Securing the high seas

Layered defenses protect navies around the world

The guided-missile destroyers USS Kidd, front, and USS Preble steam ahead of the guided-missile cruiser USS Antietam during an exercise on the western Pacific Ocean. (Photo: U.S. Navy)

Layered defense is how we protect U.S. and allied ships and crew members. Think of it in four overlapping layers: long range, medium range, short range and close-in.

There are Raytheon defenses protecting all four layers. For example, the Standard Missile-2 provides long-range defense; Evolved SeaSparrow Missile, medium range; Rolling Airframe Missile, short range; and Phalanx and SeaRAM, both close-in range.

“The offensive posture of a ship is useless without the ability to protect the ship first,” said Gerard Hueber, Raytheon vice president of business development for Strategic and Naval Systems. “When sailors step into harm’s way, their confidence must be in the ship’s layered defense system.”


SM-2 gives navies the firepower to defend against anti-ship missiles and aircraft out to 90 nautical miles. Raytheon is installing active radar target detection into the latest IIIC variant, now in development.

Raytheon restarted the SM-2 missile production line in 2017 to meet demands from international customers.


Navies use the ESSM missile for intermediate-range protection against cruise missiles, helicopters and other ships. It is the foundation of several allied navies' anti-ship, missile defense efforts.

The ESSM Block 2 missile will feature a new guidance system with a dual-mode, active and semi-active radar. This newest variant is on track to enter production and become operational in 2020.

Plans are to produce more than 2,500 missiles, meaning that the Block 2 represents the future of the NATO SeaSparrow program. The ESSM program is a cooperative effort managed by a NATO-led consortium that includes 12 nations: Australia, Belgium, Canada, Denmark, Germany, Greece, The Netherlands, Norway, Portugal, Spain, Turkey and the United States.


The supersonic, quick-reaction RAM missile uses active infrared seekers against weapons or craft that are launched from a short range and travel at high speeds.

The Block 2 variant, the latest evolutionary stage of the RAM missile, features a rocket motor that is larger than the ones on its predecessors, advanced guidance and control and an enhanced radio-frequency receiver that allows it to engage multiple targets simultaneously.

The RAM missile is deployed on more than 165 navy ships in 11 countries, ranging from 500-ton, fast-attack craft to corvettes, the world’s smallest warships. This missile's Block 1A and Block 2 variants may be fired from 11- or 21-round RAM launchers.


The Phalanx weapon system is a rapid-fire, computer-controlled radar and 20 mm gun system that acquires, tracks and destroys close-in threats that have penetrated other ship defenses.

Known as the last line of defense, the electric gun now features a larger magazine for longer engagements.

The Phalanx weapon system is installed on all U.S. Navy surface combatant ship classes and on those of 24 allied nations.


Raytheon’s SeaRAM system is modeled after the Phalanx, replacing the 20 mm Gatlin gun with a launcher that pinpoints its target and fires up to 11 RAM missiles.

“Protecting the mission is paramount and necessary to maintain sea control,” Hueber said.

Published On: 05/17/2019
Last Updated: 05/21/2019