How do I call an airdrop with the signal flare gun?

The signal flare gun calls an airdrop to wherever you fire it. It can't be crafted — you'll only find one in loot.

How to use it. Fire the flare upwards. It has to go up steeply — aim at least 45 degrees above the horizon — and it has to reach open sky: a flare that hits a roof, a bridge or a rock face doesn't count. The flare burns for about eight seconds.

If the shot was good, a plane is called to the spot under the flare. It takes a minute or two to arrive.

Expect company. The drop lands where you fired, and you won't be the only one who noticed. Call it somewhere you can hold, not in the open, and be there when it lands.