The 30mm gun used on the Apache is a single-barrel chain gun, rather than the multibarrel rotary Gatling. But as both are mechanically or power-operated weapons rather than being dependent on the gas generated by their firing, both weapons systems are similar, close cousins if not brothers.
Apache's *chin-mount* underbelly chain gun:
Gatling *mini-gun* in use:
20mm M61 *Vulcan* Gatling-type aircraft gun:
mini-gun mounted as helicopter dsoor gun:
