The Phalanx is an amazingly badass piece of military technology. It’s an automated Gatling gun that fires 20mm rounds at a rate of 4,500 per minute. The Navy primarily uses it to defend ships from incoming missiles.
The Phalanx Close-In Weapons System (CIWS) was developed as the last line of automated weapons defense (terminal defense or point defense) against anti-ship missiles (AShMs or ASMs) and attacking aircraft, including high-g and maneuvering sea-skimmers.
Here’s more video of a live fire test.
Footage shows loading the Phalanx Close In Weapons System (CIWS) “seewiz” and test firing from three different U.S. Navy ships – USS Underwood (FFG-36), USS Nimitz (CVN-68), and USS Antietam (CG-54). The CIWS is a radar guided 20 mm M61 Vulcan Gatling gun autocannon used primarily for defence against anti-ship missiles. It is installed on all U.S. Navy surface combatant ships, and is capable of locking onto incoming missiles and firing 4,500 rounds per minute.