefield, and B) you'd think that any concussion that can move a helmet so quickly it'd snap someone's neck would just outright kill him anyway.

I think it's just an American thing. All the old pictures of Bundewehr troops with the old M1 steel pot that I've seen had them strapped on, and all of the pictures of my dad from his ROC army days had him with an M1 strapped on too.

I'm not sure it's necessarily a discipline thing. If you look at the link below, you've got a SSgt with his helmet (and flak jacket) undone, in front of a captain and a four star general no less. (It's in the caption.)

http://www.latinamericanstudies.org/...grenada-10.jpg

Maybe it's a generational thing? That SSgt looks like he's been around a while.

Maybe it's becauces Grenada wasn't a real war and nobody gave a shit.