April 5, 2024: The American Zumwalt-class DDG-1000 destroyers have turned into a very expensive experiment into how not to build a new class of warships. Because of the high cost, which was eventually about $8 billion per ship, only three were ordered. Note that a Virginia class SSN (attack submarines) costs about $4 billion each.

Construction of the Zumwalts began in 2011. Only one of the three is in service, and limited service at that. The second ship is in the water but still having weapons and equipment installed. The third ship is also in the water but not completed and is undergoing sea trials to make sure it can operate at sea. All three Zumwalts won’t be in service until 2025. Their problems are many, but the key ones are an overly ambitious design and a willingness to keep spending more money to make it work. The previous Burke-class destroyers worked and cost $2 billion each.

The U.S. Navy encountered seemingly endless problems and delays in getting the first of three new DDG-1000 class stealth destroyers into service. The original date for being fully operational was 2021 but that soon slipped to 2025 or later. The delays stem from continued efforts to deal with a list of 320 serious deficiencies compiled after the first Zumwalt completed sea trials in early 2016. All this increases costs and those have risen annually since construction began. Those unanticipated, but not unexpected, increased costs are the reason the ships cost more than three times what the earlier Burkes did. So far Zumwalt is not as effective as the latest Burkes.

At this point the total cost for the DDG-1000 program will be over $23 billion, meaning each of the three DDG-1000s to enter service will probably cost about $8 billion. This includes $10 billion in research and development, which was to be spread over 32 DDG-1000s. Even so, that would have been $312 million per ship. Among its many failures, the most notable one was the inability to get its two 155mm guns operational. The DDG-1000 was designed mainly to provide gunfire support for marines but comparable new and better technology, like the HIMARS vehicles that carry six guided missiles each. The marines found that HIMARS vehicles carried in amphibious support ships, could be brought to the helicopter flight deck, and fired at targets on land or even other ships. Amphibious support ships carry a battalion of marines along with a lot of support equipment. These ships have helicopters for transporting the marines ashore plus some landing craft for moving combat and support vehicles as well as supplies to shore. Among the vehicles was one or more HIMARS, which is seen as a flexible artillery weapon.

The navy abandoned the custom gun system for Zumwalt and is replacing those two guns with four 2.2 meter missile tubes designed to house C-HGB, or Common Hypersonic Glide Bodies missiles. The C-HGB is a collaborative development between the Army and Navy to develop a missile that can hit any target in the world using a non-nuclear warhead.

This significant shift in the mission profile of the Zumwalt destroyers underscores a broader strategic shift within the U.S. Navy. Originally designed for more traditional armaments, the Zumwalt and its sister ships will now be at the forefront of deploying non-nuclear hypersonic missiles.

The modifications on the first Zumwalt Began in 2023. The conversion cost $155 million and is to be completed by late 2025. A second of the three Zumwalts will undergo a similar modification.

Replacing the 155mm guns was not the only modification to Zumwalts. In 2017 the air defense systems were upgraded. This involved a $100 million upgrade of the fire control systems to handle the new RIM-175 SM-6 anti-aircraft missiles. The Zumwalts were designed as multi-purpose vessels able to carry out anti-air, anti-submarine, anti-ship, and land attack missions. Land attack was to be carried out by two 155mm guns firing GPS guided shells. These shells could accurately hit targets over a hundred kilometers inland. The navy auditors found that the 155mm shells would be too expensive if only three Zumwalts could be built. The two 155mm guns are being replaced with hypersonic missiles that can hit ships or land targets. The new SM-6 antiaircraft missiles are effective against other ships as well as aircraft.

The SM-6 is an upgrade of the older SM-2 in that it can now do everything better, especially the way it handles surface targets. This capability was developed in 2017. A test was conducted using a retired U.S. frigate as a target. One SM-6 missile sank the ship. This was made possible because of modifications to the SM-6 guidance system. SM-6 entered service in 2011 and anti-ship capability was added later. The initial order for SM-6 was for 1,200 missiles. These are replacing all the older SM-2s, which entered service in 1979 and SM-3s, an advanced version of SM-2 that shoots down ballistic missiles. The SM-2 ER, which entered service in 1980, was also capable of being used against ships. SM-6 has a longer range and more effective guidance and resistance to countermeasures like jamming than the SM-2 and is meant to deal with aircraft, cruise missile and ballistic missiles more effectively as well. Max range of the SM-6 was initially 240 kilometers but quickly increased to about 340. The longer range and higher speed of the SM-6 make it particularly effective against other ships. The SM-6 is basically the existing SM-2 anti-aircraft missile with the more capable guidance system of the AMRAAM air-to-air missile, as well as general improvements in the electronics and other components.

The upgrade also enabled Zumwalts to use the Maritime Strike variant of the Tomahawk cruise missile. This version received a new guidance system that enables the cruise missile to hit moving ships at sea. This version can also hit land targets as well and has a range of 1,700 kilometers. The anti-ship version needs some other ship, aircraft, or satellite to determine the general area where the target is. Zumwalts have 80 VLS (Vertical Launch Tubes) containing either anti-ship, cruise, or anti-aircraft missiles. Now the mix of missiles will be SM-6, SM-3 (the anti-missile version) or Tomahawk. The new VLS cells are larger so they can handle the new hypersonic missile.

The Zumwalt class was designed with stealthy superstructure that deceives enemy radars to believe they have spotted a much smaller ship. In reality Zumwalt’s are huge, at 14,000 tons. This means a destroyer that is 194 meters long, and 25.5 meters wide. The crew of 150 sailors operates a variety of weapons, including the 155mm guns being replaced with large hypersonic missiles, 80 VLS cells, two 30mm automatic cannons for close-in defense, six torpedo tubes, a helicopter, and three helicopter UAVs. Zumwalt has sonar, Aegis radar, electronic warfare equipment, and the ability to shoot down ballistic missiles.

Zumwalts proved too expensive to build in the quantities desired. Many other nations do not have the procurement problems the U.S. Navy is suffering from. Attempts to fix the U.S. Navy procurement mess constantly run into political opposition and that is another matter altogether. In 2009 the navy decided to build only three of the Zumwalts instead of 32. To cope with the loss of new destroyers the navy resumed building older DDG-51 Arleigh Burke class destroyers. It was a matter of cost. The new Zumwalt destroyers and slightly larger versions designated as cruisers would cost more than $4 billion each if built in large quantities. The Burkes cost $1.9 billion each. The last of 62 original Burkes was ordered in 2002 and the last of those entered service in 2011. But by 2019 the new Burkes were entering production. Currently there are 71 with plans for 19 more if the navy can get the money. The DDG-51 is less than half the cost of the Zumwalts, but some navy officials believe that, in the long run, the larger and more expensive Zumwalts would be a better investment. The key problem here is the inability of the Navy to control costs, and cost estimates, and the inability of the DDG-51s to provide space for new technologies.

Cutting the Zumwalt order to three ships meant the GPS guided shell for the 155mm guns was too expensive at about a million dollars a shell. The first Zumwalt was supposed to enter service in 2016 and the initial sea trials were promising. But the problem began to appear in the many new systems and technologies in the Zumwalt. At this point all three are not expected to be in service until the late 2020s. Experience with the Zumwalts, the Seawolf SSN, Ford class carriers and smaller LCS or littoral combat ships indicated that the navy has not yet fixed its fundamental inability to design and build new ships. The navy plays down how serious this problem is, but the seriousness of the problem is only made worse by the Chinese success at building new ship classes much more quickly and on budget. The U.S. Navy used to be able to do this and the loss of that capability continues to be the most serious threat the navy faces and the one too few navy leaders are willing to take on, partly because much of the problem is Congressional interference prompted by defense contractors. Congress uses its power over flag rank promotions to have its way here.