Sub Hunters Take a Dive Pt 4
The “Best” Sub Hunter
The Navy will insist the most effective way to sink a submarine is with another submarine. This may be a true statement but not necessarily how the admirals would have you believe. Historically the most successful killer of submarines have been aircraft and surface ships, with about 250 U-boats sinkings apiece during the Second Battle of the Atlantic. Only 22 German submarines were lost due to other subs, and in the Pacific just 1 US boat was sunk by its Japanese equivalent. In all recorded history only a single sub has been sunk by another boat while both were submerged, the U-864 by HMS Venturer in February 1945.
During wargames with US nuclear boats Allied conventional craft such as the Swedish Gotland have bested US warships including submarines. Apparently, the Australians are especially adept at “killing” our advanced boats, specifically the Collins class HMAS Waller, according to Wikipedia:
HMAS Waller participated in RIMPAC 2000. During the exercise, Waller successfully “sank” two Los Angeles submarines, and moved into torpedo range of the aircraft carrier USS Abraham Lincoln without being detected.
During Exercise Tandem Thrust in 2001, HMAS Waller “sank” two USN amphibious assault ships in waters between 75 and 105 metres (250 and 340 ft) in depth, barely more than the length of the submarine itself.
We think the above is a history-making incident, as profound as the aircraft carrier exercises conducted by the US Fleet in the 1930s. Conventional boats are much quieter, smaller, and naturally more maneuverable than the very large craft now deployed by the USN. It could be that in a future war at sea, the nuclear submarine which is the scourge of the surface fleet, may be at risk as well from the miniature, apparently underpowered, and presumed less able versions of themselves.
The Aerial Threat
The problems of aircraft in modern anti-submarine warfare are obvious. Each operate in two different environments, one below the sea, the other well above it. Neither can effectively operate in the other’s natural habitat, so neither are a major threat to the other unless one invades the other’s territory.
When submarines sailed exclusively on the surface, before the advent of snorkels, nuclear power, and Air Independent Propulsion, the patrol bomber equipped with ASV (Air to Surface Vessel) radar had the advantage. Today as we have seen, the new diving boats are true submersibles, a major threat to all two venture in or near her dimension. With this theory in mind, the slow, hovering ASW helicopter may be at greatest risk. Here is DK Brown on the risks aircraft take, from his book, “The Future British Surface Fleet“:
In many ASW operations, a helicopter or patrol aircraft will be required to fly low and slow, which makes either vulnerable to even the simplest submarine-launched anti-aircraft missiles…It is surprising that more attention has not been given to such weapons as, even if they had a low success rate, their use would serious disrupt ASW as currently conducted.
In wartime, sub-launched SAMs would certainly be deployed. In the 1970s Britain experimented with a version of their Blowpipe missile titled SLAM (Submarine Launched Airflight Missile). The Soviets designed the SA-19 Iglas missile for use on its Kilo class conventional boat.
The Patrol Bomber still in frontline US service since the 1960s is the P-3 Orion. It is still a good platform despite its age with plans to replace it with the jet-powered P-8 Poseidon. Similar aging ASW workhorses are flown by allied nations include the British Nimrod and the French Atlantique 2. Listen to the following commentary on US patrol planes from Navlog.com:
Of the more than 10,000 hours flown by Navy P-3Cs in the Persian Gulf, none of this time involved ASW. Rather, the missions involved supporting ground troops in Iraq and performing maritime interception operations as part of the coalition’s stopping illegal smuggling of oil. While meeting the current needs of the service after essentially abandoning ASW after the collapse of the USSR, the world’s navies – the US Navy in the forefront — find themselves ill-equipped to counter the explosive growth in the Third World fleet of stealthy, fourth generation diesel-electric subs like the U-212/214-class and the Scorpene-class…The critical shortage of P-3Cs has resulted in an almost total cessation of training when a squadron returns home from deployment as most of its aircraft are quickly cycled back to the fleet for overseas operations. In 1991 the Navy had 25 active and 13 reserve VP squadrons, each with nine airplanes. Today it has 12 active operational and six reserve squadrons, with all reserve squadrons to have been decommissioned by 2007. There are simply no aircraft to spare for the reserves any longer. Today, the Navy is down to just three deployment sites with each squadron having just eight airplanes each, a total of 24 planes.
Here are some facts on Sonar and the US Navy’s SOSUS from DK Brown and his book “The Future British Surface Fleet“:
- Because (SOSUS) installations are fixed, they are vulnerable to countermeasures and they cannot be redeployed to meet threats in other parts of the world.
- Shortage of sonobouys could soon become a problem in a prolonged war, as would numbers of patrol aircraft.
- The range at which passive sonars of all sorts can detect these new, quiet submarines is much reduced, though many older, clanking boats will remain in service for years,’
- Since active sonar has to detect an echo, inherently weak, from the target, its range is limited and may be further reduced if the target submarine is given anechoic coating.
The Sum of Our Fears
Some may consider the bleak picture we have painted concerning the state of anti-submarine warfare leaves no room for hope. They may see the proud surface combatants conceding defeat, lowering their flags, and dropping anchor for the final time while the new U-boats range the Blue Ocean at their will. This need not be the case, if a concerted effort is made by Western navies to recall the basics of war at sea, rejecting the special circumstances of the Cold War when they had no peer rival for much of the period.
The number of patrol plane squadrons should be boosted dramatically, perhaps giving the Air Force a greater role by steering it from hot jet fighters. The use of unmanned aerials vehicles on all warships should proceed immediately. New hulls forms, smaller ships, a greater number of combatants at sea might restore at least a parity with the astonishingly capable stealthy attack submarine. Then when all is said and done, it will be up to the sailors themselves, as it always with in naval combat, to tilt the balance back in our favor, securing Freedom of the Seas for a new generation.