We should be nurturing an ongoing capability to operate attack SSNs in shallow water. During World War II the Japanese spent a lot of transit time hugging coastlines, ometimes behind minefields. Today the Soviets can be expected to do the same thing along the Northern Sea Route, which is entirely made up of coastal shallows. The Northern Barents Sea and the Sea of Okhotsk (both ice covered part of the year) are identified as SSBN operating areas in the 1987 edition of S9viet Military Power (GPO). Both seas have shallows that could be used to advantage by Soviet SSBNs.
The Maritime Strategy moreover specifies that during Phase II of a crisis (seizing the initiative): “We will wage an aggressive campaign against all Soviet submarines, including ballistic missile submarines.”
World War II Experience
One of the most dramatic submarine attacks in history was carried out by HMS TRENCHANT on 8 June 1945 . The Japanese cruiser ASHIGARA was intercepted and sunk at the northern end of Bangka Strait between Bangka and Sumatra during an attempted transit from Jakarta to Singapore. Hazlet , the skipper, positioned TRENCHANT in shallow water inside an Allied minefield in northern Bangka Strait. ASHIGARA came by on course 340° T, 17 knots, hugsing the Sumatra coast. TRENCHANT on course 280 T fired a spread of eight steam torpedoes, track angle 120°, firing range 4700 yards, and five torpedoes were seen to hit. Patrol report comments reflect AHSHIGARA’s dilemma:
“The target had made a navigational alteration of about twenty degrees to starboard, with the coast of Sumatra to port. At this point the stern wave of the enemy increased and I am of the opinion that he increased to full speed to avoid the torpedoes. He could not alter away as he would have run ashore and an alteration towards was the wrong avoiding action.”
It is obvious that the Japanese never expected a submarine to threaten from the confines of shallow water within a strait.
Can we expect to carry out such an attack with our SSNs?
During a 1944 patrol in the Kara Sea, U-957 took part in an attack that underscored the problems of fighting in ice-covered waters. On 18 September 1944, a convoy was intercepted on the Northern Sea Route near the western end of Proliv Vilkitskogo — the strait connecting the Kara and Laptev seas, located between the Siberian Mainland and Severnaya Zemlya. Schaar, the skipper of U-957, pressed home his attack amidst patches of drift ice. The attack periscope was peened over by an ice floe, hence tracking involved sonar bearings part of the time. Using the secondary aircraft periscope, an attack position was reached. One torpedo fired at a merchantman exploded prematurely, probably due to a collision with ice. As escorts started to harass the u-boat, the second periscope was bent over during evasive maneuvers . U-957 retreated westward, went deep and blind. Schaar periodically trimmed down aft and probed the surface for ice with the bow. Eventually, U-957 returned to base with buckled bow torpedo tube shutters added to her list of casualties.
The Soviets probably never expected to be attacked by a submarine in ice-floe waters. From the German point of view, the susceptibility of weapons to ice floes came to the forefront during this patrol.
Recent Trends in Submarine Displacement
It would seem that the Maritime Strategy and development of SSNs are out or step when it comes to opposing Soviet submarines in shallow waters or ice-covered shelves . Bigger and bigger submarines seemingly make shallow water cps less feasible. The latest point on a nearly linear (with time) plot or ever-increasing submerged displacement of SSNs is summarized in Table 1.
The Weapon Problem
Lack of maneuverability in close quarters, inherent in large submarines, is a serious problem. But of equal seriousness is the kind of weapon for use in a shallow water environment. History and today’s technology would show that a quiet, wakeless, “cool” torpedo is indicated. Others have recommended RPVs. In retrospect, during tlorld War II, we had a good idea — with the Mk 27 submarine-launched mine. This weapon had an 877 pound charge that could be delivered 4500 yards away at 10.5 knots . Upon reaching the preset range, it bottomed.
Attacking an SSBN lying doggo on the sea floor or resting against the ice canopy in shallow water is a tough challenge. A quiet, “smart” wire-guided weapon of some kind should be developed on a high priority basis.
The Delivery Vehicle
The STURGEON-class SSN is probably as close to an all-purpose submarine as we can get. It can operate in any environment in the World Ocean . The later LOS ANGELES-class should be able to do almost as well.
We must exercise foresight with regard to the real problems attendant to employment of attack submarines in other than deep waters. The shallow water problem will not go away.