Guide · Signalling

Ground signals for aircraft

From the air, a person on the ground is tiny and easy to miss. Large shapes and symbols that contrast with the ground can be spotted from far away and tell rescuers what you need.

Make it big and bold

• Make each symbol at least 3 metres long, and bigger if you can — 10 metres is better.
• Lines should be as wide as you can manage, ideally a metre or more.
• Choose open ground: a clearing, a beach, a hilltop or a snowfield. Avoid places hidden by trees.
• Use contrast. Dark rocks or branches on snow or sand. Light-coloured material, stripped bark or bright clothing on grass or earth.
• Straight lines and sharp angles stand out because they rarely occur in nature.

International ground-to-air symbols

These simple shapes are widely recognised by rescue aircraft:

• V — we need help
• X — we need medical help
• Arrow — we have gone this way
• N — no
• Y — yes

If you can only make one, make a large X or a V, or write SOS.

Materials you can use

• Rocks, logs and branches
• Bright clothing, tarps, survival blankets or sleeping mats
• Trenches dug or trampled into snow, sand or long grass — the shadows make them visible
• Turf turned over to show darker earth underneath

Weigh light materials down so wind doesn't move them.

Three of anything

Three of anything in a line or triangle is a common distress signal: three fires, three piles of rocks, three bright objects. Space them evenly, about 30 metres apart if you have room.

Shadows and sun

In low morning or evening sun, raised symbols cast long shadows that make them easier to see. Building up the edges of a symbol, or digging a shallow trench, adds shadow.

Moving on

If you leave a spot, make a large arrow pointing the way you've gone. Leave a note somewhere obvious and sheltered, with the time, your direction and how many of you there are.

Answering a pilot

If an aircraft has seen you, it may rock its wings from side to side or flash its lights. Stay where you are and keep signalling until help arrives.

When you are safe

Break up or remove your signals once you've been rescued, so they don't trigger another search later.

This article is in the Grid Survivor app, searchable with no signal. Get the app · £4.99