The unfortunate fact of the matter is it seems very few, if any, seats in the military have any sort of comfort in mind
FLY_USMC's statement pretty much hits it center mass. With few exceptions, ergonomics (other the panel) is largely overlooked. Sikorsky has the best of the several models of helicopters I've flown, but even the 60' cockpit designers never planned on full tactical vest with front and back ballistic plates.
My 85-million-dollar "new" Chinook is built around the exact same seats it had 20 years ago, along with the same Huey seat belts. No matter how you manipulate the 4 different adjustments on the seat, you're still bent at a 90 degree angle and hunched forward. I look like a gypsy when I get in the cockpit; towel rolled up for lower lumbar support, an inflatable seat cushion to allow me to tollerate any flight over 3 hours. Even worse, our gunners are using folding metal chairs in back instead of the airframe integral seats because the engineers didn't have the fore thought to see if they could actually reach the guns from their seats, and standing hunched over isn't realistic for multi-hour missions. I'm surrounded by amazing technology, but amazed how any sort of cockpit comfort was overlooked. The civilian helicopters I've flown were very comfortable without any sort of flight gear, albeit I never spent more than a couple hours in the seat. Because heaven for bid, if a company bought an S-76 and the pilots said the seats sucked, it would be returned to the manufacturer for a refund...DOD hasn't figured out that concept.
In the MH-47's case, it was specfically designed for LONG range penetration which now has developed into nightly missions of at least 10 hours in the seat. 15 hours isn't unheard of. Depending on the age of the pilot, it's not uncommon to have to be helped out of the seat at the end of the night. Most of us also have standing monthly chiropractic appointments.
As far as added stress of wearing NVG's. After about 1,400 hrs of NVG flying, I haven't experienced any aches or pains I can attribute to them. I think they key is to properly counterweight them on the back of the helmet. I have over recent years started doing light neck raises as part of my exercise, whether it works or not I don't know, but it doesn't hurt.
