The British decided to try using X-craft midget submarines in an attempt to damage or even sing Tirpitz.

The 12th Submarine Flotilla carried out specialised training during the summer of 1943.

The X-craft needed to be towed by ordinary submarines. Although the craft had an operational range of 2,400 kilometer (1,500 miles) at 4 knots, just sufficient to make the passage to and return from Kåjord, the living conditions were so uncomfortable that the crew would be exhausted long before they reached the target. The idea was that the X.craft would be manned by a passage crew and when they were close to the target they were replaced by a operational crew.

The codename for the midget submarine attack on Tirpitz was Operation "Source", but even within this overall plan there were three separate sets of plans to be prepared. Operation "Funnel" was the attack on the target in Kåfjord; Operation "Empire" was for the Narvik area between 67° and 69° north; and Operation "Forced" for the Trondheim area between 63° and 65° north.

In order to give the X-craft sufficient darkness and at the same time sufficient moonlight to make their approach up the fjords the attack had to be made during the period 20-25 September 1943, and the former was therefore chosen as the latest date for slipping from the towing submarines. This entailed a departure from the Loch Cairnbawn base on the 11 September 1943.

The six towing submarines that would be used was: Thrasher, Truculent, Syrtis, Seanymph, Stubborn and Sceptre. Satyr and Sea-Dog were held in reserve at Scapa Flow at 24 hours' notice.

Photos: X-5 onboard the depot ship HMS Bonaventure before the attack on the Tirpitz.

On 6 September the X-craft were hoisted inboard of the depot ship HMS Bonaventure for final preparations and the fitting of side cargoes. There remained only the briefing of the crews.

The Admiralty was well advised of Tirpitz's presence in Kåfjord, in company with Scharnhorst and Lützow, the latter in the adjacent Langefjord. On 7 September the first Spitfire reconnaissance for several days was flown and reported Tirpitz and Scharnhorst absent from their berths. Unknown to the British, Tirpitz and Scharnhorst had sailed for the bombardment of Spitzbergen. However by 10 September reconnaissance showed that Tirpitz and Scharnhorst were back at their normal berths.

The date for the slipping of the X-craft was known as D-day (subsequently to be used for a far more notable occasion). The towing submarines after leaving Loch Cairnbawn were to make their way independently to a position 120 kilometer (75 miles) west of the Shetlands and then to proceed on parallel courses 32 kilometer (20 miles) apart until about 240 kilometer (150 miles) west of Altafjord, when they were to steer for their landfalls. Each submarine had an area off Sørøy Island where it was to slip its X-craft just outside the declared mined area after dusk on D-day and was then to patrol there until 27 September before attempting to recover the returning X-craft. The X-craft themselves were to cross the mined area on the surface and to make their way via Stjernsund to Altenfjord, bottoming during the daylight of 21 September. They were to enter Kåfjord at dawn on 22 September.

Photo: HMS Thrasher with X-5 on tow leawing Loch Cairnbawn on 11 September 1943 to begin operation Source. X-5 made a succesfull passage across the Norwegian Sea but disappeared during the operation. Her fate is unknown.

At 1600 on 11 September Truculent with X-6 and Syrtis with X-9 on tow left Loch Caimbawn, followed at intervals of 2 hours by Thrasher with X-5, Seanymph with X-8 and Stubborn with X-7. Sceptre with X-10 having the shortest route sailed at 1300 on 12 September. The passage for the first 4 days was uneventfully made in fine weather. The X-craft were towed dived, surfacing every 6 hours or so for 15 minutes to ventilate the craft.

On 14 September Spitfire photographs were received in England and Flag Officer, Submarines was able to signal details of the defences and to allocate targets to the X-craft. Target plan No. 4 was adopted: X-5, X-6 and X-7 were to attack Tirpitz, X-9 and X-10 Scharnhorst ( both ships berthed in Kåfjord), and X-8 were to attack Lützow berthed in Langefjord, a long arm on the west side of Altafjord some 16 kilometer from Kåfjord at its head.

The next 2 days of the passage, 15 and 16 September, were to be very eventful for 3 out of the 6 X-craft.

The tow between X-7 and Stubborn was parted but they managed to stay in contact and an auxiliary tow was passed.

The tow between X-8 and Seanymph parted as well. They were separated for over 36 hours before they found eachother again and continued the passage.

Also the tow between X-9 (Sub-Lieutenant Kearon) and Syrtis was parted. Syrtis sighted an oil slick while searching for X-9. No further trace of X-9 was ever seen.

X-8 ( Lieutenant McFarlane) and Seanymph were again having difficulties throughout the 17 September. Due to technical problems there was nothing else to do but to jettison the charge. Unfortunately the explosion from the charge severely damaged X-8. The crew could only scuttle the craft and then taken on board of Seanymph.

Throughout the 18 September the remaining submarines continued to tow the X-craft satisfactorily. Truculent and Thrasher had experienced little if any difficulties and had made their landfalls on the preceding day.

Sceptre who likewise had an uneventful passage made a landfall on 19 September. It is worth noting that these 3 submarines and their X-craft were using the new nylon tow ropes; it was the herrip tows which gave trouble and parted.

By dawn on D-day, 20 September 1943, all 4 of the towing submarines with their X-craft were in their respective slipping zones, the operational crews safely transferred. Seanymph had been ordered to a patrol position some 96 kilometer (60 miles) west of Altenfjord, but Syrtis, the loss of X-9 unknown to Flag Officer, Submarines, had received no new orders and so had taken station in her originally scheduled area to help with recovery after the attack.

Photo: Aerial view of Altenfjord and Kåfjord, showing Tirpitz (see arrow) and the approximate route taken by X-5, X-6 and X-7.

Between 1830 and 2000 on the evening of 20 September X-5, X-6, X-7 and X-10 all slipped from their towing submarines and began to make their way on the surface across the declared minefield towards Sørøy Sund.

X-5 (Lieutenant Henty-Creer) exchanged shouts of good luck with X-7 (Place). It was the last time the latter was to be seen. No one know what happened and the craft has never been found.

X-6 (Lieutenant Cameron) continued on the surface until 0125 when she dived at first light and continued up Sørøy Sund submerged to the entrance of Stjern Sund and by dusk she was nearing Tommelholm, one of the Brattholm group of islands off the entrance to Kåfjord where the X-craft were to rendezvous if possible. X-6 surfaced to recharge batteries but had to make an emergency dive at the approach of a patrol boat. By 2100 they surfaced again. Shortly before midnight Cameron tucked X-6's bows between a couple of rocks to await first light.

X-7 (Lieutenant Place) had a comparatively uneventful passage up to the rendezvous. At 1630 they sighted a large ship, probably Scharnhorst, steaming north in the lee of Aarøy Island. X-7 also spent the dark hours among the Brattholm group of islands, charging her batteries and undertaking final maintenance, but no contact was made with X-6.

X-10 (Lieutenant Hudspeth) suffered from technical problems. Lieutenant Hudspeth decided to seek a discreet shelter on the north side of Stjernøy, to try and repair them. They spent all day of the 21 September making repairs though with little success, but at 1750 set off for Kåfjord. At 0135 an approaching vessel forced them to dive. Hudspeth later surfaced to ventilate the craft and because he was unable in any way to navigate while dived he made for Tommelholm on the surface. At 0215 he bottomed for the day in 59 meter of water and the crew set to work to try and repair the defects, hoping to be able to attack their target, Scharnhorst, during the night of 22-23 September.

In order that the X-craft should not damage each other a careful schedule had been laid down. The first period for attacking was from 0100 to 0800 on 22 September with a firing period for any side cargo of 1 hour after this, i.e. from 0800 to 0900. Thereafter there was to be an alternating cycle of 3 hour attack periods and 1 hour firing periods.

In Kåfjord Scharnhorst's berth by Auskarneset was empty but Tirpitz was secured behind her antitorpedo nets. There was also anchored in the fjord the repair ship Neumark, a tanker and a Norwegian ship, three destroyers, Z30, Z31 and Erich Steinbrink, and the very old Norwegian coastal defence ship Tordenskold, re-named by the Germans Nymphe and fitted out as an ack-ack ship.

X-6 (Lieutenant Cameron) planned to attack Tirpitz at 0630 on 22 September and started the journey into the Kåfjord. Just after 0700 X-6 slipped unseen through the boat gap in the A/T net. At 0707 X-6 ran aground at the western shore and broke surface. She was seen aboard Tirpitz and reported but mistakenly considered to have been a porpoise and was disregarded! At about 0712 X-6 again broke surface about 27 meter (30 yards) abeam of Tirpitz and was identified correctly. The periscope was flooded and the gyro compass had stopped due to the violence of grounding and the subsequent large angles of dive and rise to which it had been subjected. Cameron groped his way blindly in what he believed was the right direction and was caught in what he thought were the starboard side A/T nets surrounding Tirpitz. He broke clear and surfaced close under Tirpitz's port bow to be met with a fusilade of small arms fire and hand grenades. X-6 was too close for any of the battleship's guns to be brought to bear. it was obvious that escape was impossible so Cameron and his crew destroyed their more secret papers while he backed the submarine alongside Tirpitz and released both sidecargoes beside "B" turret. Then they scuttled the craft and surrendered to a German picket-boat. Cameron and his crew were taken aboard the Tirpitz.

At almost the same moment that X-6 was releasing her charges by "B" turret of Tirpitz, X-7 was doing likewise just a little further astern.

Place with X-7 had left Brattholme Island at 0045, an hour earlier than X-6, and had passed unseen and without incident through the boom at the entrance to Kåfjord at 0350. Then X-7 ran into trouble. The craft became severely entangled in a rectangle of nets which protected a berth in the middle of the fjord. Here X-7 remained enmeshed for an hour before her violent exertions enabled her to break free, but only at the expense of a defective gyro and a broken trim pump. By 0600 X-7 was free and Lieutenant Place decided to go deep beneath the anti-torpedo nets surrounding the target.

Lieutenant Place expected the nets to reach some 18 meter (60 feet) or so down from the surface but in fact another net covered the space below to the bottom of the sea-bed and X-7 was again entangled. She worked herself free but broke surface unnoticed and had to dive again, only to become enmeshed yet again at 29 meter (95 feet). Some erratic manoeuvres enabled her to break free. The gyro was now completely useless and Place let the craft come slowly to the surface so that he could see where he was. By some "extraordinary lucky chance" (Place's own subsequent report) X-7 had broken clear of the A/T nets and was inside them with nothing between her and Tirpitz 27 meter (30 yards) ahead. Place ordered the craft to 12 meter (40 feet) and struck the battleship abreast of "B" turret where he released his first side-cargo under the keel. He then went to 18 meter (60 feet) and having turned went astern under Tirpitz for some 55 meter (180 feet) and released his other side-cargo as nearly under "X" turret as he could estimate. The first grenades thrown against X-6 were heard as X-7 hit Tirpitz, so X-7 must have laid her first side-cargo at about 0723 and the second a couple of minutes later.

After releasing both side-cargoes X-7 was taken down to 30 meter (100 feet) and course altered to try and get her out through the gap where she had entered. However the compass was still not functioning and with no proper idea of a course to steer she was again caught in the nets. For about three quarters of an hour Place worked the craft on motors and by blowing ballast to clear her, but each time he won free it was to become enmeshed again. At 0740 X-7 broke surface and came under small arms fire, but cleared the net and dived to the bottom in 37 meter (120 feet). Getting under way but still blind X-7 again ran into a net somewhere off Tirpitz's starboard bow until at 0812 a violent explosion shook the craft free. Place again bottomed to inspect the damage but although the pressure hull was still intact the machinery was so damaged that it was clearly impossible to try and make the return passage. Place therefore brought X-7 to the surface close to a battle-practice target and climbed out on to the casing under a hail of fire, waving his sweater in surrender. He had just time to step on the target before X-7, her ballast tanks leaking, sank beneath him at 0835.

Place was taken prisoner and nearly 3 hours later Sub-Lieutenant Aitken made a successful escape from the craft but his two companions, Sub-Lieutenant Whittam and ERA Whiteley failed to follow him and died, having exhausted their oxygen supply before they could get out of the hatch. All 3 had been forced to breathe their escape oxygen for much of the time while flooding up as the water reacted with the battery acid to produce chlorine.

On board Tirpitz the day had begun much as usual. At 0500 the hydrophone listening watch had been secured and maintenance on the sets had been started when at 0707 an object was briefly sighted but mistaken for a porpoise and disregarded: it was X-6 running aground inside the A/T net. At 0712 X-6 was correctly identified when she again broke surface some 68 meter (75 yards) off the port beam (a note in Tirpitz's log states that times between 0710 and 0730 are inaccurate) and the power boat was manned at the gangway. At the same time the alarm was raised throughout the battleship by the alarm bell.

A certain amount of confusion seems to have arisen here by the misuse of the alarm bell. Instead of the correct number of rings for "submarine danger" the bell was rung for "'close water-tight doors", so that the actual threat to Tirpitz was unknown to most of her ship's company. The anti-aircraft armament was manned but X-6 was too close to the battleship and her attendant craft to allow them to open fire. The X-craft was seen to dive and then resurface some minutes later when a power boat went alongside, embarked the crew and endeavoured to take the craft in tow. At 0736 water-tight doors were all closed and the prisoners brought on board where their demeanour caused the Germans to believe that they had successfully completed their task. The order was given for Tirpitz to raise steam.

At 0740 a second midget submarine was sighted outside the A/T net boom. This was X-7 forcing her way out. A.A. guns opened fire, grenades were thrown and the destroyers Z27 (Erich Steinbeck) and Z30 told to drop depth-charges. The boom gate to the net enclosure was shut.

On the sinking of X-6 close beside Tirpitz at about 0730 it had been Captain Meyer's intention to take the battleship to sea as quickly as possible away from any danger that might have been left by X-6. Already divers were preparing to check the hull for limpet mines and a wire was being drawn along the battleship's bottom. However the sighting of X-7 outside the nets caused Captain Meyer to change his plan as there was obviously a possibility of danger in the fjord and he had no means of knowing whether the attackers carried a locomotive torpedo or merely some form of static mine. Moreover it would probably take at least an hour before Tirpitz could be under way. Since X-6 had been sighted on Tirpitz's port side it was probable that any explosive charge would have been laid on that side and Tirpitz's bows were hauled over to starboard with her anchors and cable-holders. Moving the stern, which was secured to the shore by wires, was not readily feasible.

At 0812 there were 2 violent explosions, almost simultaneously, and Tirpitz leapt upwards several feet. A very considerable amount of damage occurred. All the lighting circuits and much of the power supply were put out of action and the ship settled down with a slight list to port with No. 2 generator room flooded, as well as other adjacent compartments. Some minutes later a second midget submarine (X-7) was seen to surface and was fired on as a member of the crew came out and stepped on to a practice target. After the submarine was seen to sink the destroyer Z27 dropped 5 depth-charges in the vicinity.

At 0843 yet another submarine was sighted about 592 meter (650 yards) away broad on Tirpitz's starboard bow. Both heavy and light AA guns opened fire and several hits were seen as the craft went under water, probably damaged. 2 minutes later a destroyer dropped a pattern of five depth-charges over the spot. This must have been X-5 and is all that is known of the craft since Place and Henty-Creer had exchanged shouts of good-luck off Sørøy at 2315 on 20 September, 33 hours earlier. it is probable that Henty-Creer was waiting until the next "safe-to-attack" period after 0900 before attempting to force the nets.

Photo: Taken shortly after the attack showing Tirpitz and other German vessels in Kåfjord and Altenfjord. Note the oil slicks in the water.

The damage to Tirpitz was severe. There were splits in the bottom of the hull and buckling and distortion underneath and to outlet pipes. No. 2 generator room was flooded and all the other electrical generators shocked so that no power was available in the ship for two hours, which effectively prevented the starting of boilers and the ship putting to sea. Much of the machinery was shocked on its mountings and put out of action: the propeller shafts could not be turned and "A" and "X" turrets jumped off their roller paths and temporarily made unserviceable. P III twin AA mounting was jammed, range-finders and fire control equipment were severely damaged and W/T and radar equipment rendered useless. 2 aircraft were severely damaged and the port rudder was put out of action.

2 power supply ships were sent to aid the battleship, the Karl Junge and the Watt, the latter arriving in the afternoon from Langefjord. On 25 September the German Naval Staff decided, with the approval of the Führer and the C-in-C Navy, that repairs should be carried out in a northern port, but it was appreciated that the battleship might never again be completely and operationally efficient.

X-10 spent all the daylight hours of 22 September dived by Tommelholm, trying to make good her defects. By sunset X-10's defects were still not solved. Hudspeth (having heard the explosions) decided that any attempt to attack an alerted enemy in his defective craft would be virtual suicide. At 1800 on 22 September X-10 surfaced and began her homeward journey. X-10 reached the rendezvous position at about 2300 on 23 September. For a day and a half Hudspeth manoeuvred in the area, dived and surfaced, trying to contact a towing submarine, but without success and at 0430 on 25th September he set course for Sandøy Fjord, securing there towards dusk alongside the beach of Ytre Rappafjord. Here the crew of X-10 rested and cleaned up.

At dawn on 27 September X-10 again set off, this time for 0fjord 32 kilometer (20 miles) to the west, where a submarine was due to rendezvous that night. At 0150 28 September X-10 was in tow of Stubborn.

On 1 October Truculent and Syrtis were ordered to keep pace but a planned fleet operation caused their course to be modified. On 3 October at 1807 a signal from Flag Officer, Submarines, warned them of an imminent gale and instructed Lieutenant Duff in Stubborn to embark the passage crew and scuttle X-10. At 2045 on 3 October X-10 was sunk in 66° 13' N. 04° 02' E. The expected gale broke 2 days later, by which time the submarines were all safely in Lerwick.

Except for Seanymph who had been ordered to patrol to the westward, the other 5 towing submarines remained on patrol in their areas after slipping their X-craft. On 21 September the Seanymph was ordered to shift area and patrol off Andøy in the hope of intercepting any enemy ships moving from Altenfjord to Narvik after the X-craft attack. At about midday 22 September Sceptre received instructions to shift area and patrol off Kvaløy outside Tromsø but unfortunately she arrived just too late to see Lützow on her way south. The 4 remaining submarines were redisposed to cover the seaward side of Sørøy, clear of the minefields. From 23 to 27 September they remained on patrol, trying to rendezvous with any returning X-craft, unharrassed by any German anti-submarine activity which indicated that the Germans had not appreciated how the X-craft had made the passage to Altafjord. On the nights of 27 and 28 September the submarines searched off Sørøy, where on 27 September Stubborn found X-10 in 0fjord, and in the morning of 29 September they separately started back for Lerwick, where they arrived between 3 and 5 October. Sceptre and Seanymph remained on patrol until 4 October without incident and both were back in Lerwick by 7 October 1943.

So ended the first attack by British midget submarines and the first successful attempt to destroy or damage Tirpitz. Of the six X-craft which set out none returned home but their casualties were fortunately light. 3 men were lost on passage in X-9 and X-8 was scuttled without casualty. In X-5, X-6 and X-7, all detailed to attack Tirpitz, 6 men were lost and 6 men were taken prisoner and came safely home after the war. X-10 was scuttled without loss on the way home.

The attack had been a tremendous success. For the loss of only 9 men killed and six men captured the battleship had been severely damaged, perhaps irreparably, and put out of action for six months and the morale of her crew undermined.

Throughout the winter months of 1943-44 the Germans laboured in Kåfjord to repair Tirpitz, with special ship workers based on the repair ship Neumark.

During the night between 10-11 February 1944, 15 Soviet bombers, each carrying a 2000 lb bomb, set out with Tirpitz as their target. Only four of these located Kåfjord and none of them hit the ship, although one was credited with a near miss.