The First FrByo Sven Erik gJørgensenm - The Danish Societye ofn Diving History 2 Naval operations with the SLC (SLC: Siluro a Lenta Corsa, ‘slowmoving torpedo”) (continued and concluded from issue #7) In the years prior to World War water. As soon as the submarine was in II, the Italian fleet had devel- position, and the frogmen were out, the oped a new underwater weap- containers were opened and the SLC drawn out. The frogmen then tested all on, the SLC, a slow torpedo the functions of the SLC before setting which was manned by two out for the target. The first part of the trip divers. Submerged, and thereby took place on the surface, when only the heads of the frogmen were above the unseen, the frogmen on the surface. The frogmen had full face masks SLC could get close in to the on but breathed through a valve in the enemy ships and mine them. mouthpiece out to the air in order not to The frogmen trained in attacking deplete the oxygen stores. The harbours were gener- their own ships, and after many ally barred by submarine excercises developed a pro- nets which the frog- cedure for approach and men had to pass placing mines under the ships. either under or over. They could also cut their The submarine, which transported the way through SLC in pressurised containers on the using wire-cut- deck, sailed as close as possible to the ters. Free from target. One could then choose either the nets and into to release the frogmen while the sub- the harbour, the marine was lying on the seabed or, if it frogmen picked were possible without being discovered, out the chosen to let the submarine float to the surface target by its sil- with only its tower appearing above the houette because 85 X-RAY MAG : 8:8 :200 20055 EDITORIAL FEATURES TRAVEL NEWS EQUIPMENT BOOKS SCIENCE & ECOLOGY EDUCATION PROFILES PORTFOLIO CLASSIFIED The SLC sailing at the surface. To conserve breathing gas this was mode of the initial approach to the target the attacks took place at night. They had to get so close to the target that they could often hear and see the watch crew on the deck. During the last part of the trip on the surface the sternmost frogman lowered his head beneath the surface and breathed using his oxygen apparatus, so that there was as little as possible to be Painting by Rudolf Claudus, depicting the Italian frogmen mounting a mine seen by any watchmen on the ships. on the stabilising keel of an enemy ship The leading frogman then also went over to breathing using his oxygen apparatus and was ready to release the air from the tank of the SLC. In that sailed towards the target the frogmen they had come until the stern-most frog- informed him that the wire was now fixed activated. This would cause the mine to way could they quickly disappear from kept an eye on the remaining light filter- man felt the bilge keel. The bilge keel in place, and the SLC was now sailed explode 2½ hours later. He then released the surface if it happened, for example, ing down from the surface. is a thick piece of sheet-iron which runs over to the other side of the hull where the SLC from the mine and crept back that a searchlight could get close and When the light disappeared they knew along both sides of the hull in order to the procedure was repeated. There was to his seat. Three claps on the shoulder illuminate them. that they were beneath the ship. The SLC stabilise the ship against rolling. With a now a wire stretched out beneath the of the driver told him that the task was was stopped and a little air was released clap on the shoulder of the driver the ship. Holding the wire the frogmen now completed, and that it was now time to Acquiring the target into the tank between the frogmen so stern-most frogman told the driver that pulled themselves to under the middle get away. It was impossible to find a way When the target had been identified, that the SLC now had a slight positive he had found the bilge keel. He quickly of the ship. The stern-most frogman now back to the submarine and the frogmen, and at a distance of ca 30 meters from buoyancy causing it to rise up to the bot- took a clamp and a steel wire from left his seat and crept past the driver if possible, had to try and reach a neutral it, the leading frogman took a compass tom of the ship. The frogmen raised a the toolbox behind him and fixed in order to fix the mine, which formed coast where they could sink the SLC. This bearing and then let the SLC disappear hand over their heads to take the force the wire to the bilge keel using the bows of the SLC, to the wire. At the procedure shown to be possible during beneath the surface. At about 8 to 10 of contact with the ship’s bottom. With the clamp. Two claps on the shoul- same time the driver of the SLC held it training but was found to be much more meters depth the SLC was trimmed to sail one hand one the bottom of the ship der of the driver fast between his legs. After the mine had difficult during operations against the horizontally. It was now cold, dark and they returned in the direction from which been fixed the timing mechanism was Allies. quiet around the frog- men. As they slowly Line draw- ing of the Scire with SLC con- tainers on aft and fore decks 86 X-RAY MAG : 8: 2005 EDITORIAL FEATURES TRAVEL NEWS EQUIPMENT BOOKS SCIENCE & ECOLOGY EDUCATION PROFILES PORTFOLIO CLASSIFIED Depth charges being feature launched from British frigate would take a chance rather than await received a radio message from the inevitable. After some time a large Rome: ”The English fleet has left Attacking the British amount of air was released from the sub- harbour – return to Tobruk”. The On the 10th June, 1940 Italy declared marine – the hatch had been opened disappointment was great, so war against England and France. It was – and the survivors appeared one by one close and so had the fleet left now that the SLC could show what it on the surface after being trapped for 24 harbour. They were very close could do. The first attack was planned hours on the bottom of the sea. to the naval-base and prob- for the night between the 25th and 26th ably a watch at the base had August, 1940. The target was the English ”Enemy ship 800 meters” observed the submarine and fleet in Alexandria. The submarine Iride The next attempt was made in raised the alarm. After just a few took the frogmen from La Spezia to September 1940. The Italians would minutes sailing the alarm sound- Bomba west of Tobruk, where Iride met attack two English fleet-bases simulta- ed on the submarine: ”Enemy the torpedoboat Calipso, which carried neously – Alexandria and Gibraltar. The ship 800 meters”. Gondar dived the surface for only a few minutes before four SLC. This method of transporting the submarine Gondar sailed for Alexandria immediately, and a hunt now began it again sank. In spite of this, all the crew SLC was chosen in order to avoid dam- and Scire during which Gondar was under con- excepting one managed to escape from age to them should the submarine be for Gibraltar. stant bombardment by depth-charges, the wreck. The attacking destroyer col- forced into deep water. After 9 days causing it to dive deeper and deeper. lected up the surviving frogmen and sub- On the morning of the 21st August, equipment. The frogmen and the diver at sea the The hunt continued all night, and in the marine crew, among them Toschi who when the SLC were being transferred to made contact with the survivors in the Gondar morning at 8 o’clock the Gondar could spent the rest of the war as a prisoner. Iride, and the submarine refuelled - ready submarine using knocking signal. The reached not take it any more and began to sink to carry out a test dive – three English tor- crew of the submarine signalled that Alexandria uncontrollably. All the air was blown into Attack on Gibraltar pedo planes appeared on the horizon. the external hatch of the sluice could on 29th the tanks in order to stop the dive. It suc- Scire reached Gibraltar at the same time They flew low over the sea and opened not be opened from inside. September. ceeded, and the Gondar stopped at 155 as Gondar reached Alexandria. Just 50 fire against Iride. A torpedo hit the sub- The hatch was stuck tightly in the At the time meters, but now an uncontrolled rise to miles from Gibraltar and 4 hours prior marine amidships and it immediately hatch frame by the explosion. However, intended for the surface began with an ever increas- to the planned attack Scire received a sank in 15 meters of water. the frogmen and the diver succeeded the opera- ing speed. The crew got ready to aban- radio message: ”The fleet has left har- in opening tions to start don the submarine as soon as it had bour – return to La Maddalena”. This time the hatch but Gondar reached the surface. Gondar floated on was not a success either.