Zumwalt-class destroyer

The Zumwalt-class destroyer (DDG-1000) is a future class of United States Navy destroyer, designed as a multi-mission ship with a focus on land attack. The lead ship is named the Zumwalt for Admiral Elmo Zumwalt. Following Navy tradition, this will be called the Zumwalt-class. The prior program name was DD(X), a scaled back progeny of the larger tonnage vessel planned in the DD-21 program initated when the DD-21 program had large funding cuts.

Proposal

Originally the Navy had hoped to build 32 of these destroyers; that number was later reduced to 24, then to 7. The reason for this reduction is the high cost of several new and experimental technologies that are set to be incorporated in the destroyer. The US House of Representatives remains skeptical of the DDG-1000 destroyer program for financial reasons and has therefore allotted the Navy only enough money to begin construction on one DDG-1000 destroyer as a "technology demonstrator." The funding allocation for the DDG-1000 destroyer was included in the National Defense Authorization Act of 2007, but they can purchase more if it works.

However, the 2007 appropriations bill passed on September 26, 2006, by the House and later by the Senate allotted 2.6 billion USD for the funding and building of two Zumwalt-class destroyers. Under this current plan, Bath Iron Works in Maine and Northrop Grumman's Ingalls Shipbuilding in Mississippi will build one ship each.

Among U.S. warships in development, the DDG-1000 is to be preceded by the Littoral Combat Ship and followed possibly by the CG(X) cruiser, concurrent with the CVN-21 aircraft carrier. The DDG-1000 program resulted from a large re-organization of the DD21 program when Congress cut its budget by over half (Part of the SC21 program of the 1990s).

The Zumwalt-class destroyer is multi-role and designed for sea warfare, anti-aircraft, and naval fire support. They take the place of the battleships in filling the former congressional mandate for naval fire support, though the requirement was reduced to allow them to fill this role. The most numerous Navy main sea warfare ships are, and will remain for the foreseeable future, the Arleigh Burke class destroyers and Ticonderoga class cruisers. All are part of the Aegis system.

Design and development

The DDG-1000 will feature the following: a low radar profile; an integrated power system, which can send electricity to the electric drive motors or weapons, which may someday include railguns; a total ship computing environment infrastructure (TSCE-I), serving as the ship's primary LAN and as the hardware-independent platform for all of the ship's software ensembles; automated fire-fighting systems and automated piping rupture isolation. It is being designed to require a smaller crew and be less expensive to operate than comparable warships. It will have a wave-piercing "tumblehome" hull form whose sides slope inward above the waterline. This will reduce the radar cross-section, returning much less energy than a more hard-angled hull form.

In late 2005, the program entered the detail design and integration phase, in which Raytheon is the Mission Systems Integrator. Both Northrop Grumman Ship Systems and General Dynamics Bath Iron Works share dual-lead for the hull, mechanical, and electrical detail design. BAE has the advanced gun system and the MK57 VLS. Almost every major defense contractor (including Lockheed Martin, Northrop Grumman Sperry Marine, L-3 Communications) and sub-contractors from nearly every state in the US are involved to some extent in this project, which is the largest single line item in the Navy's budget. During the previous contract, development and testing of 11 Engineering Development Models (EDMs) took place:

The DDG-1000 with planned features.

• Advanced Gun System
• Autonomic Fire Suppression System
• Dual Band Radar [X-band and L-band]
• Infrared
• Integrated Deckhouse & Apertures
• Integrated Power System
• Integrated Undersea Warfare
• Peripheral Vertical Launch System
• Total Ship Computing Environment
• Tumblehome Hull Form

Many of the ship's features were originally developed under the DD-21 program ("21st Century Destroyer"). In 2001, Congress cut the DD-21 program by half; to save it, the acquisition program was renamed and heavily reworked. According to a Government Accountability Office report, milestones include:

• Formal program launch, April 2002
• Preliminary design review, March 2004
• Lead ship authorized, March 2005
• Critical design review, August 2005
• Start fabrication, June 2007
• First ship launched, June 2012

USS Hayler (DD-997) (1982) was the last Spruance-class destroyer, and DDG-112 (2010) is to be the last Arleigh Burke-class destroyer. The Zumwalt's hull number will be DDG-1000.

History and development

The House of Representatives is against the DDG-1000 and has cut some funding, preferring to build another Arleigh Burke class destroyer and the new littoral combat ships. The Senate supports the DDG-1000 and continues to approve more funding.

It was reported on October 17, 2005, that an October 5 Pentagon report recommended "canceling the DD(X) destroyer being developed by Northrop Grumman Corp." [2]

On November 23, 2005, the Defense Acquisition Board approved a plan for simultaneous construction of the first two DDG-1000 ships at Northrop’s Ingalls yard in Pascagoula, MS and General Dynamics’ Bath Iron Works in Bath, ME. However, as of that date, funding had yet to be authorized by Congress.

In late December 2005, the House and Senate agreed to continue funding the DDG-1000 program; however, only seven of these ships will be built under the 2005 authorization instead of the originally planned 23 to 30.

In April 2006, the first of the class was announced and will be named the Zumwalt and carry the designator DDG-1000. The ship will be named to honor the former Chief of Naval Operations Admiral Elmo R. “Bud” Zumwalt Jr. So doing, the Navy will eschew the guided missile destroyer sequence begun with DDG-1 Gyatt and continue in the previous "gun destroyer" sequence left off with DD-997 Hayler. The second ship of the Zumwalt destroyer class will be named in honor of Jeremy Boorda, a popular past CNO, the only one to have risen from the enlisted ranks.

DD(X)/DDG-1000 initiated debates and controversy

General controversy: cost and technology

There was much controversy over the development of the Zumwalt class destroyer with regards to its funding and its role. Questions have been raised in the Congress over the cost of the destroyer program with support for the ships dwindling in light of the mounting cost of the planned new technologies in the vessels. To counter the high cost of this class, the Navy has drastically reduced the number of Zumwalt destroyers it plans to build and has implemented an incremental funding method to help pay for them, but doubts in Congress remain over the ship's ability to meet the demands and roles the U.S. Navy has for them. As a consequence of this perception, Congress has thus far allotted only enough funding for two Zumwalt-class destroyers; these destroyers will serve as "technology demonstrators." Congress has also stated that it has mixed feelings over the use of incremental funding for ship classes, a decision which may affect funding for the class in the future.

The Zumwalt class appears to be multiple times the cost of a Arleigh Burke class ship with the first DDG-1000 to cost over 3 Billion USD due to various reasons. One is the amortized R&D costs over a decade of development, a common thread in post-Cold War weapon systems (for example, the "300 million dollar" F-22 Raptor fighter jet actually has a flyaway cost of less than half that, due to the amortized R&D cost which is absorbed in the price of the initial order of 180 jets purchased by the Air Force).

Artist's impression of the Advanced Gun System aboard a DD(X) Destroyer

Naval fire support role and the DD(X)

A controversial point of the DD(X) destroyer(s) is their planned naval surface fire support role. The original DD21 and the Arsenal Ship had more serious NFS capabilities, which would meet a Congress-mandated requirement related to the Iowa-class battleships. The requirement was eventually relaxed, the battleships stricken from the registry, and the Navy left with small tonnage ships for NFS.

The official position of the US Marine Corps and the US Navy is that the DD(X) destroyer(s) will be adequate as naval surface gunfire support ships, although there are dissenters. In March 2006, the Iowa and Wisconsin were struck from the NVR. However, Congress remains "deeply concerned" over the loss of naval surface gunfire support they could provide and noted that "navy efforts to improve upon, much less replace, this capability have been highly problematic." The US House of Representatives asked that the battleships be kept in a state of readiness should they ever be needed again and directed the Navy to increase the number of Arleigh Burke-class destroyers that are currently being modernized. The modernization includes extending the range of the 5 inch guns on the Flight 1 ships with extended range guided munitions (ERGMs) that would enable the ships to fire projectiles about 40 nautical miles inland.

The DD21 was to be have been designed around an advanced "vertical gun" system, which would only have been compatible with guided projectiles, though the project ran into serious technology/cost programs and was radically scaled back to a more conventional 6.1 inch Advanced Gun System (AGS). This fires a variety of both guided and unguided shells and offers significantly more flexibility than the "VGAS" (Vertical Gun for Advanced Ships) concept.

It was slated for a hull of around 14,000 tons displacement, but the DDG-1000 is of smaller displacement and firepower characteristics compared to the original DD21 design (roughly 16,000 tons). This would have allowed 117-128 VLS rather than 80 VLS as on the DDG-1000.

The DDG-1000 has 50% more displacement than the Arleigh Burke class, and both by terms of displacement and firepower is more in line with light cruisers. The Arleigh Burke class, currently still in production with a projected total of 62 ships, is anticipated to be the Navy's main air defense ship for the next 4 decades.

Up to 2006, the remaining Iowa-class battleships were kept on the Naval registry, in part to fill a naval fire support role. The Navy had never had any intention of recommissioning either battleship; their high manpower and fuel requirements were far in excess of the Navy's projected allotment of either for the fire support role. Their 16" (406 mm) guns are capable of firing 2,700 lb projectiles approximately 24 nautical miles inland, but very large crews are required for them; whereas the current 5" weapon can be operated by a single loader and the 6.1" weapon requires no crew members. Experimental sabot shells for the 405 mm with multiple times this range were proposed, but none ever reached prototype stage. Since the 1992 decommissioning of USS Wisconsin and USS Missouri, all naval gunfire support has been through missiles or through 5"-armed cruisers and destroyers and 3"-armed frigates. DDG-1000 is noted to be able to fire a specially designed "guided" artillery shell some 63 nautical miles inland. However, this shell has a reduced warhead size and uses new technology, so most of the shells carried on the DDG would have vastly shorter range.

The same shells placed in a sabot 406 mm round would achieve the same effect with much farther range but considerably reduced accuracy due to the lower inherent accuracy of the 16" weapon and a much lower rate of fire (2 rounds per minute per tube versus 8-10) due to the slower manual reloading of the 16" weapon, versus fully automatic loading of the 6.1" weapon. With only a few hundred shells at its disposal, the DDG-1000 could fire at a cyclic rate for less than an hour before needing resupply (in practice, the DDG-1000 would only seldom be firing at a cyclic rate). In fact, with planned number of long-range shells, the DDX could only fire a fraction of that time at the longest range.

6.1 inch (155 mm) against 16 inch (406 mm) guns

While smaller calibre guns (and missiles) have been used for centuries in naval fire support, very large guns have special capabilities beyond that of mid-range calibres. US battleships were re-activated three times after WWII specifically for NFS, and their 16 inch gunfire was used in every major engagement of the U.S. from WWII to the Gulf War.

It is claimed by the proponents of the new design that the 6 inch guns, unlike the much larger 16 inch, have a smaller "danger space" and are easier to use as a close-support weapon for friendly troops, who are less likely to be wounded or killed by friendly fire as they advance. In either event, the primary weapon of close support is aircraft (especially the A-10 Warthog, which has excellent rough-field handling characteristics and very long on-station loiter time) and is likely to remain aircraft for the foreseeable future, with ships filling an allegedly necessary secondary role of heavy bombardment.

While the 16 inch guns can fire larger shells when needed, the 6.1 inch guns cannot. However, the 16 inch weapon is not sufficiently accurate for a close-support weapon. The battleships can also use their 5"/38, which supposedly can actually carry a similar weight bursting charge, even though the 6.1 inch/62 gun fires a projectile approximately four times heavier and much longer-ranged than the 5 inch projectile used by Iowas 5"/38 Mk. 12. The 6.1 inch gun fires a 200 pound unguided bombardment projectile at a range (elevation unknown but presumably 45 degrees) of 24 km, comparable to the 16"/50 at an elevation of 20 degrees (the 16"/50 has a range of 38 km at 45 degree elevation) and much longer than the 5"/38's range of only 16 km (at 45 degrees). The modern 5"/54 weapon has a range at 45 degree elevation of 21 km and the 5"/62 of 23 km. The two share a common projectile which is 25% heavier than the 55 pound surface bombardment high-explosive projectile fired by the 5"/38, and the 62-calibre weapon is compatible with a newly-developed 127 mm extended-range guided munition which shares many design features with the 155 mm LRLAP. The 14 calibre-long ERGM is incompatible with the smaller 38 calibre weapon because there is insufficient barrel length to develop high muzzle velocity with the larger and heavier munition.

155 mm gunnery is a well-used calibre in American military strategy on land-based systems. The Advanced Gun System, which uses 155 mm ammunition (though not the same ammunition as the Army's 155 mm gun artillery systems) is a versatile artillery piece for both land and sea combat in many applications.

While it is always possible to put a smaller bursting charge in a shell, the 16" weapon's bursting charge is only 48 pounds of a 2,000 pound projectile, and most of the danger to unarmoured or lightly-armoured objects (people and vehicles) is shrapnel thrown out from the point of impact, up to 300 meters (330 yards) away in the case of the heavy 1,900 or 2,700 pound projectiles. The analog computers used in the Iowa-class fire control system have a circular error probable of over 100 meters, more than double the CEP of the FCS developed for the AGS. A 100 meter CEP is acceptable when fighting guns against a 200 meter long enemy warship but wholly unacceptable when firing into a battlefield situation where friendly soldiers are operating within 50 or fewer meters of the enemy (the effective range of modern personal weapons is generally less than 50 meters without mechanical compensation for the motion of the human body). A subcalibre sabot round had already been partially developed for a battleship gun; 11 inch subcalibre saboted long-range round for the 16"/50 Mark 7 and was tested in the 1960s. Another, even longer range one was proposed in the late 1980s and was evaluated. The studies for this formed the basis for the original (not current) long range AGS gun in the DD21 (but not DDG-1000).

Proponents of the 16 inch weapon claim frequently that only battleship-calibre exceeds merely adequate fire support (often going further than that, deriding lesser weapons as "popguns"). Smaller calibres have good track records in most applications.

In the Pacific theatre of World War II, while battleships armed with 12 inch, 14 inch, and 16 inch weapons gave good fire support, so too did cruisers armed with 6 inch (152 mm) and 8 inch (203 mm) guns, with a lower throw weight than the modern 6.1 inch (155 mm) Advanced Gun System weapon. Since the 1992 final decommissioning of the battleships, 5" (127 mm) and 3" (76 mm) calibres have been the primary tools of naval gunfire support, with aircraft and missiles providing heavy firepower in all applications where heavy firepower is called for. The GBU-39 Small Diameter Bomb has roughly the same explosive charge as a 1900 lb. 16" high explosive shell, while its overall weight is only 250 lbs. The heaviest aircraft-dropped bombs are over 2,000 pounds, heavier than a battleship's shore-bombardment shells. The 2,700 pound "superheavy" shells developed for World War II were solely intended for sea combat against other battleships, as their fragmentation and explosive characteristics were considerably inferior to the 1900 pound HE shell.

Cruiser-calibre weapons have been occasionally tested since the retirement of the last Baltimore and Cleveland-class cruisers, with the 8" Major Calibre Lightweight Gun tested in the 1970s (and nearly accepted for the Ticonderoga-class cruisers) and the 6.1" AGS in the present. Battleship-calibre weapons were periodically reactivated via the re-activation of existing battleships. There have been some experimentation with 16" guns, such as the EX-148 round. No new battleship-calibre weapons have been created or tested, however, since the beginning of World War II.

The question of 6.1" versus 16" weapons, however, sidesteps the question of whether tube-based artillery firepower remains actually necessary. In order to employ guns with any degree of accuracy, ships must operate in "brown water," close to shore and with minimal maneuverability to evade harm in the case of attack. Modern gun artillery systems are minimally used due to vulnerability against counterfire; tanks use direct-fire 100 to 120 mm cannon for attack and .50 calibre machine guns for defense. Artillery brigades generally use rocket systems (such as MLRS) rather than guns; rockets are more difficult to ballistically track because they are engine-propelled for part of their flight. In realistic terms, naval guns in modern warfare are used primarily against naval targets, missiles against land targets, and aircraft against both land and sea targets. 6+ inch (cruiser calibre) weapons are, however, demonstrably more useful against ship targets than 5" and that will be their probable primary employment. During Operation Iraqi Freedom, the Marines effectively left their artillery "at home," preferring air power and missiles to either land- or sea-based artillery.

Resistance to underwater attack

Due to their immense size and armour battleships are more resistant to mines and torpedoes than smaller modern ships. These are a particular hazard when operating slowly and close in to shore. However, because of their great size, powerful magnetic and acoustic signatures and lack of space available to mount effective torpedo countermeasures, they are considerably more vulnerable to torpedo and mine assault than more modern ships. That is to say, while they may be able to absorb more hits, they will be successfully attacked more frequently because they are more attractive targets and have fewer active defenses. The Iowa class ships, during their 1980s deployments, were almost wholly dependent upon escort for torpedo and mine defense, their onboard defenses were limited to two AN/SLQ-25 Nixie towed torpedo decoys.

Modernization vs all-new

While a proposal claiming that it would cost $450-550 million (1991 dollars) to modernize the battleships suggests favorable conditions over the cost of purchasing a new Arleigh Burke class guided missile destroyer ($1.2 billion (2006 dollars)), the study never covered modernizing the ships to a fully new configuration and left out several critical system modernizations, such as altering the ships for compatibility with modern missile systems. While the first two Zumwalt class ships cost several times the cost of the Arleigh Burke, that cost includes amortized research and development costs that would not be included in the price of subsequent hulls.

Modernizing ships like the USS Iowa and USS Wisconsin is one option. Both are now over 60 years old, yet have had numerous refits. Indeed, there are ships older than their last re-fit still serving. Modernization would be needed but would save the cost of building a new hull, engines, and propeller among other items. Their hulls, however, were built with a 30-year active lifespan in mind and have been used for 20, albeit intermittently. To get more than another 10 years of operational life out of the ships would require an extensive overhaul comparable to an aircraft carrier SLEP or RCOH, a very expensive prospect (the RCOH program is a 2 billion dollar "top to bottom" refit, as well as a complete re-engining and replacement of their steam turbines). While they received many updates during the 1980s refit, the equipment they received in the 1980s was not state of the art even then, and the data links used to synchronize the modern battle force of the US Navy were not even invented yet. While a proposal claiming that it would cost $450-550 million (1991 dollars) to modernize the battleships (compared to the cost of $1.2 billion (2006 dollars) for a brand new Arleigh Burke class guided missile destroyer), this proposal was made in the 1990s and proposed reactivating the ships in a 1996 configuration, without VLS for modern missiles, simply as gunships. The high fuel consumption and manning requirements of the ships also argues against their retention, since other than their big guns, they add no capability to the fleet that is not already duplicated by active ships.

Missiles

The Harpoon Anti-Ship Missiles are used on both the DDG-1000 and 1980s refitted Iowa-class. The 1980 Refit battleships carried 16 RGM-84 Harpoon Anti-Ship Missiles and 32 BGM-109 Tomahawk Cruise Missile.[3] The DDG-1000 is planned to have 80 PVLS tubes. [4] An Arleigh Burke-class ship has 90 (Flight I/II) or 96 (Flight IIA) VLS cells or 122 for a Ticonderoga class ship. Both Burke and Tico class ships also carry 16 Harpoon missiles. Flight IIA Burkes have provisions for Harpoons but do not normally carry them to reduce topweight. The Zumwalt will carry in standard operation many more Tomahawks than either Tico or Burke class ships because of the primary tasking of the other vessels as anti-aircraft ships.

One point of contention is that it did not include vertical launch systems for missiles-for firing Tomahawk missiles, as now Tomahawks have been converted to a VLS design and the VLS Tomahawk is incompatible with the old ABL launcher; all old ABL Tomahawks have been either converted to VLS weapons and subsequently expended in the years since the retirement of the last ABL ships, or scrapped. Expert analysis would be needed to determine the impact of this, with the impact ranging from simply not using them or converting to VLS.

In defense against missiles, the Iowa class ships are very vulnerable to missile attack, much more so than a more modern vessel. Because of their design and the requirements of the 16" guns, they cannot mount directors for surface to air missiles, and their missile defenses are limited to SRBOC chaff launchers and Phalanx CIWS, both of which are severely inadequate to deal with modern missile threats, unlike the Zumwalt class, which will mount the Evolved Sea Sparrow Missile as its primary antimissile defense.

Training

The specializations required to operate the Iowa class ships continue to exist in the US Navy, which is a moot point when all new ships require new training. During the 1980s reactivation of the Iowas, training was further aided by senior manpower from specially reactivated sailors who had sailed aboard them during previous service periods (World War II, Korea, and Vietnam), who the helped train their younger counterparts on equipment. This created a new generation of people trained on the equipment, so that while people who served on them in Korean War are now in their 70s, much of the latest battleship sailors are not even 40 years old yet.

DD(X) does not meet NFS requirements proponents

There is a camp that allege that the US still has a use for its battleships and want Iowa and Wisconsin reactivated or, at the very least, maintained with the United States Navy reserve fleets (or less formally, the "mothball fleet").

Members of this camp allege that the US Navy has a "battleship bias" and that the DD(X) destroyer’s guns are not as superior as the 16 in guns on the battleships. Some members of this camp even go so far as to claim that the companies overseeing production of the DD(X) destroyer(s) are only in it for the money they will receive as part of the so-called military-industrial complex. They also point out that the first DD(X) destroyer is not slated to enter service until 2013 at the earliest, leaving a multi-year gap without any direct replacement for this loss of long-range seaborne artillery. This "gap," however, has existed since 1992 and is largely filled at present by air power.

External links

• navytimes.com: DD(X) gets go-ahead
• General DD(X) Destroyer page
• globalsecurity.org report on the DD(X) Destroyer program
• Overview of the DD(X) Destroyer program and its capabilities
• USS Zumwalt.com - www.usszumwalt.com
• DDG1000 DDG1001 DDG1K.com Website devoted to the Zumwalt-Class Destroyer
• Concept of employment for naval surface fire support (near term capability)
• Information on the Advanced Gun System set to be installed on the DD(X) destroyers

Websites run by companies involved in the DD(X) Destroyer program

• DD(X) Destroyer page maintained by the companies involved in its construction
• Raytheon webpage for DDG 1000 Program

Government reports regarding the DD(X) Destroyer program

• DoD press release: Navy Designates Next-Generation Zumwalt Destroyer
• House letter recommending against a "winner take all" construction strategy for the DD(X) destroyer program
• 1995 US General Accounting Office report on the US Navy’s Naval Surface Fire Support program
• 2004 US Government Accountability Office Report: Challenges Facing the DD(X) Destroyer Program
• 2005 US Government Accountability Office Report: Issues Related to Navy Battleships
• 2005 CRS Report for Congress: Navy DD(X) and CG(X) Programs: Background and Issues for Congress