I don't think I would bother with a snorkel, even if there were a likelihood that I would wind up in the water. I have bobbed in the water for longish periods (the longest was about 45 minutes) at the end of a dive, trying to hook up with the boat and it is better to attain maximum buoyancy, inflating the BC, and dropping the weight belt, to get up out of the water as high as possible. I never used my snorkel at all in any of these situations.<br><br>In a survival situation, you should strive to get out of the water and up onto or into something in order to combat the hypothermia that will soon be setting in. The single most useful items you can possess is a wetsuit or survival suit if you go into the drink. There is a good history of the utility of wetsuits around the Channel Islands during vessel sinkings. Those who go into the water suited survive, those who don't, don't.<br><br>Snorkels are great for swimming on the surface, but if you are drifting along with the current, they are hardly critical. On the occasion of my 45 minute exposure, the current was taking us to the island, so I relaxed and computed the distance to the closest fresh water source, head comfortably out of the water.<br><br>These situations are much more likley to arise from boat sinkings than airline crashes.