How to Make War reports on a interesting Navy sleep study:
U.S. Navy sleep studies have discovered another thing to look for when selecting sailors for different kinds of duty. The study found that ?short sleepers? (those who typically slept for six hours or less a night), were more alert when they were awakened, but were much less alert after 36 hours without sleep. ?Long sleepers? (those who require nine or more hours a night) took longer to become completely alert when they were awakened, but were much more alert after 36 hours or more of being awake. So if you have to wake up people for an emergency that requires concentration, pick a ?short sleeper.? If you need people who might have to stay awake for long periods, and still be able to function, pick a ?long sleeper.?
It also comments on the popularity of snipers:
One of the least mentioned reasons why snipers are increasingly popular in the U.S. Army and Marines, has to do with logistics. During the Vietnam war it was discovered that 200,000 rifle bullets were fired for each enemy soldier killed. But snipers fired 1.3 bullets for each enemy soldier killed. The 200,000 5.56mm and 7.62mm bullets weigh over four tons. But 1.3 7.62mm sniper bullets weighs a little over an ounce. OK, so snipers fire more bullets in training, but that’s still going to end up with four tons being compared to a few pounds. You cannot have an army of snipers. There are many combat situations (like being ambushed), where a sniper getting off single, well aimed, shots would not be the most effective response. If you are ambushed, you want to put as many bullets on where you think the enemy is, as quickly as possible. But there are many combat situations where a few well placed shots will do a better job than hundreds of less well aimed bullets. Even for the regular troops, single shots are now favored over emptying a 30 round magazine with fully automatic fire. Every bullets counts, especially when you have to move them thousands of miles before you can use them.
(That sounds like an OR finding, doesn’t it?)