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On the night of December 9, 1917,fast motor torpedo boats of the Italian Navy raided the Austrian port of Trieste, sinking the coastal defense battleship WIEN.  This assault highlighted a year which would witness the sinkings of various other Austrian warships and drive the embattled Austrian Navy to bottle up what was left of its fleet in the well-defended and fortified home port of Pola.  Here, it was felt, they could regroup and plan in safety, out of reach ofthe dreaded Italian raiders.  The Italians learned of this and undertook a plan of their own.

In the early morning hours of November 1, 1918 two swimmers, Major Raffele Rossetti and Surgeon Lieutenant Raffale Paolucci, guided what was essentially an old 14″ bronze torpedo-through the nets and barriers of the harbor entrance. In time, they reached the YUGOSLAVIA, which only a few days before had been the flagship of the Austrian Navy, VIRIBUS UNI17S, whereupon they disconnected a detachable warhead. 1he mother torpedo, now unladen save its own internal warhead, was pushed off in the direction of another large shape, also named a transatlantic liner WIEN. In the meantime, the two swimmers went to work attaching the first warhead to the side of the massive battleship. Off in the darkness, the torpedo motored under its own power for a short distance before slamming into WIEN, whereupon the remaining warhead detonated and tore a gaping hole in the side of the hapless liner.

It was then that sailors aboard UNITS, now alerted by the attack on WIEN, spotted the two divers and took them aboard as prisoners. Fifty feet below their feet, the last seconds ticked off the bomb’s timer and, according to Paolucci, “a dull noise-a deep roaring” rumbled through the steel bulkheads of the battle-ship, followed by a “high column of water”.1 Within minutes, the ship that had been the pride of the Austrian fleet, her hull opened to the Adriatic, capsized and sank.

This dramatic example can be said to be the birth of the mini-submersible at war. Prior to this, submarines were indeed diminutive in comparison to today’s monsters, but they represented the height of technology and not a distinct desire to develop something small and stealthy. Today, midget submarines, hereafter referred to as minisubs, are known to be operated by Columbia, Libya, North Korea, Pakistan, Yugoslavia, Sweden, and South Korea among others.2 Evidence has also been accumulating in the form of undersea tracks along the coasts of Brazil and Sweden that indicate that the Soviets are more than likely operating some form of tracked minisub.’

The United States, to date, operates only small submersibles, called SDVs, or swimmer delivery vehicles, for use strictly by naval Special Operations Forces (SOF). In an era when the world seems to be changing to meet the times, only the United States lags behind in resurrecting the potent power of the mini-submersible.

When a brushfire war, or regional conflict erupts, it bas always been a submarine that bas arrived on the scene first. With diverse operational areas and unlimited range, they are the ideal platform for first response. And what can a submarine do when it gets there? Just about anything it wants. From inteligence gathering to tactical cruise missile strikes, and from covert insertion of troops ashore to mine warfare, the submarine is a jack-of-all-trades. Yet, there are occasions” when the mini-submersible would be better suited to some of these tasks, at much less risk, and much less cost.

Today, when the word submarine is brought up, visions of Soviet TYPHOONS and American LOS ANGELES Class attack subs come immediately to mind. So it would seem in the minds of those responsible for the security of ports and harbors world-wide. Some ports, especially those directly related to military operations, are wired for sound; others make use of magnetic anomaly detection gear. Some are considered too shallow and cramped for a submarine to enter and remain underwater. Routine anti-submarine patrols are carried out around major coastal military bases, all of whom are looking for that hulking black shape in the darkness (successful or not, their eyes are open). 5 In any event, the defensive measures taken will be geared towards keeping a full-sized attack sub, with its dreaded torpedoes, out. Yet, it has been proven that small craft with SOF teams are scarcely slowed by such measures. (Note the results obtained by U.S. Navy SEAL Commander Richard Marcinko and his Red Cell team during the simulated terrorist attack on the Submarine Base at New London, CT.)6 Now is the time for the minisub, a weapon for which there is no established defense.

During World War II, the mighty German battleship TIRPI1Z, known to be moored somewhere in the fjords ofnorthern Norway, threatened all Allied relief convoys between Europe and Russia. Oddly, she accomplished this not by her actions, but rather “simply by sitting in Altenjijord at North Cape, posing a potential but continuous threat to any ship which attempted the Murmansk run “.1 So seriously was this threat taken, that during the summer of1942, all convoys to Russia were halted, despite their desperate need on the other end. Needless to say, her destruction was accorded the highest priority by the Allies, and especially the British. Thus, repeated bombing attacks were carried out against her, with little to no success. The British were confounded. When they finally did locate her, they had to quickly assemble a fleet, equipped with an aircraft carrier, race up to within striking distance, then hope that one of the small bombs would score a lucky hit. Torpedoes were useless, as 71RPI1Z was often sur-rounded by nwre than one torpedo net. Another way had to be found. From this dile17U7Ul, the X-craft was born. Originally designed in 1941, the 30 ton midget submarines housed a crew of jour, along with four two-ton explosive packages. They were 51 feet long and a little over jive feet in diameter. As testimony to the bravery of their crews, the reduced size of the craft enabled only a one-half inch pressure hull between the sailors and the ocean. It was six of these vessels, towed by six larger T and S Qass submarines of the British Royal Navy that comprised the assault force against 71RPI1Z. They departed on September 11, 1943 from their berth at Loch Carnbaw in Northern Scotland and arrived at their rendezvous point at Kaafljord in Norway on September 22. 7he journey was not without its hazards, and they lost four ofthe six craft enroute to various causes.

And so it was only two X-craft that breached the anti-submarine defenses of Kaajijord. Unnoticed, they pulled up beneath the massive black hull of battleship and released their delayed action mines. Within minutes, the charges detonated and fractured the spine of 11RPI1Z. 7he X-craft attack proved successful and caused considerable havoc: the rudder was damaged, all three propeller shafts were bent and some turbines were unseated from their nwuntings,· cracks in the bottom caused jloodings and even the rear 38 em gun was dislodged from its foundation. 1 As a result, the vital convoys to Russia were able to resume, and 11RPI1Z never put to sea again.

Intelligence Gathering

Going to extraordinary lengths to obtain infonnation has proved a necessary task over the years, and with the advances being made in secure communications procedures and protection of informa-tion, it follows that the ability to take advantage of such opportuni-ties is one we should continue to develop. Technological advanc-es, however, have also brought about improvements in the way in which such transmissions and signals can be intercepted. Now, a specially equipped submarine can poke up any one of a variety of periscopes or masts and retrieve information from the enemy. Also, cameras installed in the periscope can, within minutes, obtain detailed photographs of coastlines and shore installations, without risking the lives of SEALs or other valuable assets. The addition of such surveillance gear to a minisub would create the perfect tool for such a mission.

Insertion and Ex-filtration or Special Operations Forces

During Operation Desert Storm, U.S. Navy SEALs carried out missions as diverse as “strategic reconnaissance, early warning patrols along the Kuwaiti border, hydrographic reconnaissance, direct action missions, mine hunting, and combat search and rescue” .9 With the advent of the SDV, covert insertion tech-niques improved dramatically. However, the obvious problem remained. How to get commandos ashore, with their gear, through hostile waters, undetected, over long distances, and back again. That problem was addressed with the piggyback.

Both the USS SAM HOUSTON and USS JOHN MARSHALL [Ed. Note: Both ships are now out of commission and have been replaced by KAMEHAMEHA and JAMES K. POLK.] have been fitted with large dry shelters on their decks which are used to house SDVs. The problem with this is that it requires placing the mother boat dangerously close (within a few miles) to a hostile shore. This usually does not present a problem during the insertion phase when all is generally calm, especially because the sub can head out to sea for a time if it wishes. However, during extraction, the story may be much different. If, for example, the SEALs have caused a commotion during their visit-chances are that someone will soon be looking for them. While it is possible for SEALs to dive to a submerged boat and be recovered, the threat still exists; the boat remains vulnerable. Not to mention what would happen if they were bringing someone back with them who was unable, or unwilling, to make the descent.

The Minisub Answer

It is important to note, however, that while these methods have proven themselves capable over time, one certain improvement bas met with opposition. This is the use of dry minisubs. The leading contender seems to the be 3gst9 built in Italy. Costing a mere $14 million each, the 3gst9 can hold as many as nine SEALs and crew. Its range is advertised at 400 miles subsurface and it is capable of reaching depths of over 2,000 feet. 10 So what makes this small craft able to operate at these parameters? Instead of using cumbersome oxygen tanks that must be stored internally, the hull actually makes up the gas storage system, both for the oxygen, and the exhaust. As the oxygen is used up by the motor, it is replaced by the waste gasses produced. The result? No bubbles. For propulsion, it makes use of a fuel efficient, compact, closed-cycle diesel engine housed in a heavily insulated compartment that allows the craft to motor along in near-silence that makes the craft silent.

So what does the future hold for this craft? The United States Navy reviewed the 3gst9 in 1988 and gave it favorable marks. So promising was the concept, in fact, that Congress approved $15 million for further studies. Since the money for buying an ASDS (Advanced Swinuner Delivery System) was to come from the fenced Special Operations Forces budget, the Navy did not have a budgetary voice. The Italian craft was finally judged to be inappropriate, but the need nevertheless still exists.

Such a craft would eliminate diver fatigue brought on by extensive underwater time in free-flooding SDVs. The SEAL operatives could remain warm and dry until the last possible moment and deposited in the location and depth of their choice. Additionally, this would eliminate the risk of placing a multi-billion dollar SSN in shallow coastal waters. It would also open up the cold-water regions to unrestricted access. Although the idea is seldom considered, asking a SEAL to swim even one or two miles in sub-freezing Arctic water is an invitation to disaster. Human performance studies have shown just how appreciably the human body reacts to such adverse conditions. When all these points are considered, it becomes clear just how badly the Navy needs the minisub.

An Example

The minisub had certainly come a long way in the past 48 hours. First, ferried by C-141 from Italy to Saudi Arabia, then off-loaded onto a trailer and placed by crane into the waiting cargo bay of the secretly converted merchantman SS WAL1ER JOHNSON. 1hen came the unchallenged journey up the Persian Gulf to the staging point 20 miles off the coast of Iran. Next, the merclumtman slowed-to stop would be to invite unwanted attention. 1he hidden outer door was opened, and the cargo bay allowed to partially flood. 7he ASDS was on its way.

That was two hours ago. Right now, the sonarman aboard the minisub is busy monitoring the enemy frigate as it passed over-head. As expected, the ship continued on its way, unaware tluu it had just passed over the very threat it was looldng for. Running silently on its diesel motor and encapsulated by a hull constructed of non-fe”ous metals, no enemy had ever looked twice when the minisub was around. 1he veteran sldpper ofthe boat looked at his copilotlsonannan, then back at the four passengers. He would never feel entirely comfortable with the SEALs, even though he had operated with them maTIJ times before. My QTIJOne would choose to swim around in the dark and cold was beyond him. Turning back to his duties, he noted on his virtual image screen tluu the steel net draped across the entrance to the harbor was rapidly approaching. Now it would get interesting. “Ensign, we’ll reach the barrier in two minutes,· recommend you prepare for lockout. 7he officer in charge of the small SEAL team replied with a curt “affirmative”, at which two ofhis group stood up and headed into the small diving chamber. Within minutes two of his team had deployed and made a hole in the net large enough for the sub to sneak through. 1hey left behind a small beacon so they could more easily find their exit on their return. Once inside the harbor, the periscope was poked up at regular intervals and photographs were taken of the harbor, its ships, and its defenses. Another twenty minutes, and they had reached their objective. 1he entire SEAL team deployed this time, all of them leaving through the wet/dry airlock. As this would take some time, the sldpper bottomed his boat and waited for their return.

The next day, spirits were high at the State Department. 1he Iranian ambassador had delivered the message that, after further consideration, American ships would once again be allowed to travel freely in the Gulf. Privately, he politely inquired as to whether or not any light could be shed on the recent disabling of the six largest missile boats in his inventory. Apparently, their propellers and shafts have been destroyed during the night and  would be out of action for four to six months..


While the concept of fighting in or from the littorals has only recently become the focus of everyone’s attention, the SSN has been practicing long and hard for just this day. As a matter of fact “in the past 20 years the attack submarine force has amassed more than 14,000 submarine days conducting submerged, real-world contingency operations and training exercises in water less that 600 feet deep”. 11 This experience should be applied to the formation of a special unit training in the operation of smaJl dry submersibles . Such a craft would provide an almost undetectable, and certainly unexpected, asset that could operate with impunity off the shore of the most heavily defended coastlines in the world. All this, without having to place at risk a billion dollar nuclear submarine and its crew. Less delectability, less risk, less cost, equal results. In this time of budget consciousness, the minisub seems to be the right answer at the right time.

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