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EX-171 ERGM Extended-Range Guided Munition

A key element of U.S. Naval forces' power projection capability, the 5-inch, rocket-assisted Extended Range Guided Munition (ERGM) , will provide surface combatants the ability to support forces ashore with responsive, sustained, and accurate firepower. ERGM's increased range and precision guidance provide a revolutionary capability in support of the U.S. Marines and other ground forces ashore. ERGM uses a high energy propelling charge and rocket motor to achieve maximum projectile range and will be fired by the new 5-inch, 62-Caliber Mod 4 gun now being installed on Arleigh Burke (DDG-51)-class destroyers beginning with USS Winston Churchill (DDG-81).

The Extended-Range Guided Munition is a 12-caliber rocket-assisted projectile capable of carrying a 4-caliber submunition. Unitary warhead constructs are also under consideration. The 110-pound aerodynamic projectile is five inches in diameter and 61 inches in length, and uses a coupled Global Positioning System/Inertial Navigation System (GPS/INS) guidance system. The GPS guidance is tightly coupled to an inertial guidance system that is resistant to jamming, which will enable the ERGM round to attack targets in a heavy electronic countermeasures environment.

The submunition warhead configuration for ERGM will consist of 72 EX-1 submunitions per round. The EX-1 is a variant of the U.S. Army-developed M80 Dual-Purpose Improved Conventional Munition (DPICM), which incorporates a shaped charge and an enhanced fragmentation case for use against material and personnel targets. The ERGM's submunitions will be uniformly dispensed within a pre-determined area that depends upon the specific target to be attacked and the altitude at which the submunitions are released. ERGM's range and precise GPS targeting capability will improve Naval Surface Fire Support (NSFS) and provide near-term gunfire support for expeditionary operations, suppression and destruction of hostile anti-shipping weapons and air defense systems, and naval fires support to the Joint land battle.

The MK45 Mod 4 incorporates improvements to the Fleet's current operational MK45 Mod 2 5-inch gun mount that enable the enhanced gun to provide long range fires. These improvements include structural enhancements for handling the higher firing energy (18 MJ required by the EX-171 extended range guided munition (ERGM) versus 10 MJ needed for conventional 5-inch ammunition), a new 62 caliber barrel, and an ammunition recognition system. The MK45 Mod 4 will still be able to fire all conventional 5-inch ammunition in the inventory. With ERGM rounds the MK45 Mod 4 will reach ranges in excess of 60 NM to support Marines and soldiers on the battlefield with precision fires.

When full rate production commences in FY07, a competitive procurement would be awarded under a fixed price contract. The gun was being developed under a sole source arrangement with United Defense, the sole source manufacturer of the 5"/54 MK 45 MOD 2. The Fire Control (MK 160) is being developed by the Naval Surface Warfare Center, Dahlgren and the propelling charge is being developed by the Naval Surface Warfare Center, Indian Head since these system changes are modifications to current government owned/supplied equipment.

ERGM Program Chronology

ERGM is being developed utilizing Integrated Product/Process Teams with Raytheon Missile Systems as the prime contractor and the Naval Surface Warfare Center as the Technical Design Agent. The ERGM development contract was awarded to Texas Instruments (now Raytheon Missile Systems) as a result of a competitive acquisition process. TI provided a corporate investment of $55M that was applied to development. The extended ERGM Team includes Alliant TechSystems (rocket motor); General Dynamics (control actuation system); L3-IEC (GPS); American Nucleonics (anti-jam circuitry); BAE Systems (inertial measurement unit); Enser (flight battery) and Primex (payload).

Milestone I/II was reached in July 1996, allowing the ERGM to enter EMD. Developmental work continues as the program overcomes technical challenges. Work also continues on increasing lethality, designing the highly accurate guidance system that can withstand the harsh environment encountered during a gun firing, and other areas (including a cargo variant) to provide cost-effective, accurate and lethal munitions that meet NSFS requirements.

In working to realize a round with a range capable of supporting units ashore, the ERGM program confronted a series of tough technical challenges. Testing results, however, have provided promising mitigation approaches to each of the identified technical risks. For example, a tail fin, redesigned to reduce drag, demonstrated in the April 1999 wind tunnel tests a predicted range increase of about 10%. This increase will yield a maximum range for ERGM in excess of the objective of 63 NM.

When the technical challenges became apparent and well defined, the Program Office initiated an independent assessment of the ERGM development program. The assessment, conducted by the Massachusetts Institute of Technology's Lincoln Laboratories, in Boston, concluded, "ERGM development is blazing a new technology trail and problems of the type being encountered (and solved) are to be expected. The Navy should stay the course. ERGM will serve the Navy, the Marine Corps, the Army, and the Nation very well in the future."

The Naval Surface Fire Support Program Office (PMS529) announced the ERGM development team successfully conducted an all-up round guided flight of an Extended Range Guided Munition (ERGM) on 10 December 2001 at White Sands Missile Range, White Sands, NM. The test, designated Control Test Vehicle-2 (CTV-2), again demonstrated the ability of the ERGM round to perform as predicted after being fired from a gun. All CTV-2 test objectives were met including canard deployment, rocket motor operation, telemetry function, and Global Positioning System (GPS) acquisition and track. The significant achievement beyond that of the CTV-1 flight test was the successful operation of the tactical five-card Guidance Electronic Unit (GEU) design.

The Naval Surface Fire Support Program Office at Naval Sea Systems Command and its Extended Range Guided Munition (ERGM) development team conducted successful rocket motor and airframe tests at proof launch pressure (greater than tactical launch pressure). Conducted on May 14, 2002 at Yuma Proving Grounds, in Yuma, Ariz., the tests consisted of seven ERGM test rounds fired at proof pressure. Four of the ERGM rounds contained live rocket motors, while three "slugs" or dummy rounds, with a new tactical tail fin assembly, were fired to evaluate airframe stability. All seven rounds, as indicated by Weibel radar, exhibited stable flight and flew to their expected impact point.

The ERGM program was restructured in FY03 to reflect a requirements change to a unitary warhead. This also led to schedule adjustments supporting an FY06 IOC. A major contract modification was also signed supporting the program revision. In late 2002 the contractor completed its third flight demonstration of ERGM on schedule, which seemed to bode well for meeting the revised contract schedule.

The ERGM program began development with very few of its critical technologies mature, and while progress has been made, program officials did not expect to achieve maturity on all critical technologies until at least February 2004. No production representative engineering drawings were released to manufacturing by the design review; however, by March 2004 over half of these drawings had been released. The program office expected to have a complete and updated drawing package by October 2004. Finally, due to several test failures, the program did not meet a Navy deadline that required successful completion of two land-based flight tests by November 2003. By March 2004 the Navy was conducting an independent assessment of the program's readiness to proceed with further flight-testing. The Navy also issued a solicitation for alternative precision-guided munition concepts that could offer cost savings.

As of late 2004 the expected fielding of the ERGM system for use in upgraded 5-inch guns on current destroyers and cruisers had been delayed from 2001 to possibly as late as 2011. Problems on the ERGM, which has been under development since 1996, led to test failures and delays.

Raytheon Company successfully fired two tactical ERGM (Extended Range Guided Munition) rounds at White Sands Missile Range, N.M., 16 February 2005. Both rounds exited the gun after transferring through a severe gun environment; additionally the tails erected and the rocket motor ignited. Moreover, both rounds achieved stable flight, acquired and tracked GPS satellites, developed in-flight navigational solutions, and guided to the target area more than 40 nautical miles away. The first round flew into the target arena and detonated the warhead.

"Meeting today's objectives with tactically configured rounds validate our technical advancements in the component structure and set the stage for the land based test flight series to begin," says David Martin, Raytheon Projectiles product line vice president. "With the performance we saw today, we've completed the final engineering flight test, gained valuable total system performance data, and demonstrated a revolutionary capability that will fill the gap in naval surface fires as soon as possible with one of the first precision guided munitions to be fired from a gun."

By June 2005 the Project Manager for the Naval Surface Fire Support Program did not have a current and comprehensive Munition test and evaluation master plan or sufficient funding to conduct the developmental, guided flight tests needed to demonstrate whether the Munition will perform reliably. As a result, the Project Manager was executing the Program without adequate developmental test information on the reliability of the Munition while proceeding towards operational testing. In addition, the Project Manager cannot assure the Navy Acquisition Executive that sufficient test data will exist to assess the reliability of the Munition before his decision on whether to commence full-rate production on the Munition. The Navy did not justify the Munition quantity requirements reported in the approved acquisition program baseline agreement and did not have a viable acquisition strategy to immediately procure the Munition. As a result, the Navy had obligated $354 million and planned to obligate an additional $146.1 million in RDT&E funds to continue development of the extended range munitions technology before determining whether it can afford the total cost for procuring and fielding the Munition. Over the program life cycle, the Navy planned to procure an inventory of between 8,500 and 20,780 rounds to equip two full Munition magazines on the destroyers and to replace Munition rounds used for training.

Navy funds in FY2006 provided for the development of two separate 5" guided projectiles; the Extended Range Guided Munition (ERGM) and the Ballistic Trajectory Extended Range Munition (BTERM) as part of the ERM demonstration. ERGM is being executed as a formal ACAT program while ERM is a demonstration project via a Broad Agency Announcement. Both were executed through the end of FY05. In FY06, a full and open competition will be held to select a single 5" guided projectile for System Development and Demonstration leading to an Initial Operational Capability in FY11.

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Page last modified: 07-07-2011 02:50:59 ZULU