Go Under the Antiaccess Wall
U.S. NAVY (JOHN PARKER)
In “Breaking the Antiaccess Wall” (Proceedings May 2015), Captain Sam Tangredi, U.S. Navy (Retired), correctly emphasizes the Navy requirement to deliver large numbers of cruise missiles to hostile coastal regions to provide continuous, long-range precision fires on enemy communications nodes and critical weapon systems.1 This, he says, would break the antiaccess area-denial (A2/AD) wall. But his call for the renewal of the arsenal ship program of the late 1990s misses the mark. Large cruise-missile-armed surface combatants are not the answer to the Navy’s growing antiaccess and area-denial problem. Instead, the Navy should replace the four Ohio-class conversion guided-missile submarines (SSGNs) with a new class of smaller SSGNs capable of high reaction speeds and armed with a smaller, but still potent, battery of cruise missiles.
An Arsenal Submarine
The need to break through the antiaccess area-denial wall is underscored by A Cooperative Strategy for 21st Century Seapower, which lists A2/AD second among the characteristics of today’s global security environment.2 The U.S. surface fleet faces the very real threat of being pushed away from modern hostile coastlines by numerous, hardened cruise missiles and radar installations, growing subsurface threats, and increasingly sophisticated cyberwarfare capabilities. Since a vulnerable, self-propelled arsenal barge is unlikely to survive the threat, the solution lies in going under the antiaccess bubble. Only the autonomy and stealth of a modern submarine force—well armed with cruise missiles—can counter these risks with impunity.
This growing requirement shortfall for submerged strike capabilities will be exacerbated as the four Ohio SSGNs begin to reach the ends of their service lives. As they decommission, the Block V Virginia-class attack submarines (SSNs) with the Virginia payload module will deploy with additional strike capacity to make up for the capabilities of the SSGNs. The Navy will nevertheless face more than a 50 percent loss in deployable Tomahawks on board its submarines. This is primarily because of the loss of 616 Tomahawk slots from the four Ohio SSGNs out of a force with approximately 1,200 deployable weapons.3 Six new SSGN (X)-class arsenal submarines of the design proposed here could meet this critical shortfall.
A new class of arsenal submarines would need to carry between 80 and 100 Tomahawk missiles. The already existing tubes of the Block V Virginia-class payload module provide an effective method of arming the arsenal submarine. Twelve payload tubes will provide a complement of 84 missiles.4 In addition, it would need a minimum of two torpedo tubes for self-defense and would borrow already designed sonar, periscope, and fire-control systems from the Virginia class to keep down price and development time. The option of refurbishing such equipment from retiring Los Angeles or Ohio-class submarines also exists. The arsenal submarine’s mission is not to be the premier in cutting-edge attack-submarine technology, but rather to center on being affordable and effective in its role as a fast SSGN.
The Price of Victory
The most vital puzzle piece within the maelstrom of Navy ship acquisition complexity is the price tag. Just as the original arsenal ship concept made every effort to increase its attractiveness by decreasing its cost, so should the arsenal submarine. Experts will be quick to point out that any SSGN (X) would far exceed the price of an arsenal ship. Ignoring for a moment the numerous advantages offered by an arsenal submarine over an arsenal ship, attacks on the price of submarine procurement are not supported by the facts. The Seawolf (SSN-21)-class—another once high-speed, high-tech submarine concept that was procured in small numbers (three hulls) two decades ago—was massively over budget and viewed by many in Congress as a procurement disaster.5 The U.S. submarine force has, however, redeemed itself in the last decade with the success of the Virginia-class program which consistently produces submarines under budget.6
Unfortunately, the surface fleet has been less than successful in this regard, producing two extremely expensive surface combatant programs in the forms of the Zumwalt (DDG-1000)-class destroyers and expensive littoral combat ships (LCSs). While the original arsenal ship’s design was to drive toward a single mission concept, the attractiveness of making such a huge, expensive ship into a multi-mission platform might cause procurement cost to spiral upward toward the $13 billion price tag of the three Zumwalt-class destroyers.7 By procuring six arsenal submarines to spread the development cost across more ships, and by limiting the SSGN (X) mission profile—a feat more easily done if a volume constrained hull is laid down—the lead ship of the arsenal submarine would cost an estimated $3.1 billion in 2016 dollars.
But initial procurement is not the only price driver. Manpower expenses significantly contribute to the life cycle cost of any warship.8 The arsenal submarine would reduce manpower costs by relying on a single, attack submarine-sized crew rather than the two larger crews employed on Ohio SSGNs. But removing the blue-and-gold crew system would strain the arsenal submarines’ ability to sustain a forward-deployed posture. Instead, the arsenal submarine should be held in reserve, ready to deploy with extreme speed from a port such as Pearl Harbor to a global hot spot at a moment’s notice. This would enable the SSGN (X) to bring its potent arsenal to bear on targets within days instead of weeks, without the price of a dual crew and without following a traditional deployment cycle. Therefore, the arsenal submarine’s speed is of the essence.
Meet the Need for Speed
To achieve the required speed, the arsenal submarine would sacrifice capabilities in the traditional attack submarine realm and optimize its hull shape for a lower length-to-diameter ratio, which minimizes the frictional resistance to the hull. An SSGN (X) could dedicate a larger amount of the available hull volume and length to the propulsion and reactor spaces to generate more shaft horsepower values than the Seawolf class. By doing this, the SSGN (X) could reasonably achieve a 315-foot length and 42-foot diameter, which would enable it to far outpace Seawolf- and Virginia-class submarines. Such a submarine could make the 5,000-nautical-mile journey from Pearl Harbor to the South China Sea in much less than a week.
By minimizing its cost and maximizing its response speed, the arsenal submarine remains affordable in small numbers to be procured within the next two decades. Production and deployment of the Virginia class would continue to meet the demand for more standard submarine roles such as intelligence, surveillance, and reconnaissance, antisubmarine warfare, and antisurface warfare.
Submarine-based strike missions have become crucial to Navy operations, and this growing need leads to SSNs being pulled away from the roles they were designed to accomplish.9 The submarine strike demand signal will grow even larger as the Ohio SSGNs decommission and Block V Virginia-class SSNs are called to make up for the loss of SSGN-based cruise missiles.
During Operation Odyssey Dawn, for example, the USS Florida (SSGN-782) launched more than 90 Tomahawk land-attack missiles.10 More than three SSNs would be needed to deliver a similar capability and would remove these submarines from other vital missions.
In a full-scale conflict with a first-world nation, every attack submarine available will be needed in antisubmarine and antisurface warfare missions. Meeting strike warfare requirements will be left to vulnerable surface ships unless the Navy fields a new arsenal submarine.
As foreign powers continue to advance their A2/AD strategies and technologies, the requirement for submarine-based strike firepower will grow. By developing a dedicated, high-speed SSGN, the submarine force will be able to continue to meet land attack demands while ensuring that its SSNs can focus on other pressing missions.
1. CAPT Sam J. Tangredi, USN (Ret.), “Breaking the Antiaccess Wall,” U.S. Naval Institute Proceedings, vol. 141, no. 5 (May 2015), 40-45.
2. Ray Mabus, General Joseph Dunford, USMC, Admiral Jonathan Greenert, USN, Admiral Paul Zukunft, USCG, A Cooperative Strategy for 21st Century Seapower, March 2015.
3. Kris Osborn, “Navy Wants 28 More Tomahawks on Virginia-Class Submarines,” 16 March 2015, http://www.dodbuzz.com/2015/03/16/navy-wants-28-more-tomahawks-on-virginia-class-submarines/.
4. CAPT Karl Hasslinger, USN, John Pavlos, “The Virginia Payload Module A Revolutionary Concept for Attack Submarines,” Undersea Warfare, no. 47 (Winter 2012), http://www.public.navy.mil/subfor/underseawarfaremagazine/issues/archives/issue_47/virginia.html.
5. John McCain, “Additional and Minority Views: Additional Views of Mr. McCain,” Senate Report 104-112 – National Defense Authorization Act for Fiscal Year 1996, 1995, http://thomas.loc.gov/cgi-bin/cpquery/? &dbname=cp104&sid=cp104HLTLZ&refer=&r_n=sr112.104&item=&&&sel=TOC_773755&.
6. Dan Ward, “How Budget Pressure Prompted the Success of Virginia-Class Submarine Program,” USNI News, 3 November 2014, https://news.usni.org/2014/11/03/opinion-budget-pressure-prompted-success-virginia-class-submarine-program.
7. Sydney Freedberg, “Cuts to Zumwalt Destroyer Won’t Save Much,” Breaking Defense, 21 September 2015, breakingdefense.com/2015/09/no-cuts-to-zumwalt-destroyer-do-the-math/.
8. LT Johannes Schonberg, USN, “Maximizing Minimum Manning,” U.S. Naval Institute Proceedings, vol. 138, no 1 (January 2012).
9. CDR Mark Gorenflo, USN, CDR Michel Poirier, USN, “The Case for More Submarines,” Undersea Warfare, no. 6, www.public.navy.mil/subfor/underseawarfaremagazine/Issues/Archives/issue_06/more_submarines.html.
10. MCS1 James Kimber, “Florida Returns from Historic Submarine Deployment,” Navy.mil, 29 April 2011, www.navy.mil/submit/display.asp?story_id=60079.
11. CAPT Sam J. Tangredi, USN (Ret.), “Breaking the Antiaccess Wall.”
12. VADM Joseph Metcalf II, USN (Ret.), “Revolutions at Sea,” U.S. Naval Institute Proceedings, vol. 114, no. 1 (January 1988), 37.
13. John Reed, “China’s Carrier Killer Ballistic Missiles are Operational,” Defensetech, 28 December 2010, http://www.defensetech.org/2010/12/28/chinas-carrier-killer-ballistic-missiles-are-operational/.
14. “China Submarine Capabilities,” Center for Nonproliferation Studies, Nuclear Threat Initiative, 30 July 2015, http://www.nti.org/analysis/articles/china-submarine-capabilities/.
15. Norman Polmar and Michael Koffman, “Impressive Beneath the Waves,” U.S. Naval Institute Proceedings, vol. 143, no. 2 (February 2017), 64-65.
Arsenal ships are vulnerable
The arsenal ship, a canceled program, called for a large, minimally manned surface combatant designed for the sole purpose of cheaply and semi-stealthily delivering a massive arsenal of 768 Tomahawk cruise missiles. A spartan, behemoth surface vessel—such as one described by the notional design presented in Captain Sam Tangredi’s “Breaking the Antiaccess Wall”—would incur unacceptable risks.11 Tangredi identifies, yet does not adequately address, these issues that persist as dangers to the implementation of the design. They are likely the reasons that its original advocates—Vice Admiral Joseph Metcalf III and many other promoters—were unsuccessful in shifting procurement funding to develop the arsenal ship.12
To minimize cost and electronic detection, the modern arsenal ship concept would be fully reliant on Navy links for all long-range sensors and would rely on other assets for long-range surface-to-air missiles and supporting systems. Disregarding the potential significant risks within the cyber domain of having such an immense ordnance fully reliant on fleet network links, the arsenal ship would be exposed to surface-to-surface and air-to-surface missiles. It would use a large inventory of short-range point-defenses against antiship cruise missiles or aircraft, measures unlikely to be effective against the highly advanced cruise missiles of modern opponents. Tangredi admits that the arsenal ship—with its massive deck area covered in cruise missile vertical launch system modules—is particularly vulnerable to plunging fire. While he asserts that this is not so easy to achieve, China’s DF-21D “carrier-killer” missile capabilities, for instance, should not be underestimated.13 To effectively deploy an arsenal ship into a contested area such as the South China Sea, extra surface assets with sophisticated sensor and antiballistic missile capabilities would need to be pulled away from their other duties and put in harm’s way.
Within the antiaccess realm, the arsenal ship would also be particularly susceptible to threats beneath the waves. Large, slow-moving surface vessels—regardless of efforts to limit their radar cross sections or electronic emissions—will always be vulnerable to subsurface attack.14 Chinese submarine capabilities have been rapidly expanding in the past decade, and Russia has shown a renewed interest in increasing its submarine capabilities.15
With the growing emphasis on A2/AD capabilities by other nations, especially advance antiship cruise missiles and submarines, relying on an arsenal surface ship to break the antiaccess wall will become untenable.