Potential Chinese Anti-Ship Capabilities Between the First and Second Island Chains

Chinese Active Defense Layers (Office of Naval Intelligence graphic). Note that the range lines reflect where PLA aircraft and submarines might be expected to operate in wartime based on evidence to date. While PLA aircraft would be unlikely to fly further east from the second layer's line if U.S. and allied air coverage from bases along the Second Island Chain was strong, the same might not be true for PLAN SSNs. Also note that the maritime approaches to Luzon and the northern/central Ryukyus fall within the PLA's middle layer, and Taiwan and the southern Ryukyus within the inner layer.

There was a pretty lively debate in the comments to Chris Mclachlan’s post last month about the Combat Logistics Force. No one took issue with his observations that the CLF might be undersized for sustaining high-tempo forward U.S. Navy operations in the event of a major Sino-American war. Nor did anyone contest his argument that our replenishment ships lack the basic self-defense capabilities their Cold War-era predecessors carried. Instead, the debate focused on Chris’s assertion that CLF ships ought to be escorted during wartime by a small trans-oceanic surface combatant possessing medium-range anti-air and anti-submarine capabilities.

Needless to say, I agree with Chris’s view. Such an escort would be a necessary part of the overall combined arms solution set to protecting not only CLF assets but also the shipping that would surge reinforcements and materiel to embattled U.S. allies in East Asia, provide steady logistical sustainment to the U.S. and allied forces deployed to or based in those countries, and maintain the flow of vital maritime commerce to and from those countries. One rarely sees any of these four critical tasks acknowledged in discussions within the security studies community. I believe that represents a dangerous analytical oversight, as an American failure to adequately protect its own and its allies’ sea lines of communications in a war with China would be strategically disastrous. In today's post, I'm going to outline China's ability to threaten these lines in a notional major war. On Thursday, I'll outline how the U.S. and its allies might offset that threat.

Let’s first look at the strategic geography of the problem. The sea lanes in question pass through the waters between the First Island Chain and the line stretching from Hokkaido through the Bonins and Marianas to the Palaus (e.g,  the “Second Island Chain”). I’ve recently written about the PLAAF’s effective reach into the Western Pacific, and it’s been widely understood for years that late-generation PLAN submarines possess the technological capability to operate for several weeks in these waters before having to return to port. China would be hard-pressed to achieve localized sea control anywhere within this broad area; its own surface combatants and shipping would be just as vulnerable to attack. It wouldn’t need sea control, though, to achieve its probable campaign-level objectives of bogging down (or outright thwarting) an effective U.S. military response, or perhaps inflicting coercive economic pain upon one or more embattled American allies. The use of PLA submarines and strike aircraft to pressure U.S. and allied sea lines of communications would be entirely sufficient. And as Toshi Yoshihara and Martin Murphy point out in their article in the Summer ‘15 Naval War College Review, these kinds of PLA operations would be consistent with the Mao-derived maritime strategic theory of “sabotage warfare at sea,” albeit at a much greater distance from China’s shores than the theory originally conceived. Such operations have been widely discussed in Chinese strategic literature over the past two decades.[i]

It bears noting that our East Asian treaty allies like Japan, South Korea, and the Philippines would have inherent roles and responsibilities defending their sea lines of communication. Nevertheless, they probably would not be able to fulfill the mission entirely on their own given their maritime forces’ sizes and capabilities. There would probably need to be a geographical line of responsibility similar to what the U.S. and Great Britain worked out in the Atlantic during the Second World War; shipping protection west of the line would primarily be the ally’s responsibility, and the U.S. would be primarily responsible for shipping protection east of the line. Even so, the U.S. would probably still need to contribute escorts and supporting forces to assist the ally in protecting sea lanes that were within some threshold distance of the Chinese mainland. Shipping protection in the approaches to the Ryukyus, Taiwan, or western Luzon particularly come to mind.

While it is true that U.S. and allied forces could probably pressure the PLA’s ability to push submarines and aircraft through the Ryukyus’ various straits or the Luzon Strait in a war, they would probably not be able to fully seal those doors—at least not during the conflict’s early phases. The biggest reason for this would be the straits’ sheer proximity to the Chinese mainland: PLAAF/PLAN fighters would be readily able to escort their strike aircraft brethren out into the Western Pacific and back, not to mention threaten any U.S. or allied anti-submarine aircraft or surface combatants patrolling the straits. Granted, Chinese fighters would be exposed to any sea-based and mobile land-based area air defense systems covering the straits and their approaches. They might also be confronted by U.S. or allied fighters operating from austere island bases in the vicinity of the straits, or from aircraft carriers or land bases located at various distances “over the horizon” to the east. U.S. and allied defenders could additionally use any number of countertargeting tactics to reduce their susceptibility to attack.

However, even if the PLA could not damage or destroy many of these forces per raid, it could still take actions that effectively suppressed the straits “guardians.” One tactic might be to salvo land-attack or anti-radar missiles to distract the defenders or induce them to keep their “heads down” shortly before or during a straits transit. Another might be to damage runways or austere airstrips as possible in order to constrain the defenders’ air operations; repairs could take precious hours. Electronic attacks and tactical deception could also be used to screen transiting PLA aircraft and submarines. Periodic PLA suppression raids would neither be small undertakings nor without risk to the forces performing them, but they might be sustainable on an as-needed operational tempo for several weeks or months at minimum.

The other factor that would make it impossible to hermetically seal the First Island Chain barrier would be the difficulty in maintaining persistent U.S. or allied submarine coverage in all of the requisite straits. The U.S. presently has thirty-one non-special-purpose SSNs stationed in the Pacific; three are homeported in Guam and twenty in Pearl Harbor. Only a small number would be deployed at sea within quick steaming of the straits, though, unless timely indications and warning of an impending crisis or conflict were received and then acted upon by U.S. leaders. The high-readiness Guam boats would be able to arrive on scene fairly rapidly once sortied, but it would take several more days for them to be reinforced by Pearl Harbor boats—not all of which might be immediately surgeable due to inter-deployment maintenance. Japan could surely contribute a number of its sixteen modern SSs in active service, but again not all of them might be surge-ready at any given time. And while the U.S. and Japanese fleets will be receiving additional boats over the coming decade, it will not be at a rate and scale that would dramatically change the straits coverage math. Hypothetical seabed-mounted sonar arrays in these straits or their approaches might help improve these odds by cueing available U.S. or allied submarines (or other anti-submarine forces) to a PLA submarine transit. The probability of a friendly submarine intercepting a PLA submarine detected this way, though, would depend upon the time between when the cue was broadcast and when it was received by the friendly sub, how the friendly sub's effective sonar ranges in those waters affected its ability to redetect the trespasser, and whether the friendly sub could cover the distance from its starting point to have a chance at redetection before the cueing data "aged out." More than one boat might be required to cover any particular strait with a certain margin of confidence; this would be especially true for the wider straits. Nor would anti-submarine patrols in the straits be the two sub fleets’ sole mission at the beginning of a major war: there would be equal if not greater demands for land-attack strikes, anti-submarine and anti-surface patrols inside the First Island Chain, anti-submarine patrols between the two island chain lines, special forces insertion/extraction, and far-forward intelligence/surveillance/reconnaissance. U.S. and Japanese submarine coverage of the straits simply could not be absolute.

It would be excellent if U.S. and allied forces could attrite the PLA forces making or supporting straits transits by a few percent each time without suffering equivalent attrition; the cumulative effects on the PLA’s overall warmaking capacity would be significant. But it would take weeks if not months for those effects to really show. That’s why the ability to logistically sustain the land-based forces waging the protracted frontline fight would be so crucial to U.S. war strategy. If the PLA were to inflict enough pressure on these logistical flows, the barrier defense would eventually wither on the vine.

It’s also important to remember that this imperfect barrier would only function in an open war—not during a crisis. Any PLAN submarines sortied prior to the outbreak of open hostilities could in theory patrol between the two island chain lines for campaign-significant amounts of time before having to hazard a trip back through the First Island Chain gauntlet. Modern PLAN SSNs like the Type 093 and its Type 095 follow-on would have an obvious endurance advantage over Air-Independent Propulsion (AIP) boats like the Type 041, but even the latter could probably remain underway for a few weeks before requiring a return to port. During that time, the mere fact that PLAN submarines were unlocated in the Western Pacific would undoubtedly affect U.S. operations (and tempo) in theater. The Royal Navy’s experience coping with a single unlocated Argentine submarine during the Falklands War is instructive on that point.

It would not take many PLAN submarines to generate such effects. For instance, let’s assume that the PLAN allocated its Type 041s, Type 093s, and Type 095s for war-opening operations between the two island chain lines while simultaneously holding its Type 035A/B/G, Type 039, and Kilo-class diesel-electric boats back for operations within the East and South China Seas. Let’s also assume China had its planned twenty Type 041s and five Type 093s in commission, plus perhaps five Type 095s as well, when a conflict erupted. Lastly, let’s assume that these boats’ material conditions of readiness were high enough to sortie two-thirds of them into the Western Pacific as the crisis phase peaked. Thirteen AIP boats and six SSNs might not seem like a lot within such a broad expanse. However, as Julian Corbett pointed out a century ago, the most “fertile” areas for hunting ships are “the terminals of departure and destination where trade tends to be crowded, and in a secondary degree the focal points where, owing to the conformation of the land, trade tends to converge.”[ii] If the PLAN followed Corbett’s logic, it might position its submarines in waters the U.S. and its allies would have to traverse to access (or break out of) selected major ports along the First Island Chain during the war’s first weeks. Or it might assign those duties to the Type 041s and deploy its SSNs in the waters just west of the Marianas that shipping from Guam, Hawaii, or the continental U.S. might seek to traverse. Or if the Chinese Ocean Surveillance System’s (COSS) coverage between the island chain lines remained adequate after the war started, China might try to steer its SSNs into mid-transit contact with U.S. or allied shipping.[iii] What’s more, the lingering effects of a PLA conventional first strike against major U.S. and Japanese bases in the Japanese home islands and Okinawa, subsequent PLA suppression operations against U.S. or allied straits-guarding forces along the Ryukyus-Luzon line, and in-theater U.S. and allied anti-submarine-capable forces’ sheer combat load prior to the arrival of reinforcements from the U.S. suggest that at least some PLAN submarines could complete at least one full cycle from their patrol areas to port for replenishment and then back into the Western Pacific before the “happy time” window began to close. This would especially be true for PLAN submarines patrolling the approaches to the Ryukyus, Taiwan, or Luzon.

Add the PLAAF/PLAN strike aircraft threat back into the mix and it should be apparent that U.S. and allied use of the Western Pacific’s surface between the two island chain lines would likely be opposed early in a notional war. The key variables driving China’s anti-shipping potential within these waters would be COSS’s ability to provide PLA aircraft and submarines with actionable targeting cues despite intense U.S. (and possibly allied) efforts to degrade and deceive this system-of-systems, the PLA’s ability to push those forces through contested First Island Chain straits when and where needed, and the operational range and endurance of those forces. 

The views expressed herein are solely those of the author and are presented in his personal capacity. They do not reflect the official positions of Systems Planning and Analysis, and to the author’s knowledge do not reflect the policies or positions of the U.S. Department of Defense, any U.S. armed service, or any other U.S. Government agency.

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[i] For instance, see Chapter 3 of Roger Cliff, et al. “Entering the Dragon’s Lair: Chinese Antiaccess Strategies and Their Implications for the United States.” (Santa Monica, CA: RAND Corporation, 2007).

[ii] Julian Corbett. Principles of Maritime Strategy. (Mineola, NY: Dover Publications, 2004), 263.

[iii] For more detail on COSS, see Section 2 of Jonathan F. Solomon. “Defending the Fleet from China’s Anti-ship Ballistic Missile: Naval Deception’s Roles in Sea-Based Missile Defense.” (Master’s Thesis, Georgetown University, 2011).

The Navy’s Combat Logistics Force and the 21st Century Threat Environment

Then-USS Arctic (AOE-8), Undated. (U.S. Navy Photo)
Note NATO Sea Sparrow launcher, forward Close-In Weapons System mount, and deckhouse-mounted SLQ-32(V)3.

Jon’s note: I’d like to introduce a new navalist voice, Chris Mclachlan. Although he’s at the start of his professional career, I’ve been thoroughly impressed by his maritime strategic insight over the several months he and I have been discussing such topics. When he suggested to me that he wanted to write about the logistical aspects of fighting a major war at sea in the Western Pacific, I lobbied hard for him to allow me to publish his work here at ID. I think you’ll see why.

On July 31, 2014, the House Armed Service Committee Subcommittee on Seapower and Force Projections convened a hearing to discuss Sealift Force Assessment. One concern expressed at the hearing was by Rep. J. Randy Forbes, the committee’s chairman, regarding the ability of the Navy’s Combat Logistics Force (CLF) to conduct its mission in a contested environment. Without increasing the CLF’s current level of capabilities to survive in such environments as well as shuttle fuel, ammunition, and stores to forward naval forces, the U.S. Navy will not be able to meet emerging threats in the Asia-Pacific. Currently, there has been little internal or public discussion on the ability of the CLF to sustain the operational tempo demanded of the Navy in a major conflict, let alone do so within a combat zone.

The current logistics fleet is derived from the 1992 “. . . From the Sea” and 1994 “Forward. . . From the Sea” strategic concept documents.  These concepts were based on the premise of general U.S. command of the open oceans, which meant that the Navy could focus much of its efforts in the littorals. The Navy’s ability to obtain virtually de facto sea control in the post-Cold War era allowed it to project power from close to adversaries’ coastlines and then be resupplied from sanctuaries these adversaries simply could not touch. It follows that the Navy did not foresee a need to escort its logistics ships to and from these underway replenishment locations. Nor did it assess that the logistics ships retained the need to defend themselves against missile or torpedo attacks. The Navy’s decision to replace the Oliver Hazard Perry-class guided missile frigates with the Littoral Combat Ship (LCS) was greatly informed by this view.

Potential adversaries’ advancing capabilities for denying access and limiting freedom of maneuver in contested maritime areas have effectively negated the underlying premises of the Navy’s post-Cold War strategic concepts. In particular, China’s inability to seriously challenge the U.S. Navy during the 1996 Taiwan Straits Crisis persuaded it to develop capabilities to disrupt the U.S.’s ability to intervene militarily against Beijing’s interests in East Asia. Submarines, mines, land-based fighter and bomber aircraft, land-based strike missiles, advanced air defense systems are the major elements of China’s capabilities for denying maritime access to the East Asian theater. The employment of many of these weapons are cued by networked wide-area surveillance/reconnaissance systems located on Chinese soil, in the air, at sea, and in space.

The new environment poses a significant danger to U.S. naval operations. With a considerable forward presence in the Asia-Pacific, the U.S. Navy must sustain operations over what is often referred to as the “tyranny of distance.” Once in theater, if warships are unable to replenish at sea, they must then return to a friendly port. The process of transiting to a port, replenishing and then returning to a forward operating area may take days or even weeks. Forward ports and naval facilities are also becoming increasingly vulnerable to theater-range precision guided munitions. Such delays and risks would be untenable in a major conflict.

And yet, no moves have been made to arm the logistics fleet with point defense weaponry. Further threatening the CLF’s ability to operate in opposed environments is the Navy’s declining surface combatant force structure. The final retirement of all the Navy’s FFGs this year will have a major impact on the defensibility of forward- deployed ships’ logistical support chains. As previously noted, the LCS is incapable in its current and planned configurations to assume the FFGs’ Cold War-era role screening logistics ships’ movements in contested waters. The lack of  small surface combatants with medium range air defense and anti-submarine capabilities  means that vital DDGs would be utilized as CLF escorts instead of being utilized in carrier battlegroups or surface action groups. The forthcoming LCS-derived frigate will address only the anti-submarine portion of this capability gap.

In addition to the loss of the FFG escorts, the retirement of all of the Navy’s T-AOEs will further amplify the fleet’s combat logistics dilemma. T-AOEs are the most important logistic ship in the Navy’s inventory as the ship provides a “one stop shop” for combatants as it carries marine fuel, aviation fuel, dry stores, and munitions. Furthermore, it is the only replenishment ship that is fast enough to keep up with a carrier battle group and thus remain within its protective air, surface, and subsurface defenses. Due to budgetary constraints the Navy is planning on putting two T-AOEs in reduced status while keeping two in service. Without the T-AOEs the Navy is left with the less capable but more numerous T-AO and T-AKEs which supply fuel and ammunition/dry stores respectively. Both the T-AOs and T-AKEs are incapable of matching the speed of the carrier battle group and require more time to replenish combatants. Furthermore, it is not clear the Navy and the Military Sealift Command have enough of these ships to sustain a high operational tempo in a major conflict, or how severely CLF losses  would degrade this tempo. This represents a crucial area for war-gaming as well as campaign analysis.

Although the current logistics model was adequate for a post-Cold War world in which the U.S. Navy maintained essentially-uncontested command over the world’s oceans, potential adversaries’ development of advanced maritime denial capabilities demands a new approach. Fleet structure and composition is not properly aligned to support forward positioned surface combatants in a contested environment for extended periods of time. Ensuring timely and consistent logistics support to these combatants is central to the U.S. Navy ensuring American maritime supremacy. The presence of forward forces is critical to U.S. security.  Logistics ships must receive basic self-defense capabilities as well as be provided sufficient escort support for their transits through and operations within opposed areas. The Navy also ought to retain logistics ships that are capable of operating as part of battle groups: in active service if possible, and in ready reserve if necessary. Failing to do these things could cost the Navy—and the nation—dearly in the event of a future war.

Chris Mclachlan currently works as a defense contractor. He recently spent time working on defense issues at the House of Representatives. The views presented in this article are his own.

Chinese Maritime Strike Capabilities and the Fragility of U.S. Sea Lines of Communication Along the First Island Chain

On 30 March, the People’s Liberation Air Force conducted a long-range bomber exercise sortie into the northern half of the Luzon Strait. It isn’t clear from the media reporting whether the bombers flew further east into the open Western Pacific as part of the drill. The pictures accompanying the PLA’s press announcement on the exercise suggest H-6K bombers were employed—essentially a modernized version of the 1950s-era Soviet Tu-16 Badger. H-6K’s combat range is rumored to be approximately 1900 nautical miles. When one adds on an H-6K’s YJ-62 subsonic or YJ-12 supersonic ASCMs, the maximum anti-ship striking reach extends by roughly 180 or 250 nautical miles respectively.

In effect, and assuming an airfield relatively close to China’s coast, the PLAAF demonstrated a H-6K maritime strike at approximately 20% of the bomber’s notional maximum combat radius. This reach may seem underwhelming at first glance. However, if one were to draw that 20% as an arc extending outward along China’s entire coastline, then tack on the YJ-12’s assumed range, the entirety of the maritime approaches to Taiwan, the Ryukyus, the northern and western coasts of Luzon, the west coast of Kyushu, and the southern coast of South Korea lie inside the perimeter with plenty of standoff room.  20% can be more than enough.

It is quite possible that the effective range of those missiles against a given ship or surface grouping under wartime conditions would be significantly less than the advertised maximum range. Nevertheless, U.S. commanders would not only have to take the missiles’ maximum theoretical range into consideration when designing campaigns and operations, but would also have to account for the H-6Ks’ maximum theoretical range. Not to mention J-11 fighters carrying YJ-12s. Rest assured that these kinds of risk calculations are very much on the mind of U.S. treaty allies in the region.

The U.S. Navy has not faced an analogous “blue water” air threat since the Cold War days of Bears, Badgers, and Backfires. These Soviet bombers were not tasked with pressuring the trans-Atlantic flow of reinforcements and supplies to Western Europe, however (and Badger couldn’t reach far enough south in any event). Nor were there Soviet fighters capable of escorting them all the way out to those sea lanes. The principal theoretical threat to these flows was therefore Soviet submarines (even though that really wasn’t their primary mission either), which in turn drove design requirements for convoy escorts like the Knox and Perry-class frigates.

As alluded to above, Western Pacific geography presents a completely different story. Let’s use the Ryukyus as an example. It is highly desirable to deploy U.S. air and missile defense systems, Japanese anti-ship cruise missile batteries, and U.S. and Japanese fighters capable of dispersed operations from ad hoc airfields to these islands in order to pressure Chinese air and naval surface forces’ wartime abilities to break out into the Western Pacific. These systems are also highly important to complicating PLA air and naval surface operations within the East China Sea, as well as defending the Ryukyus from direct PLA strikes or expeditionary assaults. They might contribute significantly to bogging down a Chinese war-opening offensive long enough to prevent a fait accompli under certain circumstances.

How, though, will these forces be logistically sustained if PLAAF fighters can use their numerical superiority to disrupt or deny U.S. airlift efforts, and the striking reach of its H-6Ks and J-11s to pressure U.S. sealift efforts? How will transport aircraft and convoyed shipping be able to unload their cargoes if the requisite airfields and seaports have been subjected to debilitating air and missile bombardments (or mine-laying), or if PLA forces can direct fires against these facilities on short notice? Now let’s take this one step further: how will the U.S. and Japan protect the flow of basic economic sustenance to the islands’ civilian populations under such conditions? Also bear in mind that unlike the Cold War-era Soviet maritime bomber threat, H-6Ks can be escorted thousands of miles out to sea by J-11s (and many other PLAAF fighters for overwater missions closer to home), thereby providing a modicum of protection from U.S. and Japanese fighters. Now factor PLAN submarine capabilities into the mix. The difficulty of these challenges should be apparent. What’s more, the same challenges would apply in conflicts involving the Philippines, South Korea, and of course Taiwan.

This is why I say land-based forces positioned along the First Island Chain can “pressure” PLAAF and PLAN breakouts through the First Island Chain, not block them altogether. “Pressuring” them is very useful in that it can support friendly naval forces and convoys operating in the open ocean by providing some warning of an outbound raid as well as knocking out some of the raiders during both the outbound and inbound legs. It also would entice China to expend a disproportionate effort trying to locate and suppress the ‘gatekeepers’ early in a major war. Similar logic applies to the use of such forces for pressuring Chinese use of the East or South China Seas in the vicinity of allied islands, including the direct defense of the islands themselves.

As I’ve noted before, unless the maritime lines of communication to these islands are kept open, the maritime denial forces on them essentially become “wasting assets” if not sacrificial speedbumps. Yes, ammunition and food can be stockpiled to allow such forces to hold out for protracted periods—if such a foresighted step is taken during peacetime. And even if it is, the stockpile will only last for a finite period. Munitions expenditures will likely be higher than anticipated in peacetime planning. There will be combat losses and a corresponding need (or at least desire) to funnel in replacements. Can replenishment and reinforcement be done with confidence under the circumstances I’ve outlined?

Nor does any of this even begin to cover the islands’ populations’ needs for basic staples like food, medical supplies, fuel, whatever external trade can be sustained, and so on. Imagine the political pressures upon an embattled ally’s government—and thereby upon U.S. political leadership—to break a Chinese maritime siege. Imagine the political and strategic consequences if the siege could not be broken. This could, in fact, be a principal Chinese objective in a notional conflict of limited aims.

Such issues are seldom raised in public proposals of or commentaries on strategic concepts for deterring—and if necessary waging—a war against Chinese aggression in East Asia. There are a few indications that this fog may be lifting, though. I certainly hope that’s the case, as any strategic concept for East Asia that doesn’t address these questions is seriously incomplete.

It’s important to keep in mind that the challenges I’ve described are hardly insurmountable. Here’s a non-exhaustive list of measures that could contribute towards solutions:

• Contingency plans could emphasize offensive and defensive operations aimed at protecting critical maritime lines of communication to allied territories and forward forces.

•  Contingency plans could also incorporate entire sets of sequential or parallel operations in the physical, electromagnetic, cyber, and space domains to temporarily if not permanently degrade the surveillance-reconnaissance apparatus that PLA maritime strike aircraft, submarines, surface groups, and land-based missiles depend upon for over-the-horizon targeting cues.

• Combined arms operating concepts and tactics could be developed for screening convoys from air and submarine attack using existing (or forthcoming) platforms and systems.

• New logistics concepts for using existing or forthcoming transport platforms to keep dispersed forces supplied from afar when large airfields and seaports are unavailable.

• Medium-range air defense missiles could be added to the forthcoming LCS-derived frigate so that it could perform convoy escort in high air threat environments.

• A long-legged large weapons payload fighter (F/A-XX?) and a wide-area anti-submarine aircraft could be added to the future carrier air wing.

Bottom line: land-based maritime denial forces in the First Island Chain can do many things that complement naval battleforces at the campaign-level. They cannot substitute for them. 

The views expressed herein are solely those of the author and are presented in his personal capacity. They do not reflect the official positions of Systems Planning and Analysis, and to the author’s knowledge do not reflect the policies or positions of the U.S. Department of Defense, any U.S. armed service, or any other U.S. Government agency.