By Mass Communication Specialist 3rd Class Daniel Schumacher

BREMERTON, Wash. – Sailors aboard the Nimitz-class aircraft carrier USS John C. Stennis (CVN 74), shipyard workers from Puget Sound Naval Shipyard and Intermediate Maintenance Facility, and technicians from Naval Sea Systems Command (NAVSEA) are upgrading Stennis’ Phalanx Close-in Weapons Systems (CIWS) to a new model that will significantly improve the ship’s ability to defend against close-range threats.

The CIWS is an autonomous fast-reaction, radar-guided, 20 millimeter machine gun weapon system that automatically detects, evaluates, tracks, and engages high speed, close-range air targets, discharging as many as 4,500 rounds per minute. The new CIWS model, Block 1B baseline 2, adds the ability to counter surface threats and slower air targets such as helicopters, and unmanned aerial systems through the addition of an integrated infrared camera system.

“Although the outside [of the CIWS block 1B baseline 2] looks nearly identical [to the older CIWS], just about everything on the inside has been significantly upgraded and improved,” said Field Service Technician Tom Fox, the NAVSEA onsite installation coordinator, from
Shepherdsville, Ky. “The old mounts are archaic in comparison to this new model.”

The Alteration Installation Team from Puget Sound Naval Shipyard (Shop 41) first met with Stennis’ Combat Systems Department Jan. 14 for an initial plan-of-actions briefing about how the two will be working together throughout the CIWS upgrade process.

Shop 41 is responsible for most of the overhaul process to include removing most of Stennis’ existing CIWS equipment, systems, and platforms and then installing the new CIWS Block 1B models in its place while Combat Systems Department assists with other procedures, such as equipment tag-outs, that would delay the install process if done improperly.

“Combat Systems’ assistance has been greatly appreciated by our team,” said Fox. “Installing these mounts on a ship as large as Stennis would have been a nightmare without their help.”

According to Fox, both the port and starboard sides of Stennis will each have one platform with an upgraded CIWS, while the third mount will be completely removed from the ship.

“Stennis still has full coverage with two CIWSs and actually an increased defensive capability with the new CIWS [Block 1B baseline 2] model,” said Chief Fire Controlman Matthew Moulton, Combat Systems 7th Division Leading Chief Petty Officer, from Cleveland.

One of the added features of the Block 1B baseline 2 is the ability for CIWS technicians to manually operate the system using a hand control unit and a monitor that displays a live video feed from the infrared camera system.

“We’ll have better defensive capability and improved detection capability,” said Ensign Michael Schmart, from Kissimmee, Fla., Combat Systems 7th Division Officer. “We’ll be able to engage both air and surface threats, making the CIWS an even greater value to the ship’s self-defense systems.”

Once the CIWS upgrade is complete, Stennis will conduct several performance tests, including live-fire exercises, in order to certify the system as mission ready.

Stennis is currently undergoing a Docking Planned Incremental Availability (DPIA) maintenance period at Puget Sound Naval Shipyard and Intermediate Maintenance Facility.

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