Although I I write this, the news is telling of another fatal fire fighting helicopter crash, people do survive crashes all the time. As a career National Park Service employee, I took several crash survival courses. In general, no not wear synthetics, especially underwear - a nomex flight suit and gloves are real good items. I remember a very vivid video, debriefing a heli crash survivor at Yosemite. This person mentioned having absolutely nothing for survival gear after the crash. Since getting out of the bird can often be a problem, and you may never have the opportunity to grab your stuff, bulky survival packs are out - this would be a perfect application for Doug's Altiod tin. Most military folks fly wearing a survival vest that, even loaded, is fairly svelte.<br><br>There are crashes and there are CRASHES. I have flown in a fairly wide variety of both military and civilian choppers over the years - I never declined a flight that was in the line of business, but I never took a frivolous or unnecessary flight either.<br><br>