After you've put to use all the techniques for building a shelter and a fire, it's time to think about signaling. You must consider signaling your third priority of life. There are two goals here:
To let someone know where you are
To let someone know you need help
The main rule to keep in mind regarding signaling is that a good signal is anything that makes you bigger than you are and attracts attention to your situation.
Signaling, like everything else in survival, is not a spur-of-the-moment ordeal. You must prepare for it. It's impossible to know when help will come within sight or hearing. Prepare for two types of signaling: ground-to-air and ground-to-ground.
One of the first steps is to locate a clearing where signaling efforts are easily visible. If you are not in a clearing when you become lost, move to one, then stay put until a search and rescue team finds you.
Your signaling process is dictated, to some extent, by geography and the time of year. If you are in the mountains, it is likely that signaling at night will be a waste of time. Because of hazardous flying conditions, most search flights end at sundown; treacherous terrain may rule out ground searches as well. In the desert or on the plains, however, searches often go on around the clock.
There is a new set of international symbols that has been developed by a committee on international civil aviation. Keep in mind that if the symbols are being used to attract attention, they need to be from 30 to 50 feet in length and 3 to 4 feet wide. If they are being used in response to a question asked by a pilot in the air via a PA system, they need only be large enough to convey your message. These symbols can be tramped in snow or sand, or constructed out of ground litter, debris or any available material.
The first symbol is a “V”. This means require assistance. The second symbol is an “X”. This means require medical assistance. “N” means no. “Y” means yes. An arrow pointing in a direction means proceeding in this direction. These do not replace any of the military symbols—this is strictly for civil aviation.
Fire is a powerful signaling tool, and one that requires advance preparation. To create the V symbol, (to signal that you require assistance) prepare three fire bases in a triangle 30 to 50 feet apart. The fire at the apex of your V should be your camp fire, which will be burning at all times. The fire bases on the points of the V will be prepared, but not always burning. When a search aircraft (a single engine aircraft or a helicopter) enters your area, light your other two fire bases. This will give you a triangle of fire, which will distinguish your plea for help from other fires that may be in the vicinity (of which you are unaware).
The same method applies to smoking fires. Build your fire bases on the points, with extremely dry tinder on the bottom. On top of that, put lots of dry kindling, and on top of that pile green vegetation. When a search aircraft enters your area, pile green material on top of your existing fire, and torch off your other two fire bases. This will give you the triangle of smoke.
The very best type of ground-to-air signal during sunlit hours is the glass G.I. type signal mirror. This type of mirror will generate 5 to 7 million candlepower of light in bright sunshine, and can be seen for 20 to 25 miles. This type of power will never be generated by the metal mirror. The G.I. type mirror is available at most surplus stores. Read the directions on the back of the mirror and practice before venturing out.