The
Arleigh Burke-class guided missile destroyer was the first of a new generation of warships. Although designed and designated as destroyers, the size and capability of these ships meant that they ended up effectively filling the role previously occupied by the missile cruisers. As the years have passed, the modular nature of their combat systems has allowed them to easily accommodate new weapons and missions, until today they stand alone as the most capable multi-mission surface combatants afloat.
Arleigh Burke Flight I
Arleigh Burke (DDG-51) commissioned in 1991 with just three missiles: SM-2MR, the conventional
land attack Tomahawk, and Harpoon. Although it is almost certain that she was she was designed for the nuclear and antiship versions of Tomahawk, those were withdrawn from service with the end of the Cold War and were likely never carried by any ship of the class. Further, delays with the Vertically Launched ASROC (VLA) program meant that weapon was also was not available when
Arleigh Burke joined the fleet. While VLA was declared operational shortly after the second member of the
Arleigh Burke-class commissioned, procurement ended early and it was never carried in large numbers.
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| Arleigh Burke in 1993: 50x SM-2MR, 32x TLAM, 8x VLA, 8x Harpoon |
Arleigh Burke Flight II
In 1998, the first Flight II ship,
Mahan (DDG-72), commissioned. In addition to various small improvements, Flight II marked the introduction of Aegis Baseline 5 and the extended range SM-2 Block IV. However, delays with that missile meant that it did not become operational until 1999, and procurement was
cut short at just 100 missiles, making them a rather rare commodity. So far, I have been unable to determine if SM-2ER was ever backfit to the Flight I Baseline 4 destroyers in anything other than a BMD role.
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| Mahan in 1999: 8x SM-2ER, 42x SM-2MR, 32x TLAM, 8x VLA, 8x Harpoon |
Arleigh Burke Flight IIA
In 2000,
Oscar Austin (DDG-79) joined the fleet as the first Flight IIA destroyer. Unlike the earlier ships, the Flight IIA gained an additional six VLS cells by omitting the integral loading cranes. More importantly, these ships were outfitted with Aegis Baseline 6, which includes support for the Evolved Sea Sparrow Missile. Quad-packed four to a VLS cell, ESSM increased magazine depth and provided another layer of air defense. However, shrinking design margins and the virtual disappearance of a hostile surface force meant that the Mk 141 canisters for Harpoon were eliminated.
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| Oscar Austin in 2001: 8x SM-2ER, 46x SM-2MR, 8x ESSM, 32x TLAM, 8x VLA |
Ballistic Missile Defense Upgrades
Beginning with
Decatur (DDG-73), the Flight I ships began being fitted with Aegis BMD. This consisted of two weapons: SM-2 Block IVA for terminal defense and SM-3 Block IA for exo-atmospheric midcourse intercepts. These were first tested at sea in 2006 and 2007, respectively. However, this upgrade was not fully integrated with the Aegis combat system and left the ships unable to simultaneously perform BMD and AAW.
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| Decatur in 2007: 8x SM-3, 8x SM-2ER, 34x SM-2MR, 32x TLAM, 8x VLA, 8x Harpoon |
In 2016, to rectify this deficiency, the four destroyers forward deployed to Spain to conduct missile defense patrols
were equipped with SeaRAM launchers in place of their aft Phalanx mounts. Because SeaRAM is fully autonomous, this provided a basic self-defenses capability while in BMD mode. However, by this point the VLA inventory had fallen well below 400 weapons, reducing the number carried by each ship.
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| Porter in 2016: 8x SM-3, 8x SM-2ER, 36x SM-2MR, 11x RAM, 32x TLAM, 6x VLA, 8x Harpoon |
In 2017, the first Baseline 9 ship,
John Finn (DDG-113), joined the fleet, introducing integrated air and missile defense as well as SM-6. Effectively an improved version of SM-2ER, SM-6 incorporates active radar homing and is capable of engaging air and surface targets from over the horizon. With over five hundred SM-6 procured to date, it is available in much larger numbers than SM-2ER ever was. Further, production of the ESSM Aegis variant resumed in 2014 after a five year pause, allowing for more to be carried by each ship. Today, Baseline 9 is also being added to Flight I destroyers as part of the ongoing modernization program that is making the oldest ships in the fleet among the most capable.
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| John Finn in 2018: 8x SM-3, 16x SM-6, 30x SM-2MR, 16x ESSM, 32x TLAM, 6x VLA |
Given that SM-2 has not been procured for years and the Cold War stocks are reaching the end of their lives, we can expect that a mix of SM-6 and ESSM will eventually replace SM-2 entirely on the Baseline 9 ships. This should be helped by the pending introduction of ESSM Block II, which adds an active radar seeker and makes the weapon combat system agnostic (meaning there will no longer be separate variants for Aegis and Mk 29). 2018 should also see the introduction of the far more powerful 21” diameter SM-3 Block II. Looking further into the future, it is likely that either LRASM or NSM to be added and a VLA replacement will also be required.
