Iran recently concluded the Great Prophet 5 naval exercise which feature swarms of speedboats attacking a corvette sized vessels with 107 mm rockets and machine gun fire. The pictures released showed swarms of small boats battering a hapless and burning target. The message is that this could be a tanker — or a US destroyer — in the Straits of Hormuz. According to Defense Tech “Iranian small boats will operate near shores using geography to mask their presence, use hit and run attacks, will operate in groups and attack ships with limited mobility in congested sea lanes, straits or entering or leaving port.” The tactics are reminiscent of World War 2 PT or “E” boat attacks.
One of the USN’s answers to this problem is the Littoral Combat Ship concept. These ships are very fast multi-modal carriers which carry small boats, helicopters, surveillance packages and whatever else the mission calls for. The payload can be tailored for a specific mission. But presumably one its missions will be to operate in the Persian Gulf, enforcing a blockade and keeping the sea lanes open. Presumably an LCS will be able to surveil, stop and search a great deal of shipping in crowded waters yet be able to defend itself against swarms of speedboats like those showcased in Great Prophet 5, missiles from shore or submarine and mine threats.
That’s a hell of a mission. A naval postgraduate thesis abstract summarized what a Littoral Combat Ship was supposed to do. But it also hinted at the kinds of tradeoffs it would be forced to make. It would have to be ‘expendable’ but capable. It would have to be fast but have a long endurance. It would have to be stealthy yet pack a humongous engine for speed. Those called for so many contradictory design elements that some compromise would be necessary.
The purpose of the Littoral Combat Ship (LCS) is to provide the Navy with an affordable, small, multi-mission ship capable of independent, interdependent, and integrated operations inside the littorals. The LCS will be designed to replace high-value Naval assets when conducting high-end missions such as littoral Anti-Submarine Warfare (ASW), Mine Warfare (MIW), and Anti-Surface Warfare (ASuW) as well as low-end missions such as Humanitarian Assistance (HA), Non-combatant Evacuation Operations (NEO), and Maritime Intercept Operations (MIO). To accomplish these missions and successfully counter the enemy’s littoral denial strategy, the Navy has stated that the LCS must incorporate endurance, speed, payload capacity, sea-keeping, shallow-draft, and mission reconfigurability into a small ship design. Constraints in current ship design technology make this desired combination of design characteristics in small ships difficult to realize at any cost. This thesis analyzes the relationship between speed, endurance, and payload to determine the expected displacement of the LCS; determines the impact of speed, displacement, and significant wave height on LCS fuel consumption and endurance; and analyzes the implications of findings on LCS logistics. The Joint Venture high-speed, wave-piercing catamaran is utilized in this thesis as the LCS seaframe to demonstrate the logistical implications of the speed, endurance, and payload tradeoffs with respect to the modular design of the ship. The weight and space requirement of each onboard and modular system is determined and added to that of the Joint Venture seaframe. Factors considered for full displacement calculations include the base seaframe, installed weapons systems, command and control systems and sensors, personnel and supply load levels, fuel storage capacity, ordnance load levels, and modular systems (embarked manned and unmanned air and sea vehicles).
The LCS idea grew out of the larger need to distribute naval combat power. Some analysts felt that capability had become too concentrated in a limited number of hulls. When the scarce hull wasn’t there the capability was absent. The suggested solution was to create ‘expendable’ hulls which could distribute hitting power amid more platforms creating more “tactical stability”. Instead of having 3 dozen eggs in one basket, they would have lots more baskets among which eggs could be shared. They would resemble nothing so much as hi-tech versions of pirate ships. A mothership would be a center of a host of networked assets: helicopters, small boats, robotic underwater vehicles and UAVs. The watchword was “distributed offense, distributed defense.”
The result were the two ships of the Freedom and Independence class. They are magnificent vessels. Faster than a PT boat, able to cross oceans, radar evading and able to swap combat packages in and out. They can deploy robotic, missile firing speedboats. With an ASW package, they have by some estimates up to 10 times the capability of a Cold-War era Spruance destroyer. But that very fact has been criticized. By becoming a kind of naval one man band, some feared it became a jack of all trades and master of none. Some sources on the Internet have claimed that by packing so many missions into the LCS concept the Navy has set itself an impossible task. In particular it has been claimed that the ship is too fast to have much endurance and too noisy to hunt submarines. A relatively small ship able to travel at high sea states at 50 knots simply could not have a very large endurance. And why would a mother ship need to do 50 knots anyway? Wasn’t that what helicopters were for? As for hunting quiet diesel electric subs, one writer suggested it could be heard coming a mile away. It was suggested that the USN would be better off with a “diesel electric corvette”, a kind of surface submarine, able to turn the tables on what were essentially quiet moving minefields under the sea.
The threat to modern warships in the littoral is real. The South Korean Cheonan was recently cut in half by a torpedo fired by a diesel electric North Korean submarine, at least according to sources gathered by CNN. The Israeli corvette Hanit was struck and heavily damaged by a C-802 missile off Lebanon in 2006 ten miles off the coast of Beirut. The USS Cole was nearly sunk at a pier by an explosive laden rubber boat. In all cases, fairly capable naval units were ambushed by systems hidden in the littoral.
Both the Freedom and Independence class designs have been criticized as scandalously expensive counters to the cheap speedboats and coastal threats they are ranged against. However, their real value is probably as lead ships of the distributed combat power concept, which they may or may not validate. That can probably be reckoned from what they can see and track which other naval platforms could not otherwise detect. If one of the many LCS’ remote probes in the air, on the sea or under it are even now reading the serial numbers of Iranian missile batteries or tracking Iranian naval units without the mothership itself being within range, then the Navy will know whether or not they have value for money. They are not likely to broadcast the news one way or the other, however. And the public won’t know until actual events shows whether the concept works or not.