The U.S. Navy is working with NATO allies and other countries to develop a next-generation ship-based Sea Sparrow missile engineered with an improved, high-tech guidance system, service and industry officials explained.
The Evolved Sea Sparrow Missile Block 2, or ESSM, is a new version of an existing Sea Sparrow currently protecting aircraft carriers, destroyers, cruisers, and other vessels against anti-ship missiles and other short-range threats to ships, Navy officials said.
Navy officials have upgraded the missile to counter threats expected in the 2020s, said Lt. Kurt Larson, a Navy spokesman. These threats include short to medium range missiles, small fast-boat attack, enemy unmanned aerial vehicles as well as air-launched munitions.
The ESSM Block 2 will be designed to be compatible with existing systems and replace the baseline ESSM weapon on many platforms, Larson added.
The Block 2 is engineered with what’s called a semi-active, active guidance system, meaning the missile itself can achieve improved flight or guidance to its target by both receiving and actively sending electromagnetic signals, said Daniel M. Lambert, an official with Raytheon missile systems.
The ESSM baseline missile uses radar technology to locate and then intercept a fast-approaching target while in flight using what’s called a “shipboard illuminator,” Lambert explained.
“The illuminator is an RF signal that bounces off the target. The antenna in the nose in the guidance section [of the missile] sees the reflected energy and then corrects to intercept that reflective energy,” said Lambert.
The current ESSM missiles use what’s called a semi-active guidance system, meaning the missile itself can receive electromagnetic signals bounced off the target by the shipboard illuminator. The ESSM Block 2’s active, semi-active guidance includes illuminator technology built onto the round itself such that it can both receive and send important electromagnetic signals, Lambert explained.
ESSM Block 2 can use shipboard illumination or its own active seeker, he added.
The missile will be designed to intercept threats fired in bad weather as well as what’s called the “high-diver” threat from an enemy aircraft and “sea-skimmer” threat wherein an incoming projectile flies close to the water, said Lambert.
“Proven dual mode guidance technology leveraged from existing family of missiles will provide an upgraded capability that will be required to deliver the necessary ship defense capability to pace the threat, counter future advanced Anti-Ship Cruise Missile threats and surface threats,” Larson said.
The ESSM Block 2 program is a NATO cooperative development effort for which the U.S. share is 40% of the total development cost, Larson explained.
The most recent ESSM Block 2 development contract was issued by the Navy to Raytheon Missile Systems on Dec. 27, 2012.
“The contract has a period of performance from the award date through the Milestone B decision leading to Engineering and Manufacturing Development,” Larson added.
Australia, Canada, Denmark, The Netherlands, Norway, Turkey and the United States are all currently reviewing an ESSM Block 2 Memorandum of Understanding, or MOU, designed to solidify the developmental path for the missile system through it next phase, Larson said.
“ESSM Block 2 Development MOU completed formal negotiations on June 21, 2013. The latest version of the [Engineering and Manufacturing Development] MOU is currently in staffing with the final version planned to be sent to the participating nations for staffing and signature no later than Oct. 11 2013. The objective is to have a fully executed MOU by June 30, 2014,” said Larson.
Also, the ESSM Block 2 will go through a Systems Functional Review in October 2013 and Wind Tunnel testing in December 2013, he added. The program Preliminary Design Review is currently scheduled for late FY14.
One analyst said the ESSM Block 2 could enable certain ships with longer range missiles to effectively allocate which missiles to use in particular circumstances.
“When you have a ship that has less expensive shorter range systems, you are able to pick and choose what missiles you are going to use for the threats. You can husband your resources so that long range missiles can go after more aggressive, longer-range threats,” said Bryan McGrath, a retired Navy officer who is now managing director at FerryBridge LLC, a defense consulting firm based in Easton, Md.