Are Our Boomers Vulnerable?

D

This past June, the ballistic missile submarine Ohio (SSBN-726) went to sea for the first time on trials. When she and her forthcoming Trident-armed sisters are commissioned, the U. S. strategic deterrent will be strengthened at a time when the other two legs of the triad— manned bombers and land-based missiles—are considered increasingly vulnerable to Soviet defenses. Isn't there cause to wonder also about advances in Soviet antisubmarine warfare and their effect on the missile-armed “boomers”?

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uring the past few years, with the increa^sltlr theoretical vulnerability of land-based missil^ the importance of U. S. sea-launched ballistic mb siles has grown. However, Dr. William J. P^err'j former Undersecretary of Defense for Research a*¹ Engineering, stated the following on 24 April l9j^' “Submarines are invisible today. By the 1999 ' whether we will have learned a way or whetn ^ the Soviets will have learned a way of making 9] oceans transparent is precisely the issue. judgment is that we ourselves will be able to d tect and locate Soviet submarines at sea at m period. I have no reason to believe that the viets will not be able to do a similar thing- Any assessment of the survivability of U. S. ^se^ based strategic forces must logically be based analysis of the Soviet antisubmarine warfare (A^ -_c program and particularly its implications for ball*^s

^'ssile-carrying submarines. While much of the Serial on Soviet efforts in this area is classified, ^a §reat deal of information also appears in open ^s°urces. The purpose of this article is to attempt to ^^lece together this information and to arrive at some ^elusions concerning the strategic implications of ^ae Soviet ASW program.

Geography: While the Soviet Union possesses the I °^rld’s longest coastline, it is actually all but land- ^^cked. Russia’s few available ports are poorly , ^aced and lack convenient outlets to the deep ocean ^as>ns. The Soviets’ resulting difficulty in projecting ^ufficient ASW forces into deep waters is crucial •nee America’s geographic position—along with ^e locations of its allies—allows the U. S. Navy to I P^erate ballistic missile submarines (SSBNs) in ^rge portions of these waters.

The Soviet ASW Program: Soviet naval declara­tory policy since 1964 has emphasized blunting nu­clear attacks from sea-based ballistic missiles. Within this context, the Soviets have two concerns: (1) limiting damage to their homeland and military forces and (2) bringing any conflict to a favorable conclusion by degrading the American strategic re­serve. However, some Soviet statements made since the late 1960s have indicated that strategic ASW may no longer occupy the primary position it once did, largely because of technical and oper­ational difficulties. While the Soviets are probably still interested in countering American missile sub­marines, they are not likely to achieve a solution in the near future.

The Soviets are conducting a broad-based effort to develop a number of systems which might prove useful in conducting strategic ASW. The following is a survey of that effort:

► Sea-Based Surveillance Systems. It has been re­ported that the Soviets have installed a hydrophone barrier stretching from the Kola Peninsula to Spits­bergen, protecting the approaches to the Barents Sea. It is also likely that Soviet fixed acoustic in­stallations in the Kurile Islands guard the entrances to the Sea of Okhotsk. They have employed bottom- anchored acoustic devices, essentially large sono- buoys, which are feasible in some waters not con­tiguous to the Soviet Union, since these systems can be laid covertly and read by passing submarines, aircraft, and surface ships. Devices of this type have been deployed off Norway and Great Britain and probably have been installed in parts of the North Pacific. There have also been indications that similar systems may be laid in the Canary Basin off Northwest Africa, a potential deployment area for Poseidon-armed submarines. In the future, similar acoustic devices and perhaps sensors designed to detect extremely low frequency (ELF) submarine communications might be emplaced in other waters, particularly at key geographic choke points.

Since the early 1960s, Soviet intelligence gath­ering ships (AGIs) equipped to detect and analyze radioelectric and electromagnetic signals have been deployed in the immediate vicinity or within easy reach of American ballistic missile submarine bases. While this practice does not enable the Russians to discern where the submarines actually go, by tuning into U. S. communications, AGIs probably gather valuable information on deployment schedules. On occasion, Soviet nuclear attack submarines oper­ating in conjunction with these ships have attempted to trail American submarines leaving port.

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► Nuclear Attack Submarines. The Soviet Union’s nuclear attack submarine force is currently inade­quate to present a threat to American ballistic mis­sile submarines except perhaps in waters near the U.S.S.R. Recent developments in Soviet propul­sion and hull technology could help improve their

submarine ASW capabilities. Two to three ships of the new “Alfa” class are reported on active duty with five additional ships under construction. On the basis of her speed, deep-diving capability, and improved active sonar suite, this submarine could have a greater technical capability than her prede­cessors to trail American SSBNs as well as to con­duct ASW operations in general.

► Land-Based Aircraft. Soviet Naval Aviation forces for ASW operations appear to be quite lim­ited, especially for conducting operations beyond contiguous waters without forward bases. The IL- 38, an aircraft similar in appearance but not quality to the American P-3, has an operational radius of little more than 1,500 nautical miles and operates widely over the Barents and Norwegian seas as well as the North Pacific. About 60 are believed opera­tional with Soviet naval units. The Beriev M-12, 80 of which are on active duty, is an amphibian with an operational radius of approximately 1,000 naut­ical miles. The only Soviet aircraft with sufficient range to conduct ASW operations in the deep ocean basins is the “Bear F,” a variant of the large tur­boprop strategic bomber, which has an operational radius of 3,000 to 4,000 nautical miles. Approxi-

Since the early 1960s, Soviet intelligence gathering ships such as this AGI of the “Mirnyy” class have been deployed in an effort to detect and analyze electronic signals from U. S. submarines.

mately 30-40 units are reported on active duty,³ number wholly inadequate for the task at hand. Pro­curement of new fixed-wing ASW aircraft seems to have halted in 1976, although “Bears” have bee" converted to perform the ASW mission at the rate of approximately five per year.

► Surface Skimmers. Since 1965, the Soviets have conducted an important research and development program on wing-in-ground (WIG) effect vehicles' a form of surface effect ship that resembles a flyin? boat. Soviet statements have indicated that long- range WIG effect vehicles may be used in ASW are³ search operations. While some analysts believed that such vehicles would join the Soviet Navy in the late 1970s, none has become operational, perhap⁵ indicating that some technical difficulties have ari­sen or that the program is no longer an important priority.

► ASW Mines. Soviet naval mines can be divide^ into four major categories: moored, seabed, flo³'" ing, and nuclear. Many of them are suitable for ham­pering submarine movement from port or through important geographic choke points. These include several new deep-water influence mines, possihh detonated by a submarine’s magnetic signature' which enable them to block key geographic point⁵ previously considered incapable of being mined- Delivery platforms include aircraft, surface com­batants, and submarines. While the sophisticatin'¹ of Soviet mines may be sufficient to threaten Amer­ican ballistic missile submarines and impose P^' chological constraints in wartime, delivery to are³⁵ far from the Soviet Union could prove to be e* tremely difficult.

■ surface and submerged wake effects produced passage of a submarine through water; and .signatures generated by submarine communi- ^fi°n systems, such as towed buoys and trailing

^ Acoustic ASW Technology. The United States has ^always placed a great deal of emphasis on the pro­curement of quiet submarines, so quiet in fact that ^advanced American ASW systems have had great difficulty in tracking American SSBNs in exercises. The combination of quiet American submarines and ^a relatively unsophisticated Soviet signal processing ^CaPability has rendered Soviet passive detection ^sterns relatively ineffective and has forced the Asians to invest heavily in active acoustic sensors ^CaPable of detecting self-generated sound bounced jjff an enemy submarine. Active acoustic sensors, nature, have much shorter ranges than passive ^s°nars. As a result, Soviet ASW platforms can track ^and attack enemy submarines only at fairly short ^Pges.

* ^ong-Range Ballistic Missiles. There have been judications for a number of years that the Soviets ^aave seriously considered the potential role of all j^Pes of ballistic missiles in crucial naval operations. ⁿ addition to a special casing to permit reentry ve- ^a'des to withstand the stress of impact with the °^Cean’s surface and to detonate underwater, the ^ssile must either (1) be equipped with a terminal ^idance system for in-flight course corrections to plow for submarine movement between initial de­letion and the arrival of the missile, or (2) carry a ^arge number of powerful warheads able to lay down ^atl effective barrage over an area large enough to .^e into account target movement.

Afew Technologies. In 1978, Rear Admiral Sumner pnapiro. Director of Naval Intelligence, remarked, ,'^Ve know the Soviets are engaged in a very exten- ?^lve research and development effort, particularly ^1,1 Hie nonacoustic realm.” As a result, deployed jj°Pacoustic sensors, particularly magnetic anomaly I .fetors, seem to be comparable to those of the P'ted States. It has also been reported that Soviet [^acoustic research and development programs be as much as five to ten years ahead of similar j^Perican programs. The broad nature of the Soviet ^acoustic program deserves further examination. . ^evelopment of nonacoustic technology involves ^aePtifying three broad categories of submarine sig- ^aiures: the magnetic signature of a submarine hull;

While nonacoustic detection systems could prove useful when mounted on a variety of platforms, their maximum potential could be most effectively ex­ploited when mounted on satellites. In 1969, Rear Admiral Levering Smith, then Director of the Navy Strategic Systems Project, stated that the Russians did not have an operational ASW satellite capability. Since then, while there have been no official state­ments on Soviet satellite systems, there has been no evidence that they have overcome the enormous technical problems in developing such a system. Included among such problems are a high false- alarm rate and difficulty in detecting submarines not operating near the ocean’s surface.

It is conceivable that the Russians do have some satellite systems in orbit with limited applicability to the strategic ASW mission. For instance, elec­tronic ferret satellites could be capable of inter­cepting an American submarine’s communications and fixing her position. However, it is important to note that these submarines maintain silence for much if not all of their time at sea. Also, Soviet

early warning satellites equipped with infrared sen­sors might fix the position of a submarine firing her missiles in a nuclear war and bring down counter­battery fire on her.

Operational Assessment: The Soviet Union’s ability to concentrate sufficient ASW capabilities to present a potential threat to American ballistic mis­sile submarines is severely limited. The only waters in which the Russians might present a threat to American submarines, particularly the Sea of Okhotsk and the Barents Sea, lie contiguous or near to the Soviet Union. The perceived threat posed by Soviet ASW forces in these areas is relatively high since it is in these waters that the main Soviet ca­pabilities are concentrated in peacetime and where they are likely to be found in wartime. Also, the Norwegian Sea, the eastern Mediterranean, and the Sea of Japan are likely to be perceived as increas­ingly hazardous SSBN operating areas largely be­cause of the expansion of Soviet naval operations in these waters. This could have some impact on the perceived ability of SSBNs to perform certain specific missions. For example, a missile-carrying submarine can move closer to enemy shores, thereby reducing warning time and simultaneously increasing the accuracy of her missiles. The mission could become more difficult if the chances of de­tection are perceived to be great.

However, it is important to distinguish between the perceived threat and the conduct of actual op­erations against any American submarines. There

have been reports of American nuclear attack su^ marines occasionally slipping in and out of the Ba^f ents Sea and even Soviet ports without being covered. It seems reasonable to assume American SSBNs, if need be, could also avoid o^e tection in these hazardous waters and in the p^r0* imity of Soviet ASW forces in other areas. Secon • maintaining track of a submarine once contact ¹ made might also prove difficult, given Soviet r^{e 1} ance on active sonar. Based on U. S. Fleet exercis^e and projected trends in Soviet ASW technology new Trident submarines are supposed to have su ficient speed to make them highly survivable *ⁿ the next century, while Poseidon-armed SSBNs a likely to have sufficient speed until the 1990s.

^nally, American acoustic countermeasures are de­igned to deal effectively with the Soviet active ^sonar threat.

In any case, the importance of waters contiguous ^lo or near the Soviet Union as potential operating ^areas for U. S. ballistic missile submarines has de­ceased over the past two decades at the same time ^as Soviet ASW capabilities have gradually im­proved. Since the deployment of the first American ^SSBN in 1960, steadily increasing sea-launched bal- ‘istic missile ranges have enabled U. S. sea-based strategic forces to expand potential patrol areas and |° “stand off' from potential targets in the Soviet ynion at greater distances. In spite of the decreasing "Pportance of the waters relatively close to the “•S.S.R. for American missile-carrying subma- ^r'ⁿes, it is important to note they should still have s°me relevance as SSBN patrol areas until at least ^ljie early 1990s. Waters such as the Norwegian Sea, ^ae Mediterranean, and those near the Soviet Union ^VV|H continue to account for a significant percentage

the total patrol areas available to the Poseidon- ^arrned SSBNs.

fn light of this evolving situation, the Poseidon ^snips are likely to bear the brunt of many of the Projected improvements in Soviet ASW capabili- '^es- According to Dr. David E. Mann, Assistant . ^ecretary of the Navy for Research and Engineer-

“The Soviets are expected to have more long- ^range patrol aircraft, more surface ships with im­proved ASW capabilities, improved acoustic sen­iors and possibly towed-array sonars. . . . These improvements will give the Soviets better tech- ⁿ'cal capabilities to detect, track and attack sub­marines operating near the USSR, who are in con­fined waters or are transiting chokepoints." fi^e U. S. Navy has been concerned for some time _t^b°ut potential vulnerabilities, as evidenced by con- ^lnUed efforts to procure the extremely low fre- fijjency (ELF) communications system which would ^ev>ate the requirement to operate near the sur­face. The technology for the detection of a sub­marine’s trailing wire and towed buoy is well doc­umented, and the Soviets are known to be conducting research into potentially useful non­acoustic sensors. While there are no operational Soviet systems of this type known to be deployed today, based on present technological evidence, even aircraft with moderate-range nonacoustic sen­sors could present a potential future threat. How­ever, it should be noted that this concern —according to testimony in 1977 by Vice Admiral Robert Y. Kaufman, then Director of C³ Programs in OpNav—is limited to the possibility of “a chance one or two sinkings” in wartime.

Clearly, the crucial question in evaluating Soviet strategic ASW capabilities is the effectiveness of forces available for deep ocean basin operations since these waters have and will continue to acquire increasing importance as SSBN deployment areas. At present. Soviet ASW forces available for peace­time and wartime operations include an inadequate number of submarines, aircraft, surface vessels, and intelligence-gathering ships. This shortage is enor­mously magnified by the absence of an area sur­veillance system which might give the Soviets some idea of the approximate locations of American SSBNs on patrol and enable them to concentrate their limited forces. Moreover, the extensive U. S. surveillance systems covering potential American SSBN patrol areas provide the submarines with con­tinuous information on the whereabouts of Soviet naval forces, thus enabling them to take evasive maneuvers if necessary.

The key to the Soviets establishing an improved strategic ASW posture in the future would seem to depend on how successful they are in detecting and tracking American SSBNs in the deep ocean basins. Two potential approaches to such a capability, not mutually exclusive, can be postulated.

► Trailing. This would involve peacetime opera­tions designed to follow ballistic missile submarines throughout their patrols. The most practical method to initiate a trail is simply to wait at base exits or at relatively narrow geographic choke points for these ships. Nuclear attack submarines, because of their speed and endurance, are considered the most effective ASW platforms for trailing. However, even if the new “Alfa” class is procured in sufficient numbers and is employed in trailing attempts, other factors come into play which would probably serve to curtail any potential threat posed by these sub­marines as well as any other Soviet attack subma­rines. Geography is a powerful constraint on the Soviets’ ability to concentrate capabilities outside of American submarine base exits. The U. S. Navy recently ceased strategic operations at all of its overseas submarine bases except at Holy Loch, Scotland. The great distances between Soviet sub-

marine and American SSBN bases make it ex­tremely difficult for the Russians to attempt trailing on anything more than an occasional basis. This difficulty in attempting to station attack submarines near base exits is compounded by the generally low peacetime Soviet submarine deployment rate of 10­15%.

There has been some speculation that the possible availability of naval bases in Cuba in close proximity to the new ballistic missile submarine base at Kings Bay, Georgia, might help change this situation. However, in 1977 Rear Admiral Albert L. Kelln, then director of the Strategic Submarine Division in the office of the Chief of Naval Operations, stated in response to questioning by the Senate Armed Services Committee:

“If you are asking could the Soviets stage a threat in peacetime out of Cuba, the answer is yes. Would it cause us some due concern? I think that with the assets we have at hand we would be able to handle that problem quite adequately.” This points out another problem the Soviets face in attempting to mount any trailing operations; any submarines they do position outside of American base exits are not likely to be there without the knowledge of the appropriate U. S. military offi­cials. Soviet submarines leaving their home ports are subject to almost continuous surveillance by American and allied ASW forces, surveillance which is likely to become increasingly effective dur­ing the next decade, especially in the deep ocean basins through which Soviet submarines must pass to reach SSBN bases in the continental United States. Consequently, American ASW forces are in a position to initiate the appropriate countermea­sures designed to prevent Soviet boats from suc­cessfully initiating trailing operations.

► Area Search. Basically, this would involve utiliz­ing a long-range area surveillance system to provide initial target information for appropriate ASW plat­forms. For example, the U. S. sound surveillance system (SOSUS) can determine the position of So­viet submarines in many areas of the world to within 50 nautical miles, allowing ASW forces to conduct follow-up operations. The area search threat seems to be the ASW strategy which most concerns U. S. defense planners. Therefore, the new Trident-armed submarines have been configured to address this concern.

It seems to have become quite clear to the Rus­sians that because of their geographic, technical, and operational ASW problems, they would have to construct an open-ocean area search system dif­ferent from that of the United States. One Soviet option which has been the repeated subject of spec­ulation would be a satellite-based, nonacoustic de­tection system providing near or real-time target data to land-based installations. The key technical issue is whether a space system can be developed to the point at which it would be able to provide target data with sufficient reliability. This would entail overcoming the substantial technical prob­lems already mentioned. In addition, an ASW sat­ellite system probably would have to be able to dis­tinguish between different types of submarines in order to identify those which carry ballistic missiles. Theoretically, this might be possible in some cases since the 18,700-ton Tridents are likely to generate a more distinct set of nonacoustic signatures than other submarines. Distinguishing between smaller submarines approximately equal in size could prove very difficult. An alternative might be for some sea- based system, either AGIs or submarines, to pro^­vide initial identification after encountering aⁿ American SSBN; confirmation would be by the sat­ellite system.

The development and deployment of a satell»^te detection system would represent an enormous technical feat and would be a definite improvement over current Soviet deep-ocean basin surveillance capabilities. Although a space system would cer­tainly create a more hazardous operating environ­ment for American submarines, this is not to say that it would render sea-based strategic forces vul­nerable to attack, especially in view of the coun­termeasures available to the United States. As has already been noted, the Trident SSBNs are designed to limit the extent of the threat any area search capability might pose to that force. Indeed, even a few detections by a satellite-based system could b^e avoided in most ocean areas. Since satellite orbits are predictable, a submarine could simply l'^e “quiet” as the satellite passes overhead or adjust her speed so that the satellite never passes ov^er' head. Another possible countermeasure is procuring communication systems which free American SSBNs from the need to conduct operations in fh^e upper ocean layers where the satellite detectin'¹ threat is likely to be greatest. Alternative comm¹¹' nications systems, such as the ELF which could b^e built in a relatively short period of time, or perhap^s blue-green lasers sometime further in the future would help alleviate this vulnerability. Moreover- Soviet ocean surveillance satellites are likely to. the primary target of any American anti-satelh operations.                                                         .

Conclusion: While much of the appropriate *ⁿ formation on the Soviet ASW program and its im plications for the survivability of U. S. sea-ba^se strategic forces is classified, an analysis of °P^e sources tends to confirm the conclusion that Am^e ican SSBNs at sea enjoy a high level of invulner^ bility. There seems little prospect for a signifi^caj\ change in this state of affairs. This is not to discou the fact that the Russians are committing signifif^a resources to their ASW program. However. ^ll. important to note that, to the extent the distinct^ can be made, a large fraction of the Soviet A

investment is probably made with the goal of im­proving tactical ASW capabilities designed to pro­^vide better protection for new Soviet SSBNs oper­ating near the USSR. Indeed, this mission and the ^associated one of strategic strike seem to occupy the most prominent position in current Soviet naval declaratory policy. In any case, gradual improve­ments in deployed technologies are not likely to have any impact on the survivability of American SSBNs, especially in the face of U. S. technological ^and operational countermeasures.

Given these conclusions, there would seem to be little justification for the remarks cited in the intro­duction to this paper which seem to indicate a se­rous vulnerability problem by the 1990s. While it ^ls obvious Dr. Perry has access to information on Soviet ASW efforts not available to the public, his comments appear to run contrary to conclusions ^lhat have been made public by the U. S. intelligence immunity and most high civilian and military De­partment of Defense officials. Indeed, remarks like "^erry’s have provoked a certain amount of con­sternation as well as anger among senior U. S. naval officers. Moreover, only two months before his sur­prising comments, Dr. Perry himself reaffirmed the commonly accepted view when he stated before the S^enate Armed Services Committee that the intro­duction of the Trident I missile and the Trident sub­marine would give the United States “high confi­dence in the continuing survivability of our sea- 'aunched ballistic missiles.” An alternative expla­nation for Dr. Perry’s alarming statements is that ^hey were motivated by concerns other than some Postulated Soviet ASW threat to American SSBNs.

¹ is no coincidence that these comments have ap­P^eared in connection with efforts to preserve the mtercontinental ballistic missile (ICBM) leg of the S. strategic triad through procuring the MX sys- £m in a land basing mode. This is not the first time ,nat somewhat exaggerated assessments of sea­led vulnerability have appeared in connection "ath efforts to preserve land-based strategic sys- ^ems. An earlier case was during the debates on the ^ami-ballistic missile (ABM) system in 1969.

This leads to another important point; U. S. per­^CePtions of survivability are almost if not just as "dportant as actual estimates of Soviet ASW ca­pabilities. While the general consensus in the ap- P^r°Priate government circles is that the U. S. sea­led strategic force is highly survivable, underly- this consensus is a certain uneasiness. This is Probably caused, on the one hand, by the realization ^at the total invulnerability of that force when at _Q^ea might not be maintained forever and, on the Jner hand, by an understandable desire to maintain I ^at invulnerability. This desire has been intensified iP ^recent years by the perception among senior • S. defense officials that sea-based nuclear forces ^re increasing in importance within the overall stra­tegic equation. According to Admiral Kaufman, “as national reliance on the sea-based force expands with Trident and as technology advances threaten other elements of our Triad, the importance of main­taining high submarine survivability is obvious.” Indeed, a crucial underlying factor in the Navy’s drive to procure the ELF system has been the desire to enhance further an already high level of surviv­ability.

In these somewhat sensitive circumstances, pos­sibly combined with general uneasiness perceived over worldwide Soviet military and political ad­vances, any changes from past U. S. pronounce­ments on SSBN vulnerability could have an adverse impact on perceptions—possibly outweighing the actual significance of the threat. Therefore, state­ments like those of Dr. Perry or any other high gov­ernment official which signal even a minor, perhaps insignificant change from past assessments of SSBN survivability could serve to erode U. S. confidence in the continued effectiveness of a vital component of the U. S. strategic arsenal. Developments in either deployed Soviet ASW technology or in the operational uses of those systems might also stim­ulate undue threat perceptions. For example, it is possible to conceive of situations in which even in­creased trailing attempts might cause such exag­gerated perceptions. A successful trailing operation or the initial deployment of even an experimental space-based detection system, if learned about, could have an even more drastic impact.

In the context of sea-based systems, there is a spectrum of potential degradations in survivability, many of which fall far short of an actual capability to destroy even one ballistic missile submarine, let alone a significant number of deployed boats. In this sense, the task of destroying SSBNs is more com­plicated than that of destroying land-based missiles; therefore, any sea-based system vulnerability de­bate is likely to involve far more complex issues. Because of these factors, it will be all the more important in the future to avoid any oversimplifi­cations which might tend to propel the discussion beyond the proper proportions. We must keep the debate within bounds in order to avoid needless defense expenditures and perhaps irreparable dam­age to continued arms control efforts.

jH Mr. Wit holds a bachelor's degree in international relations from Bucknell University (1976) and a A master's degree from the School of International Affairs at Columbia University (1979) where he ^B specialized in international security studies. This article and several others on the subject of ASW and the future of sea-based strategic forces are the result of research sponsored by the New York office of the World Without War Council. Currently, Mr. Wit is a consultant at the Foreign Service Institute, Department of State, Arlington, Virginia. The views expressed here are his own and do not necessarily reflect those of the U. S. Government.