SOVIET SUBMARINE TRENDS

The Soviets appear to have a radically different philosophy for the design of their submarines–in
order to best function in a big seawar against the West. Specifically, their attack submarines are
reflecting a specialization of design to meet the demands of a specific primary mission rather than
being multi-purpose like the U.S. SSNs. At the same time, the Soviet emphasis on certain characteristics other than acoustic quietness is producing submarines which will necessarily fight
in a different manner than the high performance U.S. nuclear submarines, whether SSNs or SSBNs.
And most importantly, the Soviets consider their submarines to be the main and growing source of
offensive strike power at sea–unlike the U.S. with its attack carrier oriented Navy.

The manner in which the Soviet submarine force is developing–its trends into the ’90s–have
allowed for a crude form of interpretation despite the very scanty amount of unclassified information
presently available. Although the trends derived appear to be overly simplistic and based on too
little data, it is felt that additional bits of information are not likely to radically change any
of the trends shown. Comparison of these trends with similar u.s. submarine developments provides
a good appreciation of not only the Soviet trends but also their relentless consistency.

The direction of certain Soviet submarine R&D programs which are examined herein should also be
seriously regarded for the possible impact they may have on the balance of seapower in the next decade.

Fleet Compositions

The greater emphasis which the Soviets place on submarines is evident from the makeup of their Fleet–a fleet of about 250 major surface combatants of over 1000 tons, some 350 land based
aircraft and about 375 operational submarines (of which 180 are nuclear powered) plus another
estimated 100 submarines in a ready reserve. Maintaining this fleet orientation towards a
predominance of submarines is indicated by the steady building program shown below–which is
apparently being continued through the 80’s.

Submarine Force Levels
USSR Submarine Construction

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Of these yearly totals, about 8 are nuclear powered and the remainder conventional submarines. This construction program is apparently being balanced by retirements of obsolete conventional
submarines. Thus an almost level force of strategic and attack submarines is being maintained out into the ’90s as shown.

By comparison the submarines per year achieve by 1990 a submarines and about U.S. is building only 3-4 and with retirements should force goal of 100 attack 34 strategic submarines.
The nuclear submarine construction programs of the Soviets equate to about 4.6 attack submarines
and 3. 4 SSBNs per year for a total of 8 nuclear submarines annually. With six Soviet nuclear submarine construction yards providing some 24 construction positions, about half of the building
potential is being utilized. On the other hand, the U.S. presently has a maximum building potential of only about 5 nuclear. submarines per year–in two private shipyards, Newport News and Electric Boat. The graph of how nuclear submarine force levels are changing, as shown , needs some explanation. Because of the SALT I agreement Retirement of nuclear submarines due to old age is unlikely until late in the ’90s, since keeping their submarines in commission for 30 years or more is consistent with past Soviet policies for retaining very old-age military units. Significantly, the Soviets latest SSBNs-her Deltas and now the Typhoons–appear to be configured for under ice operations. This capability coupled with the great range of their SLBHs (over 4,000 miles) and the expressed intent to operate their SSBNs in “bastions” close to the homeland and “in the Arctic environment”, indicates a relatively new strategy for their employment. It also lends credibility to the concept of a survivable fleet-in-being in an extended war which can decisively influence the political outcome of the war through the threat it poses to an enemy’s homeland.

By comparison, U.S. submarine programs call for a ceiling of 100 SSNs and a force of 31 SSBNs
since the eventual force of all Trident submarines would provide 644 launch tubes–within the SALT I
limit of 656 tubes for u.s. strategic submarines.

Submarine Design Trends

• Hull Design of · Nuclears-As shown, the Soviets have steadily reduced the length to beam ratios of their nuclear submarine hulls, whereas the U.S., to date, has had successively greater ratios–after starting with the Skipjack class which was developed from the lessons learned from the Albacore.
• Size of Nuclear Submarines–The Soviets nuclear strategic submarines have progressed from the
  5600-ton, 3-6 missile tube Hotels in 1958 through the 9,300-ton Yankees in 1967, the 16 missile tube
  11,750-ton Deltas of the mid’70s and finally  today’s Typhoon of 25,000 tons with 20 missile
  tubes. On the other hand, the Soviets nuclear attack submarines respond to a philosophy of
  designing various types of sub.larines–each for a specific primary mission. It is a single purpose
  approach as opposed to the U.S. design philosophy which has reproduced, since Nautilus, a similar
  kind of multi-purpose but basically ASW submarine. Thus for the Soviets, there are a variety of
  trends created by specialization of their nuclear attack submarines–which they distinguish as
  torpedo-submarines (SSNs) and missile-submarines (SSGNs). As shown, Soviet torpedo attack
  submarines or (SSNs) respond, displacement wise, to two different basic missions. The increasingly
  smaller SSNs, best characterized by the titanium-hulled, 43 + knot Alfas are probably designed for the anti U.S. SSBN mission, whereas the increasingly bigger SSNs characterized by the Victor Ills and now probably including the new Sierra class appear to be well suited for the protection of the Soviet SSBN force.

Significantly, the Alfa needs only an anti submarine weapon to carry out its mission of destroying U.S. SSBNs whereas the Victor III would need anti sub, anti surface ship and even anti air weapon systems to protect Soviet SSBNs, plus an under ice capability–resulting in a larger submarine.

By comparison, u.s. SSNs show a single growth trend in displacement tonnage while increasing their various weapon capabilities.

The other type of Soviet nuclear attack submarines, the SSGNs, also appear to respond to two different kinds of basic missions. The early Echos with their 250-mile 2200-pound warhead
Shaddock missiles were undoubtedly designed for the anti attack carrier mission. And now the
Oscar with its 24 tubes for the SS-N -19 is seemingly an updated SSGN for the same mission. It was thought that the Charlies with their 30-60 mile antiship missiles were a reasonable step backward because of long range targeting difficulties for the anti carrier mission. But the subsequent Papa and what looks like its follow-on t the Mike, plus the Yankee conversions which might be oriented for either mission, would indicate that this type of SSGN is better designed for the anti convoy mission–the medium range missiles to take out the escorting screens and their big load of torpedoes to be used against the merchant ships.

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Various basic missions evidently create substantial differences in the characteristics of nuclear attack submarines. Thus, since mining is considered a “primary mission” for Soviet submarines, according to Capt. Thomas Brooks–writing in the January 1984 Proceedings, there should be this type of Soviet submarine evolving through several generations. But perhaps it is a conventional one which to date may have been disregarded because of 1 ts non-nuclear character. It would also seem that basically
logistics submarines should also be evolving, consistent with the Soviet’s development of single
purpose submarines. The submarine for reconnaissance of amphibious landing areas and
destruction of inshore underwater obstacles is evidently (from the recent submarine intrusions
into Swedish coastal waters) the mini -submarine operating from another submarine. Capt. Brooks
also gives a good rationale for the Soviet’s continuing construction program of new types of
diesel-electric submarines–which are reportedly showing increasingly greater submerged endurance
on the battery with as high as 10 days suspected. “Arrayed in barriers”, Brooks writes, “where she can take advantage of her quiet battery mode of operation, the diesel need not compete with the speed and endurance advantages of the SSN. A U.S. nuclear-powered submarine venturing into waters adjacent to the Soviet Union had better take into account the diesel barrier threat.”

The increase in size of Soviet SSBNs shown here reflects not only the increasing number of missile
tubes installed, but also the progressively larger weapons carried in the tubes, to gain increased
range and carry a greater number of MIRVed warheads.

• Speed of Nuclear Submarines – High speed in a Soviet torpedo attack submarine is apparently at a
  premium, both to quickly close a distant datum, determined by a third party observation, as well
  as to attack, using active sonar derived fire control information, and to evade enemy counterattacks. It seems imperative that very high closing speeds be used in order to reduce the area of uncertainty of target location, if active sonar is to be then employed as a localizing means. In addition, very high speed lends itself well to Admiral Gorshkov’s philosophy of having “quickly developing operations” in order to surprise an enemy–where “surprise” can mean not only catching an enemy unaware but also preventing an enemy from organizing his adequate and timely defense. As shown, the Alfa is credited with a 43 knot speed and according to Capt. John E. Moore, USN (Ret.) the Editor of Jane’s Fighting Ships, “The probability of the successor to Alfa, a comparatively small, deep diving and very fast
  submarine being in commission by late 1984, is high.” This seems to be the reported “new small
  nuclear submarine” of the Soviets. Capt. Moore also reports a Morskoi Sbornik forecast of a
  23,000 ton submarine of very high speed that may use unconventional power sources… The Soviets
  indicate a belief that a hybrid type of submarine, one which uses a nuclear power plant to steadily
  charge a fuel cell or battery or heat sink–which acts like a capacitor–can provide a great surge
  of power for short bursts of speed. Thus, speeds of over 60 knots do not appear unreasonable in the
  possible time frame shown. By comparison, U.S. SSNs have increased in speed only slightly over
  more than two decades. But for the U.S., speed is subordinated to quietness.

The use of very high speed along with difficulties in producing sufficient numbers of skilled personnel to man their submarines seem to be driving the Soviets towards a high degree of automation in their nuclear submarines. One Soviet designer sees as reasonable “a completely automated missile  ubmarine with a crew of 25-30 and a crew of 10-12 for a torpedo submarine.”Not only are the Soviets pursuing new power sources for propulsion to produce higher speeds, but there is also a continued effort to achieve significant hull drag reduction through boundary layer control techniques. The Soviets indicate that the secret of drag reduction lies in imitating the bionic principles used by underwater speedsters-dolphins, sailfish, squid, etc. To this end, a series of Soviet patents starting in about 1972 show the practical application of these bionic principles to hull coatings. The 1981 patent shown here seems likely to be in use today. It consists of: a compliant coating with anechoic qualities; soft porous material embedded in it to respond to boundary layer pressures; an electric blanket for heating control of the boundary layer; and a means to feed a polymer to the surface of the coating. Such a coating may produce up to 60 percent reduction in frictional drag on the outer hull. And it should provide a damping effect on act~ve acoustic sound waves hitting the hull, while producing a decoupling effect on noise transmitted through the outer hull of the submarine.

Following through on applying the bionic principles which allow squids to go at a speed of up to 75 knots, the addition of a cybernetic boundary layer pressure – sensing system with such  a compliant coating, as shown, plus the use of a  hydro-pulse propulsion system to allow the  cybernetic system to better react to pressure changes and control polymer ejection, are possible next steps for achieving speeds in the 60-knot regime.

However, improved methods of drag reduction are insufficient to provide such speeds.

• Propulsion Not only is hydro pulse propulsion likely to be utilized, but other forms of propulsion with higher efficiencies should be evidenced as the Soviets “depart from the traditional scheme of large-bladed, extermal propellers in favor of new methods.” Super-cavitating or ventilated propellers, ram jet propulsion and even magnetohydrodynamic (MHO) driven flow of water are techniques being
  suggested, while the pump jet has apparently been already utilized.
• Power plants – In addition to the hybrid idea noted earlier, which could be less costly than
  present “atomic powered submarines” and use a simplified nuclear power plant, other power plants
  with an increased horsepower-to-weight ratio appear to be under development. Reactors using
  gas or liquid metal are listed, as well as an MHD system which uses a heated plasma to provide,
  magnetically, a direct conversion to electricity.

Depth

Increased depth in Soviet submarines is evidently of great importance. One Soviet Submarine designer notes that “increased depth capability allows for a full utilization of high submerged speed.” Another says, “a deep-diving submarine becomes invisible to the sonar gear carried by the ASW surface forces.” Getting down into the deep sound channel–3000 feet or more “to significantly increase the operating range of sonar gear,” is also of great importance.

The graph shown is an indication of Soviet interest in hull materials for increasing submarine depth. It also shows what is considered to be logical development of these capabilities–the application of titanium being quite cons is tant, with the introduction of the 3000-foot depth Alfa. The u.s. by comparison is still in the HYS0-100 regime.

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Survivability/Unsinkability

The Soviets regard the submarine characteristic of survivability as one which they term to be its
“unsinkable” quality. This approach, in effect, focusses on making their submarines capable of withstanding the damage from an enemy weapon hit, or nearby nuclear explosion. The U.S., on the
other hand, sees the problem of survivability as one of submarine vulnerability to enemy attack and
presupposes that the best way to make a submarine survivable is to insure that it is never hit–or
be close enough to a nuclear explosion to sustain fatal damage.

Soviet submarines are all double-hulled, with an increased spacing between hulls in newer classes
to improve their unsinkable quality. The reported 4-meter separation for the new Oscar and up to 5
meters for the Typhoon indicate the extremes to which the Soviets are being driven to minimize
damage from torpedoes with high explosive warheads. The effort towards deeper diving submarines is also indicative of Soviet emphasis on tougher hulls which can, when operated shallow, better withstand the effects of nearby underwater nuclear explosions. The use of two reactors and
multi propellers or propulsion systems are Soviet means to insure against the kind of crippling
damange which inexorably leads to being sunk by subsequent enemy attacks. Internal compartmentation obeying the “two-compartment rule” which calls for the capability to withstand
the flooding of two non-adjacent compartments and still get the boat back to the surface is
evidently being practiced. Greater inherent reserve buoyancy in Soviet boats (the Soviets
indicate about 20 percent as compared to U.S. boats with about 12.5 percent) plus multi hard
tanks, forward and aft as well as midships, for buoyancy control, are implied in Soviet descriptions of how, not only is unsinkability achieved with the “flooding of a compartment” but, the submarine is likely to also maintain a capability to continue fighting.

Like the u.s., moreover, the Soviets see unsinkability as reducing the chances of getting hit. The reduction of submarine signatures, non-acoustic as well as acoustic is stressed–to minimize detection by the enemy, with subsequent weapon attack. The m·agnetic signature of Soviet submarines is minimized through use of degaussing coils between the outer and inner hulls, the use of the non-magnetic titanium alloy in the Alfa and the expected use of fiberglass in hull construction. Hudrodynamic and infrared signatures are being markedly reduced with the use of better hull and conning tower shapes, compliant hull coatings, uses of polymers, etc. Wake disturbances as well as acoustic signatures aren being reduced with improved methods and propulsion. In fact, acoustic signatures created by any means are apparently being reduced as the newer submarines are reported to be considerably quieter than earlier classes of submarines. The addition of an anti-air weapon capability to Soviet submarines, the emphasis on countermeasures against enemy sensors and weapons and the heavy stress on electronic warfare efforts to reduce an enemy’s ASW attack potential, all serve to prevent weapon delivery on target.

Summary

The Soviet submarine trends and techologies described can only lead one to recognize that the
Soviets are building tough boats of increasingly higher performance for their own style of waging
war. The dominant role played by submarines in the Soviet Navy and the evident massive R&D effort
in progress as well as the past successes in meeting scheduled milestones, force one to contemplate how the u.s. must change many of its ideas about ASW to meet such a growing naval threat.

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