Type VIIC/42 U-Boats

The Type VII/42 capitalized on the deep-diving VIIC/41 while being an attempt to defeat sonar by coating the outer hull with rubber anechoic tiles. Tests had been ongoing since 1941, on U-67 until the project was abandoned. It was decided to enable these submarines to dive even deeper, using thicker steel for the pressure hull. However in all these yards not accustomed to armour, rolling equipment was limited to 28 mm (1.1 in). Still, with such pressure hull, weight went from 68.3 t (67.2 long tons) to 154.3 t (151.9 long tons) and that firced engineers to regained buoyancy by adding 4.7 m (15 ft 5 in) to 5 m (16 ft 5 in) in beam. The saddle tanks were also enlarged making for extra fuel and a range of 12,600 nautical miles (23,300 km; 14,500 mi) but a top speed limited to 17 knots (31 km/h; 20 mph), insufficient to catch rejuvenated convoys and a raise top speed, so it was also decided to keep the same diesels but to add a new section of 0.8 metres (2 ft 7 in) in order ton install superchargers, on paper for 18.6 knots (34.4 km/h; 21.4 mph). Twelve were ordered, and then the design was finalized on 10 November 1942. On 17 April 1943, 174 were ordered across twelve shipbuilding yards. However obtaining the new steel alloy slowed the process down due to the competition with the Army for Tank Production. Assembly was barely started when orders were cancelled on 24 July 1943 for the Type XXI. A few month before, in May 1943, a variant of the VIIC/42, armed with six bow torpedo tubes, called the VIIC/43 was also planned, and cancelled.

Development

To dwelve into the concept of the Type VIIV/42 we ned to go all the way back to 1941, when Karl Dönitz confered with his top atlantic flottilla commanders and elite U-Boat captains at his Lorient HQ in Villa Kerlilon, on current U-boat performances and what could be done to improve them. At the time, Professor Walter promoted his new chemical propulsion to massively improve underwater speed, funded and testing a first prototype in 1939, OKM skepticsm however was still there. Production, supply, and safe handling of hydrogen peroxide was a very serious limitation of this alternated design. The Type XVII became semi-operational but by late 1941 the Battle of the Atlantic seems very likely winnable in a short notice.

The OKM funded still extra development based on Walter’s ideas in low priority, until decision was reversed in 1943. In 1941 however, the OKM preferred the safer path of the Type VIIC. The first reunion was aimed at decerning the major ways of improvement, notably those that could be achieved with little effort. Captains wanted a higher surface speed but it was eliminated as too difficult to achieve without deep design modifications. It wa salso suggested a better outer hull streamlining but this was not implemented as it would disrupt current production. What was most promising was the fact how diving depth could be increased to escape depth charge attacks. Strenght of the pressure hull was not that critical as a modification. This seemed more doable in general, and this was the first objective reached: By saving 11.5 t (11.3 long tons) weight through a simpler diesel-electric engine installation shelving 10 tonnes (9.8 long tons). This resulted in a 21 mm (0.83 in) mm hull instead of 18.5 mm (0.73 in) for a diving limit at 20%. To maintain seaworthiness, the bow was redesigned and elongated by 13 cm (5.1 in).

U-94 comes back to St Nazaire, saluted by Karl Dönitz (Bundesarchiv)

There were dozens of minor changes, on ballasts, water tanks, batteries, erogonomics but the armament was boosted in the AA department, with a larger aft platform in two stages, the first having two twin 20 mm AA and the second aft a 3.7cm FLAK. There was an improved radio set, more advanced enigma machine, better sonar system (not ready however the production was launched) when it was decided to fix the design. The change was communicated to all Yards. This became the Type VII/41. It was delayed somewhat due to bottlenecks for improved sub-systems, but eventually implemented in all yards. The first Type VIIC/41 was on 14 October 1941 and the first delivered, U-292, was on 25 August 1943, at a time the situation in the Atlantic had dramatically changed. On 30 September 1943, Dönitz now promoted the Elektroboote. Flender Werke yard in Belgium continued working on the Type VIIC/41 and was ordered the VII/42. In total 88 Type VIIC/41 were commissioned (other sources 91 commissioned). From U-1271 onwards production was simplified and mines equipment were omitted.

Towards the VIIC/42

When it was clear by late 1942 that the planned Walter boats would be too complex to translate into operations and before the alternative desgn Tpe XXI Elektroboote was worked out, a stopgap measure was taken, leading to the much improved type VIIC/42. The Type VIIC/42 traduced the fear of U-Boat commanders when submerged of detection by sonar. Engineers came with a simple solution, coating the outer hull with rubber anechoic tiles (a solution adopted much later in the 1970s). It was hoped these acoustic sonar waves would be absorbed by the material, instead of bouncing back. The problem was to find the right absorbent material and the right glue to resist both pressure, cold and salt water.

In 1941, tests with rubber coating on U-67 ended disappointing, so the project was abandoned. Instead, ithe solition of “brute force” was chosen, just allowing these boats to dive even deeper, notably by basically using battleship armour, already combining excellent proterties of flexibility and harness, knowned and mature since WWI already. The fact of using thicker steel for the pressure hull using the rolled homogeneous technique at the builders yards, given what most were capable of, however limited this maximum thickness to 28 mm (1.1 in). That was still much better than 21 mm but the hull weight went from 68.3 t (67.2 long tons) to 154.3 t (151.9 long tons).

To compensate, engineers worked out an increase from 4.7 m (15 ft 5 in) to 5 m (16 ft 5 in) in beam to create more buoyancy. Saddle tanks were enlarged as well, enabling to carry more fuel oil and improved the range so much it now reached an amazing 12,600 nautical miles (23,300 km; 14,500 mi), as much as a large Type IX. Top speed remained moderate at 17 knots (31 km/h; 20 mph). It was however soon seen as insufficient for keeping pace with 1942 convoys, that were much faster. One reason was that once U-Boats sank all the “junk” cargo ships of before WWI, working on coal at barely 10 knots, new cargo ships were now available thanks to Kaiser Yards and many others, in the US, Britain and Canada, the Liberty and Victory ships, all fitted with 16-18 knots machinery. Even surfaced by night, U-Boats had a hard time gaining the center of the convoy to do their business. They had to work hard their diesels, “whiping them” until they broke down or wear out prematurely, further reducing service life.

There was no way around it, the new U-Boats needed a greater surface speed, but with a heavier hull and the same diesel engines there were bot many ways it could be achieved. Even though diesel manufacturers of the time like AEG and Daimler promised increased performances, engineers had the hull lengthened by 0.8 metres (2 ft 7 in), both to increas the lenght ratio for speed, and to provide extra space for more powerful superchargers, added to the diesels and reworked exhausts. With this additional power, it was hoped to reach 18.6 knots (34.4 km/h; 21.4 mph).

As the design was finalized on 10 November 1942, a preliminary order for twelve Type VIIC/42 was placed. Furthermore, six months later as plans were ready to be delivered, by 17 April 1943, a hundred and seventy four boats had been ordered from twelve shipbuilding yards. But due to production bottlenecks for this new nickel-rich steel alloy for the reinforced pressure hull, construction was not starting. Indeed, that type of allow was in high demand already for tank manufacturing that firecely competed for scarcier resources. The land war had all priority as Hitler wanted in mid-1943 to definitively win the war in the east.

The same year two “wunder panzer” had been introduced and great hopes placed in them notably at the monumental battle of Kursk, the Panther and Tiger, and both were well armoured using precisely high nickel-rich rolled homogeneous steel plating. despite Dönitz efforts in early 1943 and his promises to win the war at sea in late 1942, this never happened. So supplies to the Kriegsmarine, now managed by Speer, had to rule out and reduced cotas for shipyards. Speer even suggested to Dönitz dismantling surface ships badly damaged and in repair or even earlier U-Boats of little use, like the Type II and IIa, and Type VIIA and B still around. Assembly at the yards in any case had not yet even started (there was not enough steel) when all orders were cancelled on 24 July 1943. Dönitz found an agreement with Speer to obtain more steel, but the VIIC was ruled our in favor of the new Type XXI “Elektroboote” far more promising. Hitler also weighted on this when presented the project and Dönitz promised to reverse the battle of the Atlantic when enough would be available.

Builders

Howaldtswerke, Hamburg: U-699-U-700*, U-1147-U-1152, U-2001-U-2004 (Werk 849-850, 851-854)
Flender Werke AG, Lübeck: U-1339-U-1350 (Werk 359-370)
Kriegsmarinewerft, Wilhelmshaven: U-783-U-790, U-1901-U-1904 (Werk 168-175, Werk 176-179)
Germaniawerft AG, Kiel: U-1069-U-1080*, U-1093-U-1100*, U-2101-U-2104 (Werk 706-717, 732-739, 740-743)
AG Neptun, Rostock: U-937-U-942 (Werk 529-534)
H C Stülcken, Hamburg: U-913-U-918 (Werk 810-815)
F Schichau GmbH, Danzig: U-1115-U-1120, U-2301-U-2318 (Werk 237-242, 1616-1633).
Nordseewerke, Emden: U-1115-U-1120* (Werk 237-242)
Blohm & Voss, Hamburg: U-1423-U-1434, U-1440-U-1463 (Werk 273-284, 290-313)
Danziger Werft AG: U-1805 – U-1822 (Werk 167 – 184)
Flensburger Schiffsbau-Ges: U-1313-U-1318 (Werk 509-514)

*Howaldtswerke, Nordseewerke, and Germaniawerft AG were the quickest to lay down their boats. However when cancelled none was advanced enough to justify continuing.

Last Gasp: The Type VIIC/43

Early in 1943 as the Type VIIC/42 was not even started, it became obvious that convoy battles demanded a better armament, with more pre-loaded torpedo tubes rather than fewer torpedo tubes and more reload, no longer adpated to the higher pace of operations when an attack was ongoing. Given the risk of entering a convoy by night, after a lot of preparation and a more fearsome that ever answer by ASW escorts, it was very unlikely that U-boat would have the leizure to withdraw to reload and attack again. The other reason was that the potential Elektoboote program was still in its infancy. Some in the OKH estimated it would not be ready before December 1943 at best.

The VIIC/43 seemed a good stopgap and it was based on the Type VIIC/42 (still not cancelled at this point) but with six bow torpedo tube, two at the stern, much more in conformity to what other nations built (The US Gato class had the same, and the British T class even had ten tubes). But on 11 May 1943 it was decided to cancel the VIIC/43 and concentrate on the Type VIIC/42 and VIIC/42 instead. Both would be cancelled in July for the new Elektroboote. None of the VIIC/42 or 43 was ever completed. Both were phased out for the XXI Elektro boat bylate 1943, albeir plans for mass production agreed upon by Speer were quite ambitious and long in coming.

Design of the class

The Type VIIC/42 were derived from the VIIC/42, themselves based on the VIIC, with basically the same engine layout and output, same armament, 5 torpedo tubes (4 bow, one stern) but even stronger pressure hull for extra depth. Operational depth went from 200m (), crush depth estimated 400m () versus a Type VIIC/42 (120 m/300m) a standard VIIC, 100m operational, 200m max. If these boats had been built, it’s likely they would have saved many crews, leading to further depth charge setups and revision of practices in allied escorts. The Type VIIC/42 had the same lighter machinery to compensate for the extra steel in the pressure hull thannks to revised dieselsn more smartly engineered, lighter batteries, all for the same underwater power. In the case of the VIIC, no better diesels could be ready in time so it was dediced to “cheat” by adopting compressors.

Hull and general design

The Type VIIC/42 displaced 999 tonnes surfaced, “light”, and 1099 tonnes submerged, then 1,363 tonnes total submerged and fully laden. They were a tad longer at 68,70 meters overall (225 feet) and 50,90 meters (167 ft) for the pressure hull. The beam was however extended from 6,20 to 6,80 meters (22.3 feet) overall, and the pressure hull diameter went from 4,70 meters to 5 meters (16.4 feet) and and draught of 5 meters. To compare a standard VIIC had a 67.20 m long hull, 6.20 m wide, with 4.74 m draught. Total height from the keel to the portico above the conning tower, was 10 m (32 ft). Externally, not much changed either but in the shape of the conning tower, which tail was elongated to installed a heavier AA, on two stage (see below).

Powerplant

The VIIC/42 like the VIIC/41 had MAN M6V46 diesels for a total of 4,400 shp, thanks to superchargers, requiring adding another section of 0.8 metres (2 ft 7 in). The VIIC top speed of 17 knots (31 km/h; 20 mph) had been criticized but there were limitations to which diesels output could really be improved. It’s possible that due to bottlenecks some had received 3,200 bhp (2,400 kW) Germaniawerft F46. The superchargers were a game changer to reach 18 knots and more. They were not new. The Type IXs started to receive them in 1942 already, but not the VIIC, as they were too short. These types were small enough to fit in. The base principle was to blow compressed air into the diesels instead of having natural aspiration, forcing out compression and boosting speed. This however degraded the engine’s longevity and was selectable, only to be used to hunt down convoys at night. Underwater they would have likely either the Garbe, Lahmeyer & Co. RP 137/c and Siemens-Schuckert-Werke (SSW) GU 343/38-8, with a backup as the AEG GU 460/8-276 and BBC GG UB 720/8. However even with 750 shp total, top speed down to 7 knots underwater at best.

As for range, thanks to their larger saddle tanks, they jumped from 8,500 nautical miles at 10 knots surfaced to 12,600 nautical miles (23,300 km; 14,500 mi) well enough to criss-cross the Atlantic to the US east coast and Panama or to the Cape. Underwater, they were limited to 80 nautical miles (148 km) at 4 knots economical speed. As for max depht, tehy would operate way down to 270 meters (885 feet), but actual crush depth below 400m. In 1943 the allies senses the U-Boats were able to dive deeper and modified the operating depht of depth charges. However deepest it went, detonation range was buffered and less efficient, still. It’s why in the cold war, both sides started to introduced tactical nuclear depht charges as new Soviet submarines were able to dive below 500 m routinely.

Armament

Type G7e(TII) captured in Scapa Flow (dud) after being fired at HMS Royal Oak, preserved at Birkenhead.

Five 533 mm torpedo tubes (4 bow and 1 stern). 14 reserve torpedoes or 26 TMA or 39 TMB mines*. No changes compared to the VIIC
A 88 mm C35 L/45 deck gun as standard.
One 20 mm C30 machine gun in the CT aft platform.
From 1944: Enlarged CT for one 37 mm gun and a flakvierling (4x) 20 mm Flak.

If the Type VIIC had the same torpedo tube arrangement as their predecessors, U-72, U-78, U-80, U-554, U-555 due to shortages, had only two bow tubes and thus were used for training only. U-203, U-331, U-351, U-352, U-401, U-431, and U-651 had no stern tube either, for the same reason, albeit they were used in war patrols. Conversely, the C/42 it seems all had their regular torpedo tubes fitted, as Speer’s production reorganization bore fruits. This shortage made the VIIC/43 even more illusory.
*It’s likely the mines apparatus would have never been installed for simplification as was the case for the late VII/41.

Deck Gun: 8.8 cm/45 (3.46″) SK C/35

The type VIIA U-boats had the 8,8cm as deck gun. The Type IA and later Type IX had the larger 105 mm deck gun, and the small Type II had a 20 mm AA gun. This deck gun was produced by Krupp but had absolutely no relation to the famous German Army 8,8 anti-tank and anti-aircraft gun. They did not even share the same ammunition. The 8.8 cm/45 (3.46″) SK C/35 was also used on Type 40 minesweepers and sub-chasers. After 1942, many U-Boats had it removed to install more FLAK instead. Only in the Mediterranean and the Northern Sea, U-boats kept their guns for a few months longer. It seems the original 37 mm was only sported at completion but the first two boats and replaced, the 8,8 cm was installed at completion on all the others as the production at Krupp was ramped up.

This was a pure “marine guns”, with material resistant to corrosion, simpler mechanisms and lubrication was limited or made internal. The goal was to have a permanent deck gun that could stay very long periods underwater at great pressures that could damage mechanisms and smaller parts. It was tested in a pressure chamber to the equivalent of around 200m (650 ft) which was the max theoretical diving depth at the time. These constraints made for a completely different gun than the more complex land-based 8,8 cm FLAK gun. The 8,8 cm caliber had been used for many decades in the German Navy, all the way back to the 1890s and saw many iterations over the years. Unlike its land-based counterpart, it was a pure anti-ship model as it was limited by its mount to 30°.

The model used on the Type VIIC, unchanged for the C/42 was a very rugged gun, albeit not having the same punch as its land counterpart, and a AP round (AP 35) which was far weaker. At 700 mps (2,300 fps) versus 840 m/s (2,690 ft/s) it lacked the speed and range as well, but was very impressive an efficient as a naval gun, especially for such as “small” submarine. It’s just that from 1942, no U-Kaptain would be mad enough to try to sink a cargo while surfaced with this single gun, staying exposed for an hour or more. More

Specs 8.8 cm/45 (3.46″) SK C/35

Weight: 5,346 lbs. (2,425 kg), Barrel alone 1,711 lbs. (776 kg)
Length: 157 in. (3.985 m) bore 146.9 in (3.731 m).
Rate of fire: 15 rounds per minute
Shell: 33 lbs. (15 kg) 14 in (385.5 mm) HE, AP, Incendiary, Illumination (90-10.2 kgs).
Bursting charge: AP 35S 0.064 kg. HE L/4.5 0.698 kg, HE L/45 Inc. Brandkörper A
Propellant charge: 3.70 lbs. (1.68 kg) RP C/32, 3.90 lbs. (1.77 kg) RP C/38, 4.63 lbs. (2.1 kg) RP C/40N and PL/V41
Muzzle velocity: HE 2,300 fps (700 mps), Illum.: 1,970 fps (600 mps).
Range: 13,070 yards (11,950 m) at 30°. Depression -10° on Ubts LC/35 mount.
Ammunition stowage Type VII: 220 rounds.
Barrel life: 12,000 rounds.

AA Gun: 3.7 cm FLAK LM42 U

The 3.7 cm SK C/30U had a practical range of 8,500 metres (9,300 yd) at up to 30 rounds per minute. Their muzzle velocity was 1,000 m/s (3,300 ft/s), and the shell weighed 1.64 lb (0.74 kg). It was often located on the aft deck, after the conning tower.

AA Gun: 2 cm FLAK 30 U

The 2 cm FlaK 30 guns installed on the “wintergarten” (platform aft of the conning tower) had a maximum range of 4,900 metres (5,400 yd), reduced in practice to 3,700 m against fast-moving aerial targets. Their rate of fire was 280 rounds a minute at a muzzle velocity of 835 m/s (2,740 ft/s). The 2cm rounds weighed 0.71 pounds (0.32 kg).

Torpedoes

For the Torpedo tubes I-V, Piston was 70 kg, forward +25.25 with piston inserted, 1680m3 and aft: -26,15 without piston and 1740m3. There was an upper deck container forward and aft, with and without G7A. Torpedo in the tubes were the G7E/G7A models. There was also a reserve stowage forward, aft. Note: The “Torpedokrise” lasted until the end of 1941. The result were scores of duds or precocious detonations. It was less severe than the infamous USN Mark 14, but limited the effectiveness of the Type VIIA, B and C until solved.

G7A Torpedoes

Direct involvement of Spain in the development of German torpedoes started in the late 1920s when the Spanish businessman Horacio Echevarrieta decided to start a torpedo factory in Cádiz (Fábrica Nacional de Torpedos, F.N.T. / National Torpedo Factory) with a theoretical production capacity of 100 torpedoes per year and license-build German torpedoes. But the G7 was created in WWI. The lineage comprised the pre-WWII G7A (T1) using compressed air and thus leaving a visible trail of bubble.

The G7a (TI) torpedo calibre was the standard 533.4 mm (21 in), for a length of 7163 mm (23 ft 6 in), fitted with a Ka or Kb warhead, Pi1 or Pi2 pistol. The warhead carried 280 kg (617lbs) Schießwolle 36. The model remained standard issue from 1936 to the end of WW2. This model was of a straight-running unguided model only controlled by a gyroscope. It could be set at a variable speed, 5,000 m at 81 km/h or 7,500 m at 74 km/h (8,250 yd at 40 kt) but also “long course” 12,000 m at 55.6 km/h. The 44 knots model setting was only used by Schnellboote with a reinforced engine.
Later were introduced the G7a (T2) electric, T3, T4, T5 (Zaunköning), and T11, but the latter remained a prototype. It was probably still used on the C/42 for training only. In 1940-41, the G7a T2 was already standard.

G7E Torpedo (T2)

The T2 had a unique setting of 5000m at 30kts. Standard torpedo of the war, it suffered from early issues with the internal depth-keeping equipment and firing pistol, solved after the Norwegian Campaign, but only gradually implemented. The “torpedokrise” was thus only resolved in mid-1941 when all stocks had been changed or spent. Full effectiveness on the T2 was obtained when preheated electrically to 30 degrees Cent (86 F) before firing. If not, speed was down to 28 knots for 3000m.

The G7e(TII) already entered service in 1936 and was a “secret weapon” for the Germans as much as was the “long lance” (type 93) for the IJN. Its existence was virtually unknown to the British until fragments were recovered following the sinking of HMS Royal Oak in October 1939. The G7e was electric, no longer using a wet-heater (steam-driven) and was simpler and cheaper to manufacture (half the cost), as well as being virtually silent, leaving almost no visible trail of air bubbles.

The latter was by far its biggest advantage. It was virtually invisible in the dark North Atlantic and spotters needed to be posted high and have an excellent view to see them via the water disturbances they still create at this speed, so a very faint trail underwater, still. It was most often heard first but the hydrophones’ operator, getting a bearing.

The T2 had many issues, it was however less reliable and performed unpredictably compared to the G7a(TI). Just like the Mark 14, both the contact and magnetic detonators were unreliable. But the feedback loop was quicker and there was less inertia from the engineering department to solve these issues way quicker than in the US. The T3 became the Stradivarius of the G7 type in 1942. It’s likely it was only used for training or reconverted, and the U-Boote Typ VIIC/42 never used it when entering service.

G7E Torpedo (T3)

By mid-1942 the improved version had an increased battery capacity, asking for a 50% superior range as the T3a. Range was now, 7500m at 30 knots, but in a preheated state it was 4,500m at 28 knots. More detail to come for the next articles on the Type VII. Thy did not have the previous faulty exploders and had a brand-new system, with a perfected proximity feature. This enabled what the US and other navies looked for, a torpedo that can dive below the keel of a ship and explode, breaking it. They were still in large quantities in the inventory an,d became standard on the Type VIIC/42. However by 1943 far better and more intersting models started to make the venerable G7 far more interesting:

G7e Falke Torpedo (T4)

The Falke was the model allowing a sub to fire them while deeply submerged inside the convoy. Their main advantage was to start like a straight-running torpedo for the first 400 m (440 yd) to enable its acoustic sensors, then actively search for a target. Since this equipment was sentitive, the propeller needed to be as quiet as possible, by its shape, and also speed, at only 37 km/h (20 kn), while the Carrier sub was also to be dead silent. This model was mostly intended for merchant targets. Its use was limited, as it was merely a “proof of concept” for the acoustic homing torpedo.

G7e(TIII Fat II) Torpedo

FaT stands for Flächenabsuchender Torpedo. This model had a devise to changed the torpedo’s course over time so that it ran various patterns. Three versions: Fat I, II and III (Fat III was later redesignated Lut I).

---

Improvements in the design of the G7e called TII, were incorporated in production for this electric torpedo introduced in 1942. This TIII was a massive improvement over the TII with the following:
-The well known faulty exploders was upgraded to a brand new design.

-Range was the same as the TII, at 5,000 m (2.7 nmi).

But more was to come.

TIIIa

The TIIIa increased performed by fitting new batteries for a a range of 7,500 m (4.0 nmi) at 30 knots (56 km/h), still in straight line. Complement by the G7a(TI) wet-heater model only used at night for the rest of the war, the TIII was used for day-attacks thanks to its near invisible trail. It had better proximity feature so that an able U-boat captain could now in effect fire under the keel of a ship, breaking its back. The same “tactic” is still used today. And thanks to a single torpedo when in the past several were sometimes needed to sink buoyant cargos ships and even through tankers. This helpled massively increase overall effectiveness with an unchanged number of torpedoes.

TIII FAT II/LUT II

Soon, it was improved with the program steering FaT – G7e(TIII FaT II), and LuT – G7e(TIII LuT II) which were pattern running systems to be launched on well-defended convoys. The FaT (Flächen-Absuch-Torpedo or Federapparat-Torpedo) and LuT(LageUnabhängiger Torpedo) at first ran straight out and then started a circular or ladder-like pattern through the convoy lanes, being impredictable. Ships had no idea how to manoeuver. This not increased the probability of a hit but also completely distrupted the carefully laid ship lines, augmenting the risk of collisions, as deadly as a torpedo hit and making the work of escort much more difficult.

There was a single setting to regulate the length of the prerun, then four possible settings would be activated in sequences making the torpedo zigzag left or right over 1200 m or 2-3 nautical miles, or on a longer path of 1900 m or a full nautical mile o,ce fire. However this “wunderwaffe” was not without risk for oother U-Boats, and if one launched such weapon, other U-Käpitan needed to be warned in the vicinity. They were vividly encouraged to dive to avoid being struck by. These FAT torpedoes could be converted on the line, without too much complex items and became available in late-1942, just in time to be sported by the Type VIIC/42. They became a regular feature of the convoy battles of March 1943.

TIIId “Dackel”

Thus further modified pattern-running variant had a much greater endurance of 57 km (31 nmi), however at 9 knots (17 km/h) only. It weighted 2,216 kg (4,885 lb). Like the FaT and LuT, it started to run a ladder search pattern at the middle of a convoy, made of four lanes in general.

TIIIb

Additional variant, the TIIIb weighted 1,347 kg (2,970 lb) due to its new propulsion module based on the human torpedo types, Neger and Marder. Top speed was 18.5 knots (34.3 km/h), range 4,000 m (2.2 nmi) at full speed.

TIIIc

The TIIIc had the same weapon payload as above but for a reduced weight of 1,338 kg (2,950 lb). Top speed was also of 18.5 kn for 4,000 m (2.2 nmi). But there was an alternatove setting to 4 knots (7.4 km/h), greatly increasing range.

TIIIe “Kreuzotter”

A relative development which had the same payload by the midget submarines Molch and Seehund, over 1,343 kg (2,961 lb), top speed of 20 kn (37 km/h), range of over 7,500 m (4.0 nmi).

TMA Mines

In alternative to their torpedoes, the Type VIIC/42 U-Boats could also carry 22 TMA mines, two for one torpedo. The Type VIIs made in fact many minelaying missions, albeit crreating quite small minefields given the surface to wartime cover size so Captains had to decide to place them on very strategic points, helped by detail maps to be sure they will be across obligatory lanes for coastal traffic. Losses due to these were few however, both given the small minefields and low power. These TMA mines were shaped as cylinders, used as moored mines, attached by cable to float above the surface, while the anchor secured its position. The correct depth setting needed to be applied depending on the observed depths.
Two could be carried in each torpedo tube.
Length/Diameter: 11.1ft (3.38m)/21in (533mm)
Maximum Depth: 270m
Warhead: 215kg.

Equipments

Snorkel

That war-winning device (or so it was thought for a time) was designed to allow an U-Boat to keep proceeding underwater under diesel power, not electric, thanks to a “breething apparatus” enabling the diesels to take fresh air and exhaust combustion product through a single mast-like device the Snorkel. Actually a Dutch invention fetched when the Netherlands fell in 1940 for its own submarines, it was quickly perfected and work started to test a workable version on selected U-Bootes. Indeed also the snorkel was a bonanza for the crew as well since the air aboard a U-boat was consumed both by the diesels and crew, while Carbon dioxide could be removed by special absorbers. Compressed air could be released in dire emergencies. Proper ventilation was always on the surface, but the snorkel allowed any U-Boats to make night crossing underwater (periscope depth) as the situation became tense in 1943, notably for passages into dangerous areas due to air and sea allied dominance, the channel, north sea and bay of biscaye.

The snorkel was invented in 1933 by Lt. Jan Jacob Wichers, and perfected with Lt. J C van Pappelendam, frirst tested on the submarine O-21 in February 1940. But R&D took years as the Schnorchel, inspired by Professor Walter and with Dönitz’s full support was made into a workable system by Ulrich Gabler and Hepp. The ealry version had two concentric and telescopic pipes working like periscopes, with the intake pipe provided a valve with a ball-shaped float preventing flooding. The other was for the exhaust gases but still could have water ingress. By June 1943 blueprints were ready and U 57, U 58 and U 236 started trials. They showed the cut-off valves failed, leading to much water ingress. U 235 and U 237 had the improved model, wider (220 mm (8.66in)) for 8,30 m high (326.77 inches) total and an exhaust 1,3 m (51.18in) lower than the air intake to avoid exhaust gases to be sucked back. In July 1944, some 120 snorkels were active moslty on Type VII and Type IX and probably a few Type VIIC/42 as well.

U-Boat commanders started to tinker themselves with the system and came out with a soltution, to order the air intake valve to be partially closed so the engines quickly sucked the air from the boat, so when the valve was fully opened again, fresh air rapidly filled the submarine, more quickly. The Snorkel made U-Boats true “submarines”, now avoiding to surface in the most challenging areas, or corssing threse at periscope depth. Sure, not designed to be fast underwater, the drag of the CT and all equipments on deck was still there, but diesel power was infintively greater than battery power at the time. This system could be use to load batteries as well, giving immense flexibility. But if production started in 1943,German indsustry hammered by allies raids could just not keep up and there were never enough. Snorkel-equipped U-Boats were given to experienced captains. On the long run, yards swapped to integrated this feature early on, as when fitted on an existing U-Boat, it required a major reconstruction, making it unavailmable for many months. And this added to the already tense workload of shipyards.

It was not perfect either: In rough seas the system would automatically close the intake valve, and thus, the diesels started to suck the air out from the pressure hukk, with a drop in pressure causing massive discomfort to the lungs and ears. Practical speed at the best of times was only 6 knots, comparable to the electric motors due to the constrictions of the system compared to the air intakes available when surfaced to the diesels and the drag.

Radars

Metox (1942)

The first system mounted on serial VIICs in 1942 onwards was the German Metox radar warning device. Originally it camed from a French inventor, Metox Grandin, which developed a system for monitoring radio signals with wavelengths between 1.3m and 2.6m, and thus, capable of detecting radar signals with the same wavelengths. This was simple wooden cross-shaped support for the antenna. It was adopted and deployed largely from Augyst 1942 but soon nicknamed “Biscaya-Kreuz” after the dangerous bay of biscaye, U-Boote graveyard of 1943. In fact captains refused to be deployed there if their sub was not equipped with the Metox antenna.

The first was built in occupied France at Metox & Cie, as a simple passive radar called FuMB NVK R600 A type, fitted with the FuMB Ant 2 antenna. Tests showed it could also betray the position of a U-boat as it emitted some radiation that could be detected by an aircraft below 500m (1650ft) from 22km (12nm), or as far away as 46.3km (25nm). However initially the Metox was really useful in poor visibility and by night as it could detect emissions from 62 to 264 HZ at a range of up to 80km (45nm). A replacement was needed in 1943 as the allies deployed their new centimetric-band radar, which the Metox could not detect.

FuMB4 Samos (Late 1942)

Deployed from October, it had a wavelength of 157–333cm in the 87–70 MHz band.

FuMB Ant–3 Bali (April 1943)

This model had a dipole antenna.

FuMB8 Zypern (Summer 1943)

Called W. Anzg. 1 ans its successor the FuMB9 Zypern 2 (wavelength 118–192cm, frequency 156–254 MHz) could be combined with the Fu MB Ant 3 Bali and Timor antenna.

FuMB 10 Borkum (later 1943)

Thus model introduced in late 1943 had a wavelength 75–300cm, frequency 100–400 MHz and combined well with the Bali and FuMB Sumatra antennas as well as the FuMZ 6 amplifier.

Still, R&D and production had been relocated to Germany for security reasons and German scientists worked on a new model, while claiming that a radar operating on a 10cm wavelength was impossible. Konteradmiral Ludwig Stummel working with the Abwehr, Kriegsmarine section, proved them wrong after interrogating captains that consigned in their logs radar emissions from further away or captured one from the RAF when the aircraft was shot down, the ‘Rotterdam Gerät’.

FuMB7 Naxos (winter 1943-44)

It was introduced from October 1943 with a range of 5,000m (27 nm) with a manually-rotated FuMG Ant 1X antenna, NVK Telefunken (from October 1943). By March 1944 it was combined with the FuMB antenna as the Cuba 1 for a range of 20km (11nm) to detect 8–12cm wavelengths radars. But when coupled with the Mücke antenna this went up to 50km (27mm).

FuMB 26 Tunis (late 1943)

The FuMB-26 Tunis was tuned to the 3 cm wavelengths and was able to detect US radar emissions. The Naxos system consisted of two leaf-like antennas in the middle of a parabolic mesh reflector. The Tunis was alternative to the Naxos in short supply.

FuMB 37 Leros (March-May 1944)

In early 1944 FuMB 35 Athos was coupled with the Bali to create the FuMB 37 Leros.

Dete Gerät (1941) & FuMO29 (1942)

All the above were only detecting radars, so when Dönitz met the engineers of companies working on such systems for the Luftwaffe, it became possible to create a proper search radar for U-boats. When available, their cost and size reserved them to the Type IXA U-Boat in late 1941. Two U-Boats tested it. The Dete was rather crude, with a 30° sector of observation, range of 7000m (3.7nm) and poor accuracy. A few Type VIIs had them in mid to late 1942. The later version Gerät 500 was redesignated FuMo29 and production ramped up. The first fitted woth the improved FuMO29 and its 82cm wavelenght were U623 and U231, both VIICs. It was improved leading to the FuMo30 with two rows of four dipoles each and larger bedframe. Whe fitted, it was retracted when not in use in a side stowage on the conning tower’s upper wall.

FuMO–61 Hohentwiel

Enters service in March 1944. It was derived from the FuG-200 used by the Luftwaffe with success. It was developed from the aircraft model by Dr Christ and Dr Müller from the existing FMG 40 Kurmark. Specs 550 MHz, wavelength 56cm, peak power 30 kW, range 10km (5.4nm), accuracy 300m (1000yds). U 763, a Type VIIC, was the first equipped with it for a full campaign before adoption at large. However by 1944, air raids ramped production so the number of sets available were always low. It was replaced by the FuMO65 Hohentwiel U 1 which had a FRQ of 110–160 MHz or 25–575 MHz and ultimately the late 1944 to early 1945 FuMO84 Berlin U 1 with a 9cm wavelength, 3300 MHz frequency, and peak power of 20 kW. They were stored in a watertight mast in the conning-tower.

Sonars

Gruppenhorchgerät

The GHG was an early acoustic system, a hydrophone array used on all models, including the Type VII. It was developed in WWI already following Pierre Curie discovery in 1880 using the piezoelectric principle. Atlas Werke AG in Bremen and Electroacustik (ELAC) in Kiel worked on transducers, detectors and amplifiers and found the best being the Seignette crystal formed from a mixture of different salts. From 1935, crystal receivers were permanently installed on German submarines.

The GHG was the final product, GHG made of two groups of 24 sensors, one on each side of the boat. Each sensor had a tube preamplifier. These 48 low frequency signals were routed to a switching matrix and the sonar operator could determine the side and direction of the sound source. To improve resolution, a frequency of 1, 3 and 6 kHz could be setup. There was however a dead zone of 40° fore and aft, but range was 20 km to individual ships and 100 km against a full Convoy. The Search area was 2 × 140° with a resolution of less than a degree at 6 kHz, 1.5° for 3 kHz, 4° for 1 kHz and without crossover 8°. The Royal Navy in May 1942 captured a submarine and its ELAC equipment. Later the Balkongerät was tested on U-194 in January 1943 and installed a few Type VII/42 but became standard on the Type XXI.

Balkongerät

This ancestor of the linear bow arrays of modern western sonars, these models had much greater performance than allied sonars due to their perculiar design philosophy, for long range target aquisition. They were both were low frequency for long range instead of high frequency for good spatial discrimination like speed and direction on allied sonars. Their detection range could be as long as 30,000 yards in good conditions. This system consisted of a passive acoustic echo chamber enabling multiple targetting for attacks. It was born from the need to do better than the GHG, unable to be used while cruising on the surface due to the diesels, nor even at periscope depth with an optimum operating modus below 20 meter at 3 knots.

The Balkongerät (or lit. “balcony-device” given its looks) was developed, fixed-mounted at the chin a submarine, the spot with less interference from surface noise, but leaving a dead spot towards the stern. This Balkongerät was tested on U-194, a Type IXC/40, in January 1943. It was installed on a few chosen Type VIIC/42 before beng adopted as standard for the Type XXI.

⚙ Type VIIC/42 specifications
Displacement	769 tonnes surfaced, 871 tonnes submerged, 1070 tonnes total
Dimensions	67,10 x 6,20 x 4,74 m
Propulsion	2x diesels 3200 hp surfaced+ 2 EM, 750 hp sub.
Speed	17.7 knots surfaced, 736 knots submerged
Range	8500 nm at 10 kts surfaced, 80 nm underwater at 4 kts
Armament	1x 8,8cm/45 deck gun+ 4 bow, 1 stern TTs (14) or 26 TMA mines
Max depht	c250 meters (820 feet)
Sensors	GHG, see notes
Crew	44-52

Appearance

Conning Tower symbols – Pinterest.

Planned construction

Ordered from Howaldtswerke, Hamburg as Werk 849 on 17 April 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 850 on 17 April 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 168) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 169) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 170) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 171) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 172) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 173) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 174) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Kriegsmarinewerft, Wilhelmshaven (Werk 175) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 810) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 811) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 812) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 813) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 814) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from H C Stülcken, Hamburg (Werk 815) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 529) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 530) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 531) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 532) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 533) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 534) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from AG Neptun, Rostock (Werk 535) on 17 April 1942. Construction suspended on September 30, 1943, and cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 850 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 851 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 852 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 853 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 854 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 854 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 855 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 855 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 856 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 857 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 858 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 859 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 732 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 733 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 734 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 735 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 736 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 737 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Hamburg as Werk 738 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 237 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 238 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 239 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 240 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 241 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Nordseewerke, Emden as Werk 242 on 17 Apr 1942. Laid down at an unknown date, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 249 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 250 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 251 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 252 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 253 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from Howaldtswerke, Kiel, Emden as Werk 254 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1610 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1611 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1612 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1613 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1614 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered from F Schichau GmbH, Danzig as Werk 1614 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 87 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 88 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 89 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 90 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 91 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered Vegesacker Werft, Vegesack, Danzig as Werk 92 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 509 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 510 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 511 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 512 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 513 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flensburger Schiffsbau, Flensburg as Werk 514 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 359 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 360 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 361 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 362 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 363 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 364 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 365 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 366 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 367 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 368 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 369 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 370 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 359 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 360 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 361 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 362 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 363 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 364 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 365 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 366 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 367 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 368 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 369 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Flender-Werke AG, Lübeck as Werk 370 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 273 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 274 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 275 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 276 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 277 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 278 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 279 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 280 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 281 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 282 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 283 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 284 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 285 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 286 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 287 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 288 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 289 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 290 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 291 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 292 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 293 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 294 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 295 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 296 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 297 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 298 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 299 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 300 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 301 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 302 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 303 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 304 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 305 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 306 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 307 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 308 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 309 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 310 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 311 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 312 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Blohm & Voss, Hamburg as Werk 313 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 167 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 168 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 168 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 169 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 170 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 171 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 172 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 173 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 174 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 175 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 176 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 177 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 178 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 179 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 180 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 181 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 182 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Danziger Werft AG, Danzig as Werk 183 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Kriegsmarinewerft, Wilhelmshaven as Werk 176 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Kriegsmarinewerft, Wilhelmshaven as Werk 177 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Kriegsmarinewerft, Wilhelmshaven as Werk 178 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Kriegsmarinewerft, Wilhelmshaven as Werk 179 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Howaldtswerke, Hamburg as Werk 851 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Howaldtswerke, Hamburg as Werk 852 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Howaldtswerke, Hamburg as Werk 853 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Howaldtswerke, Hamburg as Werk 854 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Germaniawerft AG, Kiel as Werk 740 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Germaniawerft AG, Kiel as Werk 741 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Germaniawerft AG, Kiel as Werk 742 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at Germaniawerft AG, Kiel as Werk 743 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1616 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1617 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1618 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1619 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1620 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1621 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1622 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1623 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1624 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1625 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1626 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1627 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1628 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1629 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1630 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1631 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1632 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Ordered at F Schichau GmbH, Danzig as Werk 1633 on 17 Apr 1942. Never laid down, cancelled on November 6, 1943.

Read More/Src

Books

Köhl, Fritz and Niestle, Axel. Vom Original zum Modell: Uboottyp VIIC. Bernard & Graefe Verlag, 1997.
Morris, Simon. An Illustrated Guide To U-Boat Research. 2012
Rössler, Eberhard. Die deutschen U-Boote und ihre Werften. Bernard & Graefe Verlag, 1990.
Rössler, Eberhard. The U-Boat: the Evolution and Technical History of German Submarines. Cassel 1981.
U-Boot Im Focus Edition 2. Luftfahrtverlag-Start, 2007.
Rössler, Eberhard. Die deutschen U-Boote und ihre Werften. Bernard & Graefe Verlag, 1990.
Nowarra, Heinz J.. Grey Wolves of the Sea: German U-Boat Type VII. Schiffer Military History, 1992.
Showell, Jak P. Mallmann. U-Boats In Camera. Sutton Publishing, 1999.
Stern, Robert C.. Battle Beneath The Waves. Arms & Armour, 1999.
Wetzel, Eckard. U 995: Das U-Boot vor dem Marine-Ehrenmal in Laboe. Karl Müller Verlag.
Wiper, Steve. Warship Pictorial #27: Kriegsmarine Type VII U-Boats. Classic Warships Publishing, 2004.

Links

an_illustrated_guide_to_uboat_research.pdf
uboat.net/ VIIC/42

Model Kits

None.