A U.S. Navy Phalanx Gun Targeted a Civilian 737 This Week

In a video that went viral yesterday, you can see a Mk 15 Phalanx Close-In Weapon System (CIWS) begin to target what appears to be a civilian 737.

In an example of our collective dark sense of humor in the military, you can hear a sailor scolding the automated Phalanx as if it were a naughty toddler about to touch a hot stove.

It’s worth noting that this probably happens all the time. Ever flown into Reagan Washington National Airport (DCA)? Your plane was likely lit up like a Christmas tree.

The CIWS (often spoken as “sea-wiz”) in the video appears to be mounted on a U.S. Whidbey Island-class amphibious dock landing ship, although it could also be a Harpers Ferry-class.

According to the U.S. Navy, the CIWS is a fast-reaction, detect-through-engage, radar-guided, 20-millimeter gun weapon system. It’s used primarily as an inner layer of protection against anti-ship missiles (ASM), aircraft, and small boats that have penetrated other fleet defenses.

The weapon system has various modes, from fully manual, to semi-automated (where it needs approval to fire), to fully automated mode. In fully automated, the CIWS can engage targets as it sees fit, under certain conditions.

Over the years, the CIWS has undergone a number of upgrades to both its gun and its radar. Since 2015, the Navy has upgraded all Phalanx systems to the Block 1B variant.

Block 1B incorporates an automatic acquisition video tracker, optimized gun barrels (OGB), and Enhanced Lethality Cartridges (ELC) for additional capabilities against asymmetric threats such as small maneuvering surface craft, slow-flying planes and helicopters, and drones.

The CIWS has downed friendly aircraft before: In 1996, the Phalanx onboard the Asagiri-class Japanese destroyer JDS Yūgiri accidentally shot down a U.S. A-6 Intruder from the aircraft carrier…