Place it just before the airstrike footage begins, after Enemy Spotted sets up the threat and before Bomb Has Been Planted raises the stakes for the final push, so the sequence builds from warning to support to explosion.
このサウンドについて
This is a short, clipped military radio announcement saying friendly AC-130 support is overhead, delivered in a calm, authoritative male voice over about two seconds. It feels reassuring and tense at once, like backup has just arrived when a fight is turning. The line comes from Call of Duty, where it announces the AC-130 gunship killstreak.