ice; this lowers your body temperature and thus reduces endurance. One way you can melt snow or ice for drinking water is to put ice or snow in a plastic water bag and place it between the outer layers of your clothing.
If your fuel supply permits, it is better to drink hot water in cold climates. Hot liquids area rapid and effective source of internal warmth.
There are more than 50 named deserts in the World. Deserts cover nearly one-fifth of the earth's land surface. Therefore, the aircrewman must have a good knowledge of desert survival.
Deserts have extreme temperatures; hot days and cool nights are common. You may think of a desert as always being hot and dry. However, in winter months, the desert can become a freezing nightmare.
Lack of water and exposure to sun and heat are the big hazards to health in the desert. One to five percent dehydration will make you lose your appetite, become sleepy and nauseated, and begin to vomit. As dehydration goes up to 10 percent, dizziness results. You will have headaches, difficulty in breathing, tingling of the legs and arms caused by poor circulation, indistinct speech, and, finally, an inability to walk. Still, 10 percent dehydration generally causes no permanent ill effects. When dehydration exceeds 10 percent, you will become delirious, spastic, almost deaf, and barely able to see. The skin shrivels and becomes numb. At temperatures above 90F, dehydration over 15 percent is generally fatal. At 85 and less, the body can stand up to 25 percent dehydration. Dehydration is quickly cured by water - in fact, only water can cure it.
When you are dehydrated, you don't have to worry about how much water you drink or how quickly you drink it if the water is warm or cool. Cold water, though, will upset the stomach.
Table 5-1 shows the number of days you can normally expect to survive on a given amount of water, according to temperature and whether you rest or walk at night until you are exhausted.
Aside from a lack of water, exposure to the sun is the foremost desert ailment. Stay under cover as much as possible. If you must be out in the sun, keep as much of your body covered as possible. Roll down your sleeves, button your collar and turn it up around your neck, keep your head covered, and, if possible, cover your face also. Tuck the legs of your pants into your socks and keep your shoes on. On any area of your body that is not covered with clothing, use a sunburn ointment. It is better to use it as a preventive than as a cure. Wear a cloth neckpiece to cover the back of your neck from the sun. If you have no hat, make a headpiece like that worn by the Arabs, as shown in figure 5-40. You can also adapt your pilot chute as a parasol for use in the desert.
Exposure to desert heat is dangerous. It may cause three different types of heat collapse - heat stroke, heat exhaustion, and heat cramps. Another desert danger is sun glare. Glare is extremely painful. You can avoid it easily by taking the proper precautions. Keep your eyes protected from the glare of the sun by darkening the bridge of the nose and the area beneath the
Table 5-1. - Survival Potential as Determined by the Amount of Water, Temperature, and Activity