How about some form of backstroke? That's how I prefer to surface swim with scuba gear on (inflated BC, not using snorkle or regulator).

To the best of my knowledge, military flotation systems are not designed to help you swim. Swimming requires the output of energy that you need to retain in a survival situation. The PFD provides flotation so that you can keep your head in the air while not expending energy you may need to survive hours or days in the water. Once you inflate a PFD the farthest you should swim is to your liferaft or the helo hoist the Coast Guard drops.

That LPU-10/P looks rather clumsy. I don't see how that design would aid in swimming. You'd still need to deflate the bladders and with them under your arms, they'd seem to interfere with your stroke much more than the collar type PFD's.

The LPU-10/P does look kind of clumsy and I've read some people describing them as "designed by a madman", but its interesting that Mustang's newest tech seems to use similar principles, if not being inspired by the LPU-10/P.

http://www.mustangsurvival.com/lift/

Don't forget the .mil personal floatation system has to fit around ejection seat harnesses, g-suit, etc etc. I think the LPU-10/P was designed to fit in the leftover space.

Good point, not being an ejection sat type I forget about that design criteria -- makes it a bit more of a compromise than other systems.

When I did my qual I noticed that some of the collar types do not play well with helmets. When I inflated one of the PFD's you'd find under your seat on a civilian airliner, it caused a lot of upward pressure on the chin strap. Not as bad with the LPU-32/P.

Backstroke is what they teach divers to do on the surface over long distances. I think its because its partially because the BC/tank combo naturally orients that way, and also because with flippers you have a relatively powerfull backstroke.

Ive been watching videos of people using airline type PFDs, and wow do they look uncomfortable. Seems that they are designed to inflate tight around your neck so that you cant get them off.

When I finished the part of the qual requiring the airline PFD and needed to remove it, the helmet had to come off first and I mostly deflated the PFD in order to take it off. They're probably designed that way so that they won't come off inadvertently if you don't have the strap on correctly. They'll definitely keep you afloat.