While leading new recruits on a night navigation exercise a few years back, one of the troops in my section fell through the ice while crossing a frozen river. The water was not deep (she only went in up to her arm pits) but it was end Janurary in Wairwright Alberta. The temp was about -40 degrees celcious. She basically fought her way to solid ground which was no small task in snowshoes and imediately started to go down with hypothermia. When the temp is so low things can go south very quick in this type of cold. We usually have a safety vehicle roaming around between the patrols but at the time this happened I could not reach them on the radio(built by the lowest bidder) With my handy little PSK which I never am without, we managed to get a fire going fast(about fifteen minutes), and a makeshift shelter using a space blanket. We got her out of her wet clothes, which by this time she was unable to do by herself, and helped her put on whatever we had extra for clothing. At this point she had actually stopped shivering, which is not a good sign. Once in dry clothes, and with a roaring fire she soon started coming round and told me that she could feel her feet again. Normally, a fire is not an option due to the tactical side of Army stuff, but for a simple training exercise safety is the biggest concern. I was dumbfounded at how many soldiers did not have a single match on their possesion when this happened. In fact, besides my PSK, the only people that had a means to light fire were the smokers. Once the wet trooper was warmed and starting to dry, It was actually a blast sitting down and telling stories next to the fire. We kept it going long enough to semi dry her boots as best we could(no spares for these) and then headed back to the patrol base. From then on, any person in my section was made to carry a small PSK while on winter ops, whether they liked it or not.