Royal Army College

Lesson Overview

Earlier lessons taught a soldier to find their way and stay effective in the field. This lesson covers the opposite case: what a soldier or a small party does when, despite all that, they are lost, stranded, or burdened with a casualty and need help to reach them. It is the skill of being found. In the search-and-rescue work the RKA most often performs, the soldier is usually on the finding side of that equation, so knowing how the lost should make themselves seen is worth having from both directions.

Where there is a working radio, that is the first resort, and the Signals and Field Communication course teaches its use; a clear voice report of who you are, where you are, and what is wrong beats a fire on a hilltop. The skills here are for when the radio is absent, dead, or out of range, which in hard country happens often. Like the map and compass, they are old, simple, reliable, and practised in person under instruction until a soldier can lay out a ground signal or sound a distress call without hesitation.

There is no single magic signal. The party that gets found usually runs several at once, a sound signal and a light signal and a ground mark and a bright panel, each covering a gap the others leave, so that whichever sense a searcher brings to bear picks something up. By the end you will be able to explain when and why a party signals for help and why it usually stays put, set out the principles of a signal that reads as human, give the international distress conventions in sound and light, lay out the ground-to-air visual code and the body signals to an aircraft, mark and work a safe place for a helicopter, use mirror, fire, smoke, and improvised markers to attract both air and ground searchers, and say how the maritime International Code of Signals fits alongside.

Key Terms

Distress signal: any agreed signal that calls for urgent help, given in regular sixes or threes so that it reads as a deliberate human call and not as chance.
Ground-to-air visual code: the agreed international set of large symbols, laid on the ground in panels, branches, or trampled lines, that passes a short fixed message to an aircraft overhead.
Body signals: signals made to an aircraft with the arms and body, used to answer a circling aircraft or to ask it to land.
Heliograph (signal mirror): a mirror or bright surface used to flash sunlight at a searcher, visible at great distance.
Contrast: the difference between a signal and its background that lets the signal be seen; a signal that blends in is no signal at all.
Helicopter landing site (HLS): a clear, marked, prepared area chosen so that a helicopter can approach and land or winch safely.
Downwash: the violent column of air thrown down and out by a helicopter's rotor, strong enough to hurl loose kit and blind those nearby with grit or snow.
Staying put: the decision of a lost or stranded party to remain in one findable place rather than move, so that searchers can close on a known point.
International Code of Signals (ICS): the international maritime code of flags, lights, and sound by which ships and shore stations pass set messages, including distress, by single letters and short groups.

When and why to signal, and the decision to stay put

A party signals when it needs help it cannot provide itself and cannot reach by other means: when it is lost and cannot recover its position, stranded by ground, weather, or injury, or holding a casualty whose needs exceed what the party can give. The signal is a sound decision made early rather than late, while there is still light, energy, and material to make it with. A party that waits until it is exhausted and the light is gone has thrown away the means of being found. Signal early, signal in daylight if you can, and keep something in reserve for the dark.

The first and hardest decision is usually whether to move or to stay put, and the rule here leans firmly toward staying, tying back to the lost-procedure of Lesson 01: a soldier unsure of their position should stop, think, and not compound the error by wandering. A party that stays gives searchers a fixed point to close on, can build and tend a proper signal, conserves its strength, and keeps a casualty still and sheltered. A party that wanders is a moving target that may walk out of the search area, leave its casualty behind or carry them into worse ground, and spread its sign thin. Search teams plan around a last known point and a likely area; a party that holds still lets that plan work, while one on the move can undo a whole day's search by drifting across the boundary into ground already cleared.

With a casualty the case for staying is near absolute: you do not drag an injured person across country to be found when you can make yourself found where you are. Move only when staying is clearly more dangerous than going, when the position is exposed to rising water, rockfall, avalanche, or a failing shelter. Then move deliberately, by map and compass, to the nearest safer place that is still findable, leaving clear sign of your direction behind you so that a search reaching the old position can follow on. The choice is between making yourself found and making yourself lost again; in almost every case, stay and signal.

The principles of a good signal

A signal works only if a searcher, on the ground or in the air, notices it and reads it as a human call for help. Four principles make that happen, and a soldier should judge every signal against them.

Contrast. The signal must stand out from its background. Dark against snow, light against dark ground, a hard straight edge against the broken lines of nature, a moving flash against a still landscape. A panel the colour of the hillside, or a fire whose grey smoke matches a grey sky, is invisible. Choose colour and material for the greatest difference from the surroundings, and reassess as light and weather change, because a signal that contrasts at noon may vanish at dusk.
Regularity and artificiality. Nature is irregular; human signals are not. Straight lines, right angles, exact repetition, and even spacing all read as deliberate. Six even whistle blasts, three fires in a tidy line, a clean angular letter laid on the grass: each says plainly that a person made it. This is why the distress conventions repeat in regular threes and sixes, and why a single long shout is far weaker than a steady, counted rhythm.
Siting to be seen. A signal hidden in a gully or under a canopy helps no one. Place it where it can be seen from a distance and, for air signals, from directly above: on open, high, or exposed ground, clear of overhanging trees. Think about the lines a searcher is likely to fly or walk, and put the signal across them. A second signal on a different aspect of the ground doubles the chance of being seen by a search coming from an unexpected direction.
Size and movement. Bigger is better, and moving beats still. From the air a small mark vanishes; ground-to-air symbols are made large, the limbs of each letter several metres long and broad enough to read, because an aircraft passes quickly and high. A flash, a waved panel, or a column of smoke draws the eye where a static mark would be missed. Make every signal as large as the party can manage, and add movement wherever you can.

Hold these four in mind and you can improvise a signal from anything and still get it right, because the principles, not the particular kit, are what make a signal work.

The international distress conventions

There is an agreed international way to call distress with sound or light, and every soldier should know it cold. The distress signal is six blasts on a whistle, or six flashes of a torch, given steadily across one minute; then a pause of one minute; then the six are repeated, and so on for as long as the party can keep it up. The standard reply, by which a searcher signals that the call is heard and help is coming, is three blasts or flashes in a minute, a minute's pause, and again.

INTERNATIONAL DISTRESS (sound or light)

   CALL    :  6 blasts / flashes in one minute,  then PAUSE one minute,  repeat
   REPLY   :  3 blasts / flashes in one minute,  then PAUSE one minute,  repeat

   Keep the rhythm.  Keep the count.  Keep going.
   A searcher may catch only one repetition in many before fixing you.

The deeper point is the pattern, not the exact count. Any signal given in regular sixes or threes, by whistle, torch, horn, shout, banging metal, or waved light, reads as distress to anyone trained, precisely because nature does not repeat in tidy bursts. Three of anything, evenly spaced, is the universal shorthand for "I need help": three fires, three blasts, three flashes, three marks on the ground. The pause matters as much as the blasts. It lets a distant searcher confirm a rhythm, take a bearing on the sound or light, call for quiet to listen again, and shout or flash a reply into the gap. A continuous, panicked din gives them nothing to lock onto and exhausts the signaller in minutes.

A soldier with nothing but a whistle and a torch carries a recognised distress signal in their pocket. The whistle is the better daytime tool: it carries through wind and rain and over ground where a voice is lost within a hundred metres, costs almost no effort, and never tires the way a shout does. The torch is the night tool, carrying through darkness when nothing else will, and its flashes can be counted at a great distance. Neither costs battery to speak of nor any skill but discipline: keep the rhythm, keep the count, keep going. Set one soldier to the task and rotate the duty so the signal never lapses, because the one repetition a searcher happens to catch may be the hundredth you have sent.

Ground-to-air signalling: the visual code

When an aircraft may pass overhead, a party can pass it a short fixed message with the standard ground-to-air visual code: large symbols laid on open ground in any material that contrasts, panels or clothing or a sheet, branches, stones, banked earth, fabric, or lines trampled into long grass or stamped into snow. The symbols are made big, with bold straight limbs several metres long and a stroke wide enough to read from height, sited in the open where an aircraft will see them from directly above, and made to contrast hard with the ground beneath. The code is deliberately small so that survivors with no manual to hand can remember it. These are the symbols that matter:

GROUND-TO-AIR VISUAL CODE  (lay LARGE and in CONTRAST)

   V    Require assistance
   X    Require medical assistance  (serious casualty)
   N    No   (negative)
   Y    Yes  (affirmative)
   |    Proceeding in this direction      ( draw the line / arrow the way you have gone )
   ->   Proceeding in this direction      ( arrow head shows the route taken )

   ( a survivor may also see, in the fuller code: )
   F    Require food and water
   I    Require medicine / serious injury
   ||   Require map and compass
   LL   All is well   (no help needed)
   K    Indicate direction to proceed     ( aircraft answers a lost party )
   JL   Aircraft seen / understood        ( acknowledgement laid by survivors )

Learn the first five cold, because they cover almost every situation a small party meets. V is the plain general call: require assistance, send help. X changes the rescue, telling the aircraft there is a serious casualty and medical aid is needed, which means a different team, different kit, and often a winch rather than a landing. Y and N are the answering pair: they let a circling aircraft put a yes-or-no question, by its movement or by radio relay, and get a clear answer laid on the ground. The direction sign, a bold line or an arrow, tells searchers which way a party has moved if it has been forced to leave the spot, so that a search reaching the last known point is sent on the right line rather than left to guess. Those five, laid large and in contrast, are the working kit; the rest of the code is useful to recognise but secondary.

A few rules make the symbols work. Lay them where an aircraft will pass and look down, on the most open ground you have. Make them at least several metres to each limb, far larger than feels necessary, because height shrinks everything. Build the stroke from a continuous, dense line, not a scatter of objects, so it reads as a solid mark. Keep the shapes square and angular, because nature has no straight edges and the eye picks them out at once. Anchor light material against the wind so a panel letter is not rearranged into nonsense or blown away. And if you must choose, lay one symbol perfectly rather than three badly: a single clean X that an aircrew can read beats a sprawl of half-formed letters they cannot.

Body signals to an aircraft

Where a party has no material to lay symbols, or an aircraft is already circling and a faster answer is needed, it can answer with body signals, made by standing in the open and using the arms and body clearly and slowly so they read from the air. Stand where the aircrew can see you against a clean background, face the aircraft, and make each movement large, deliberate, and held; a quick, casual wave can be mistaken for a friendly greeting rather than a call for help.

BODY SIGNALS TO AN AIRCRAFT  (stand in the open, face the aircraft, hold each signal)

   Both arms raised straight up in a "Y"      YES  /  PICK US UP  /  land or recover us
   One arm raised, the other low (an "N")      NO   /  do not land here
   Arms held straight out to the sides         we have a radio / all is well
   Both arms waved across the body, low        do NOT land  /  keep clear
   Lying flat on the ground, arms out          we need urgent medical help

The signal a soldier needs first is the affirmative: both arms raised straight above the head in a "Y", which says yes, we need you, land or recover us. It is unmistakable, it reads from a long way off, and it mirrors the Y of the ground code so the two reinforce each other. To wave an aircraft off, where a landing is dangerous or unwanted, both arms are swept low across the body, the clear "keep clear" that the eye reads as a refusal rather than a welcome. Be deliberate throughout: hold the signal until you are sure it has been seen, repeat it on each pass, and never let a half-hearted gesture leave the aircrew guessing whether you are in trouble or merely saying hello.

Marking and working a helicopter landing site

If a helicopter is to land or winch, the party can help by preparing and marking a site, but the governing rule is safety: a helicopter is dangerous to be near, and the aircrew are in charge. Never approach an aircraft unless the crew signal you forward; never approach from behind, where the tail rotor turns unseen and the pilot cannot watch you; and always move in clear view of the pilot, in the front arc, low and slow. A landing site has a name and a drill, and a soldier should be able to set one up and behave correctly on it.

HELICOPTER LANDING SITE  (HLS):  prepare, mark, behave

   THE SITE     flat, firm, open ground;  clear approach;  NO wires / trees / poles / slopes
                far larger than the aircraft;  no loose dust, snow, or debris if avoidable
   THE WIND     show it:  stand upwind, back to the wind, arms out toward the landing area
                ( the pilot lands INTO wind;  smoke, a streamer, or grass also shows it )
   LOOSE KIT    weight, stow, or hold EVERYTHING;  downwash will throw a sheet into the rotor
   PEOPLE       keep everyone back and low at the edge;  shield eyes from grit and snow
   APPROACH     wait for the crew's signal;  go from the FRONT, in the pilot's view, never the tail

To prepare a site, choose and clear a reasonably flat, firm, open area, far larger than the aircraft, with a clear approach and exit and no wires, trees, poles, or slopes on the line in. Wires are the great killer: they are nearly invisible from the air, so a site under or near power or telephone lines is no site at all. Signal the wind direction so the pilot can land into wind: stand at the upwind edge with your back to the wind and arms held out toward the landing area, so the aircrew read the wind from your body, or use the column of a smoke fire, a light streamer, or tossed grass to show it. Above all, secure every loose item, because the downwash of a helicopter, the column of air it drives down and out, will hurl a loose sheet, pack, map, or garment up into the rotor or against the airframe with force enough to bring the aircraft down; anything not laid out as a fixed marker is weighted, stowed, or firmly held. Keep the rest of the party back and low at the edge of the site, faces turned from the storm of grit and snow the downwash raises, and a casualty shielded. Then wait. Do not move toward the aircraft, do not throw anything, do not run, until a crew member clearly signals you forward, and then go only from the front, in the pilot's view, bent low, never toward the tail. The drill for working with aircraft is taught and practised in person, on a real site with real aircraft, because the danger is immediate and the margin small.

Mirror, fire, smoke, and improvised markers

Beyond sound and the ground code, a party has several powerful ways to draw a distant eye, and the longest-reaching in daylight is the signal mirror or heliograph. A mirror, a polished tin lid, a glassy phone screen, the bright underside of a foil blanket, any of these can catch the sun and throw a flash visible for many miles, far beyond the reach of a shout, a panel, or even smoke. To aim it, hold the mirror just below the eye and extend the other hand at arm's length toward the target with the fingers spread; bring the bright spot of reflected sunlight onto your outstretched fingers, then move the mirror a hair so the flash slides off your fingertips and onto the aircraft or searcher beyond, and rock it gently to make the flash blink. When no aircraft is yet in sight, sweep the flash slowly along the horizon and across any high ground, because the flash may be seen long before you can see who is watching. The mirror needs sun and a little practice, done in person; aimed well, it is the single most effective daytime signal a soldier can carry.

Fire and smoke are the classic distress signal, and the recognised form is three fires or three columns of smoke, set in a line or a triangle and spaced well apart so they read as deliberate human work rather than one chance blaze. Fire serves by night, its light carrying far in the dark and visible from the air long after sound has failed. Smoke serves by day, and the colour is chosen for contrast against the background: dark smoke, made by throwing rubber, oil, or oily rags onto a hot fire, stands out against snow, pale rock, and a light sky; light or white smoke, made by piling green leaves, grass, moss, or damp material onto strong flames, stands out against dark ground, forest, and shadow. Keep the makings ready beside a small fire or hot embers so a full column can be raised the moment an aircraft is heard, since a quick dense column shows both your position and, by its drift, the wind to the aircrew. Fire in the field demands care, especially in dry country and near a casualty or fuel; in cold and snow the same fire that signals also keeps the party alive, and the building and tending of it is covered in full in the Cold-Weather Operations and Survival course.

SMOKE FOR CONTRAST

   Background is LIGHT (snow, pale rock, bright sky)  ->  make DARK smoke
                                                           ( rubber, oil, oily rags )
   Background is DARK (forest, dark rock, shadow)      ->  make LIGHT / white smoke
                                                           ( green leaves, grass, damp moss )

   THREE fires or columns  =  recognised distress.  Space them; keep makings ready.

Improvised panels and markers make use of whatever a party carries. A brightly coloured bivouac sheet, a survival blanket with its bright or reflective side turned up, spare clothing, a foil liner, or a poncho pegged out in the open all make a contrasting panel that an aircraft or a far searcher can catch, and they can be arranged into the letters of the ground code as easily as laid flat. Anchor them hard against the wind, turn the side that contrasts most toward the sky, and lay them large and flat in the open where they will be seen from above. A bright panel weighted at the corners, a mirror kept to hand for the sun, a torch kept for the dark, and the makings of a smoke fire ready to light make a complete signalling set built from ordinary kit, and a soldier who carries and keeps it ready is rarely without a way to be seen.

Attracting ground searchers

Not all help comes from the air; much of the RKA's search work is done on foot by parties moving across the ground, and a lost soldier helps by being noticeable to them too. Sound carries to a near searcher when sight does not: the whistle in regular sixes, a shout, or metal banged in rhythm will reach a search line working through woodland, scrub, or mist that cannot yet see you, and a search will often halt and call for silence to listen, so the disciplined, repeated rhythm with its pauses is exactly what lets them take a bearing on you. Light does the same after dark: a torch flashed in sixes, a chemical light, or a small fire or torch left burning at a fixed point draws a night search to a known spot, and a steady light is often easier to find than a moving one.

If the party has had to move, it marks its route and leaves sign so searchers reaching the last known point can follow the trail: an arrow of stones or branches at a junction, scuffed or trampled ground, a marker tied to a fence or a branch at eye height, a note left weighted under a stone giving the time, the party's state, and its intended direction. The principles are those for air signals: make your sign contrast, make it regular and clearly human, place it where a searcher will actually pass, and make it as plain as you can. A party that stays put, keeps a steady sound and light signal going, lays the ground code or a bright panel for the air, and has left clear sign behind any move it was forced to make has done everything in its power to be found, from whichever direction help comes.

The maritime equivalent: the International Code of Signals

Everything so far is land signalling, for the hills, the forest, and the open country where the RKA does most of its search work. The sea and the coast have their own complete system, the International Code of Signals (ICS), and a soldier should know it exists and where it is taught, because a search may run down to a shoreline, a flooded valley, or open water where the maritime conventions take over.

The ICS is an agreed international code by which ships and shore stations pass set messages using flags, flashing light, sound, or radio, so vessels of any nation understand one another without a shared language. Its heart is a set of single-letter signals, each a complete urgent message on its own, hoisted as a flag or sent by light or sound. A handful matter for distress and rescue: O ("Oscar") means man overboard; V ("Victor") means I require assistance; W ("Whiskey") means I require medical assistance; and the two-flag group NC is the recognised signal of distress. The same code carries the visual conventions a coastal searcher must read, including the agreed answers given between a person in distress on shore and a rescue craft offshore. The ICS is the maritime sibling of the land signals in this lesson, the same small, fixed, internationally understood set turned to the water. It is taught in full in the Signals and Field Communication course, alongside the radio voice procedure that is always the first resort; treat this paragraph as a signpost to it, not a substitute.

In Practice: A Stranded Party on the Ridge

A four-soldier party working a search on a high open ridge loses a member to a bad ankle on broken ground as cloud closes in and the radio, screened by the mass of the ridge, will not raise base. The section commander makes the decision Lesson 01 trained into them: they do not press on or try to carry the casualty down through cloud, but stay put on a broad open shoulder and set about being found. The casualty is sheltered from the wind, kept still, and kept warm, the first aid drills of the Combat First Aid course applied while the others build the signals.

One soldier is given the whistle and a single task: sound the distress call, six blasts across a minute, a minute's silence, six again, and keep it going whatever else happens, with a mate ready to take the duty when the first tires. A second tramples a large X into the snow on the open shoulder, several metres to each limb, the stamped lines dark against the white, telling any aircraft there is a serious casualty and medical aid is needed. Beside it they peg a bright survival blanket flat, reflective side up, anchored at the corners against the wind, and they lay the makings of a smoke fire ready to raise the instant an engine is heard. A torch goes into a pocket for the dark, and the signal mirror is kept to hand against any break in the cloud that brings the sun.

When at last a search helicopter beats up the valley below the cloud base, the work pays off. The soldier on the fire lights it and feeds it oily rags for a dark column that shows both the party's position and, by its drift, the wind. Every soldier secures every loose item against the coming downwash, the casualty is shielded, and two of them stand clear on firm open ground, facing the aircraft, both arms raised in a steady "Y": pick us up. They hold it through each pass, do not move toward the aircraft, and wait until a crew member clearly signals them forward, then go in low from the front, in the pilot's view, never near the tail. The party that stayed, signalled in human threes and sixes, marked itself for the air, showed the wind, and obeyed the aircrew is lifted off whole. A party that had wandered into the cloud, dragging its casualty, might still be looking for a way down.

Check Your Understanding

When should a party decide to signal for help rather than press on, and why does this lesson, like Lesson 01, lean so firmly toward staying put? Why is the case for staying put near absolute when there is a casualty, and what are the few conditions under which a party should move anyway?
State the international distress signal and its reply in both sound and light, and explain why the pause matters as much as the blasts and why any signal repeated in regular sixes or threes reads as distress. Which of the whistle and the torch is the better daytime tool, which the better tool by night, and why?
Give the meanings of the ground-to-air symbols V, X, N, Y, and the direction sign, and the body signal for "pick us up". When working a helicopter landing site, why must all loose kit be secured, why must wires be avoided above all, and why must a party never approach the aircraft until signalled and never from the tail?

Reflection (write a short paragraph): This lesson teaches the skill of being found, and most of an RKA soldier's career will be spent on the other side of it, searching for those who need finding. Knowing how the lost should make themselves seen, the contrast, the regular human pattern, the staying put, the running of several signals at once, sharpens how you will search for them. Think of a real search the RKA might mount, in the hills, in flooded country, or down to a coastline, and describe how understanding both sides, the lost party's signals and the searcher's eye, would make you better at the humanitarian work the Army exists to do. What does it say about the seriousness with which to take the practical instruction that follows, where these signals are made real and certified in person?

Summary

A party signals when it is lost, stranded, or burdened with a casualty and cannot reach help otherwise, signalling early while light and energy remain; it usually stays put to be findable rather than wanders, especially with a casualty, in keeping with the lost-procedure of Lesson 01, and moves only when staying is plainly more dangerous, leaving clear sign of its direction. A radio is the first resort where it works; these signals are for when it does not.
A good signal obeys four principles: it contrasts with its background, is regular and clearly artificial so it reads as human, is sited to be seen from a distance and from directly above, and is as large and as moving as can be managed; the surest approach runs several signals at once.
The international distress signal is six whistle blasts or torch flashes in a minute, then a minute's pause, repeated; the reply is three; the pause lets a searcher take a bearing and answer, and any signal in regular sixes or threes reads as distress, so a whistle (by day) and a torch (by night) give a recognised call in wind and darkness.
The ground-to-air visual code passes a fixed message with large contrasting symbols: V require assistance, X require medical assistance, N no, Y yes, and a line or arrow for direction of travel; for body signals, both arms raised in a "Y" mean pick us up and both swept low mean keep clear. A helicopter site (HLS) is cleared flat and free of wires, the wind shown, all loose kit secured against the downwash, and the aircraft never approached until the crew signal you forward, then only from the front and never the tail.
A signal mirror flashes sun for miles and is the best daytime signal; three fires or smoke columns are a recognised distress sign, dark smoke against snow and light smoke against dark ground; improvised panels and clear ground sign (sound, light, marked route) draw both air and ground searchers. The maritime equivalent is the International Code of Signals (single-letter signals such as V "require assistance", W "require medical assistance", O "man overboard", and the NC distress group), taught in full in the Signals and Field Communication course. Every one of these skills is taught and certified in person.

Attracting Help: Emergency and Ground-to-Air Signals