International Distress Signalling Protocols and Attracting Attention.
by Survival Expert James Mandeville ©2020
This article is primarily for:
The Military, Outdoor and Extreme Sports Enthusiast and General Interest.- RETURN TO ARTICLES LIST -
International distress signalling protocolsUsing sound or light to signal for help and to reply to survivors. Standing up and raising arms over the head means: "I want to be picked up."
Lie down on ground with arms stretched over the head means: "Require medical assistance."
Military ground–to–air signsRemember that to be seen from an aircraft letters and symbols should be at least 5.5 metres (18 feet) tall and letters have to be in reasonable proportion or they will look meaningless from the air.
International ground–to–air signals for civilian rescue situationsShore–to–ship signalsSome illustrations courtesy of the US Coastguard.Attracting attention from the seaSurface–to–air signals Note: Use international code or signals by means of lights or flags or laying out the symbol on the deck or ground with objects that have a high contrast to the background.
Air–to–surface repliesAir–to–surface direction signalsSurface–to–air repliesSearch and rescue unit repliesMeans of attracting attention from landIf you are in trouble the classic advice is to stay put and wait for rescue unless that is not a realistic option. Try to leave some ground marker or message behind to indicate your direction of travel if you have to keep on the move. If you do stay put, you should immediately start preparations for attracting attention. There are many ways you can signal would be rescuers so they can find you more easily. Start thinking about what equipment you have that could be used for signalling. Suitable items are mirrors (even a polished belt buckle has been used as a successful signalling device), a torch, a camera flash, a whistle (you can make a loud noise by placing a leaf of broad grass between your thumbs to act as a reed and blowing). Remember that coloured clothing spread out in a clearing, a silvered or orange survival blanket, etc., are readily visible in nature because these things look out of place. If you have to shelter because of the weather mark your position with something brightly coloured so rescuers don't just walk right past you or fly over you.
Signalling equipment designed for the purpose includes a StarFlash mirror (see photo below), battery operated laser strobes (photo right: Rescue Light by Greatland Laser) and signal flares.
Even if you have any of the above aids, you should prepare a signal fire as smoke can attract attention from a great distance. Start preparing three signal fires immediately but only light one fire so you have a quick means of lighting the others, unless you have vehicle fuel, liquid fuel from a camping stove etc., and can start a fire immediately.
The internationally recognized rescue signal is three fires equally spaced in a line or in a triangle. If possible, separate each fire by at least 15 metres (50 feet). Nowadays most search aircraft are fitted with thermal imaging cameras so it is a good idea to keep a large fire going constantly at night as the thermal imaging camera will detect the large heat source. Waiting until you hear a plane before building your fires is pointless, because before you get them burning the aircraft will be long gone. Unless you have a source of ignition (matches, lighter, etc.) and lots of dry kindling, light your fire as soon as possible and keep it burning. If you hear a plane add fuel to your fire. The rule is that white smoke or a blazing fire can be seen better at night and black smoke in the daytime (unless the sky is very dark, then any smoke will be seen), so you need to prepare this fuel and have it to hand so you can quickly place it on your fire and make smoke. Damp grasses and pine branches with pine needles make white smoke; even dropping a little water on the fire will have the same effect but don't put the fire out!
To make dense black smoke the best fuels are car tyres, foam padding from seats, oily rags, electrical insulation, polythene or plastic. See what you can spare, bearing in mind the rescue aircraft may not spot you on the first attempt. Gather lots of fire making materials as well as green vegetation so everything is ready. You will have to find a clearing or make one to allow a wider angle of view for rescue aircraft if you are in heavy forest. If you hear a plane at night, light all three fires quickly with small dry wood or dead leaves to produce as much light and flame as possible. If a plane is passing over in daylight cover the fires with vegetation to produce heavy white smoke; use some type of signalling device such as a white T–shirt and wave frantically. If a search and rescue plane locates you the pilot will usually do at least one direct flyover at low altitude and "wave" you with his wings. Use the signalling methods detailed previously to communicate with the pilot.
If a plane passes close enough at night, you can use a torch to signal the international distress Morse Code of SOS (three short flashes, three long flashes and three short flashes.) Pen flares and pocket signal strobes are best for night–time signalling but a torch or strobe is not so likely to be seen by a pilot unless he/she is specifically searching for you. Nothing beats a signal mirror with an aiming screen for daytime signalling of aircraft. This is
very accurate for flashing a light into the pilot's eye from many miles away. If you have no signal mirror then find anything with high reflectivity and put a hole in the centre of it so you can see through it. To aim it, extend an arm in front of you, hold up two fingers in a peace sign configuration and box the aircraft inside these fingers. With your other hand, move the reflective device up to your eye and sight through the hole finding the aircraft in between your two fingers. Keeping your eye on the plane, move the reflective device around until you see a flash of light cross over your peace sign. You have just flashed the aircraft. Make sure not to hold the signal static on the plane, instead flash it back and forth. Once you receive a positive signal from the plane that you have been seen, stop signalling so you do not confuse the pilot. Signal mirrors can also be effective on hazy days.
Always leave a direction marker pointing in the direction you are going if you decide to leave your base camp or crash site. If rescuers reach your camp or crash site they will at least know in which general direction you are headed. You should also mark your route as you travel, just in case you decide to return to your base. Make a trail by snapping small branches and breaking over small plants so they will be visible on your return trip. If you use this technique, always break the plant so the underside of the leaf will be visible on your return. The bottom side of a leaf will contrast better against the forest than the top side and will be notably out of place when you're looking for your track. Take note of landmarks, such as, a specific fallen tree, a noticeable boulder, the overall typography of the ground, anything that will help you find your way back. Periodically turn and study the way you have just come because everything can look completely different on the return journey.
People can get lost amazingly quickly in unknown territory. Staying calm, assessing your situation and being decisive will go a long way when it comes to saving your own life. If you are the survivor of a plane crash you have an excuse for not being prepared, but if you just set off into the wide blue yonder with no preparation you are asking for trouble — that day trip can turn into a days-long nightmare and this happens more often than one would think. Never go exploring new terrain without a map and compass and signalling devices in your possession. And if you don't carry a map with you, at least make sure you observe natural features such as surrounding roads, rivers and adverse terrain so you have a good idea of your location.
Morse CodeFlag SemaphoreFlag semaphore is the telegraphy system conveying information at a distance by means of visual signals with hand–held flags, rods, disks, paddles, or occasionally bare or gloved hands. Information is encoded by the position of the flags; it is read when the flag is in a fixed position. It is still used at sea and is acceptable for emergency communication in daylight or, using lighted wands instead of flags, at night.