If you think that your vehicle is going to be easily spotted by search and rescue personnel, chances are you are wrong. Imagine standing in the middle of a field and trying to spot an ant in the grass. In most cases, this is what it will be like for search and rescue personnel if they do not have a detailed plan of where you were heading and are not able to be on the lookout for specific signalling or marking from the air or high ground.
There are many forms of signalling and we will try to cover the majority of the most popular ones below. Depending on your location, some may be more successful than others and you should always have more than one method if signalling or marking planned.
Signaling Mirror – Cheap and effective on bright sunny days, when used correctly, the signal mirror can be seen from a great distance and alert search and rescue personnel of your location. For information on how to use a signaling mirror, check this page. You should not wait until you need to use a signaling mirror to try it for the first time. On a sunny day, a mirror is your best signaling device. If you don’t have a mirror, polish a metal canteen cup, your belt buckle, or a similar object that will reflect the sun’s rays. Practice using a mirror or shiny object for signaling now; do not wait until you need it. If you have an MK-3 signal mirror, follow the instructions on its back
Strobe Light / Flashlight – At night you can use a flashlight or a strobe light to send an SOS to an aircraft. Some strobe lights flash 60 times per minute. Some strobe lights have infrared covers and lenses.
Emergency Flares / Pen Flares – Flares are a good way to draw attention to your location at night, but they pose a fire hazard and should only be used when safe to do so.
Whistle – Whistles provide an excellent way for close up signaling. In some documented cases, they have been heard up to 1.6 kilometers away. Manufactured whistles have more range than a human whistle.
Air Horn – Air horns only last so long. While they can be used to draw attention to your area, you need to consider how long they will last versus another item such as a whistle
Bright Colored Material – During daylight you can use a bright colored panel of fabric such as the U.S. Military VS-17 panel to signal. Place the orange side up as it is easier to see from the air than the violet side. Flashing the panel will make it easier for the aircrew to spot. VS-17 panels are available online through many of the military surplus stores. If you do not have a VS-17 panel, You can use any bright orange or violet cloth.
Fire – During darkness, fire is the most effective visual means for signaling. Build three fires in a triangle (the international distress signal) or in a straight line with about 25 meters between the fires. Build them as soon as time and the situation permit and protect them until you need them. If you are alone, maintaining three fires may be difficult. If so, maintain one signal fire.
When constructing signal fires, consider your geographic location. If in a jungle, find a natural clearing or the edge of a stream where you can build fires that the jungle foliage will not hide. You may even have to clear an area. If in a snow-covered area, you may have to clear the ground of snow or make a platform on which to build the fire so that melting snow will not extinguish it.
A burning tree (tree torch) is another way to attract attention. You can set pitch-bearing trees afire, even when green. You can get other types of trees to burn by placing dry wood in the lower branches and igniting it so that the flames flare up and ignite the foliage. Before the primary tree is consumed, cut and add more small green trees to the fire to produce more smoke. Always select an isolated tree so that you do not start a forest fire and endanger yourself.
Smoke – During daylight, build a smoke generator and use smoke to gain attention. The international distress signal is three columns of smoke. Try to create a color of smoke that contrasts with the background; dark smoke against a light background and vice versa. If you practically smother a large fire with green leaves, moss, or a little water, the fire will produce white smoke. If you add rubber or oil-soaked rags to a fire, you will get black smoke.
In a desert environment, smoke hangs close to the ground, but a pilot can spot it in open desert terrain.
Smoke signals are effective only on comparatively calm, clear days. High winds, rain, or snow disperse smoke, lessening its chances of being seen.
Solar Blanket – The solar blanket can be used in a similar fashion to the bright colored material. The solar blanket will have a shiny side which will reflect sunlight and the other side is typically red or orange. Both sides can be used for marking and signalling depending on the situation and environment.
Laser Pointer – Targeting pointers and many commercial types of laser presentation pointers are highly visible. Be careful to not direct the laser beam in the cockpit of the aircraft.
Clothing – Spreading clothing on the ground or in the top of a tree is another way to signal. Select articles whose color will contrast with the natural surroundings. Arrange them in a large geometric pattern to make them more likely to attract attention.
Natural Material – If you lack other means, you can use natural materials to form a symbol or message that can be seen from the air. Build mounds that cast shadows; you can use brush, foliage of any type, rocks, or snow blocks. In snow-covered areas, tramp the snow to form letters or symbols and fill the depression with contrasting material (twigs or branches). In sand, use boulders, vegetation, or seaweed to form a symbol or message. In brush-covered areas, cut out patterns in the vegetation or sear the ground. In tundra, dig trenches or turn the sod upside down. In any terrain, use contrasting materials that will make the symbols visible to the aircrews. Orient the signal in a northsouth fashion to attain the maximum benefit of the sun’s shadow for contrast and recognition.