[Kapitän]

Originally Posted by Kapitän

Started new career in August 2019 to commemorate the beginning of WWII, 80 years before ...

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Friday, 5 March 1943 - Kiel

1506 - Arrival at Kiel Kriegsmarinewerft - Degausing

(The unfinished) Aircraft Carrier Graf Zeppelin and Heavy Cruiser Gneisenau (historically, was in Gotenhafen at the time) are in Kiel.

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B.d.U. HQ moves from Paris to Berlin, Hotel am Steinplatz (until 12/43).

British bombers attack the Krupp works at Essen, Germany; This is the Allies' first attack on this industrial region, which started what the Allies called the Battle of the Ruhr. This attack also sees the first successful use of "Oboe", an aerial blind bombing targeting system.

Auxiliary Aircraft Carrier USS Bogue departs Argentia, Newfoundland, bound for mid-Atlantic rendezvous with eastbound Convoy HX.228.

Tirpitz completes post-refitting trials in Drontheim.

U 333 (Oblt. Werner Schwaff; in deputize for "Ali" Cremer in hospital) was attacked by enemy aircraft at night without previous radar in BF 5897. Slight damage. Aircraft was shot down in flames.

U 445 (Oblt. Heinz-Konrad Fenn) sighted outward bound convoy at 1215 in CG 9577. Contact was lost after hydrophone activity accompanied by bombs and depth charges lasting 12 hours. Very heavy air and surface reconnaissance in the area off Gibraltar.

Our own aircraft sighted Gibraltar convoy at 1830 in CG 4611, course 60°, speed 7.5 knots.

U 183 (Korvkpt. Heinrich Schäfer) reported Swedish steamer showing lights on a course of 70° in DM 7527. In spite of clear orders the boat requested permission to attack. It was accordingly corrected. The ship was later confirmed to be an Argentinean vessel.

Situation Cape Town:
U 509 (Kptlt. Werner Witte) confirmed westbound traffic during the day and on moonlit nights in GR 6720. Slight possibilities for action, owing to air and land observation. Triple and single miss on steamers of 7,000 and 2,000 GRT. Subsequent passage to KY 4350.
U 516 (KrvKpt. Gerhard Wiebe): Nothing sighted in KZ 43 and 19 or from KZ 1781 to 1591 during a stay of several days. A modern passenger steamer, protected by corvettes, course 240° was sunk in KZ 1791 at 27.2. Size 10,000 GRT. Aerial activity up to 100 sea miles from land. Pieces of wreckage were rammed during patrol in KZ 1690 and KZ 2470. Withdrawn at the moment owing to oil tracks.

As more boats are to operate simultaneously in the area off the American coast, U 172 (Kptlt. Carl Emmermann), U 515 (Kptlt. Werner Henke) and U 513 (KrvKpt. Rolf Rüggeberg) already in CD are to be retained and distributed in the following order to the temporary ops. area CD 20, CD 30 and CD 40. As soon as the boats, also intended for this, arrive further movement is to take place. U 130 (KrvKpt. Ernst Kals) and U 159 (Kptlt. Helmut Friedrich Witte) are to make for CA 50 also U 106 (Kptlt. Hermann Rasch; ex Oesten) is to replenish supplies from "Milkcow" U 461 (Kptlt. Wolf-Harro Stiebler). 6 boats, therefore, are disposed for this operation. U 521 (Kptlt. Klaus Heinrich Bargsten) is also to take on supplies from U 461 and proceed to the east to reinforce the Group "Tümmler". U 461 has given U 106, 180 cubic meters of fuel and U 521, 102 cubic meters. The tanker is empty and is on the return passage.

U 648 (Ltnt.z.S.d.R. Peter-Arthur Stahl) undergoes Final Repairs at Blohm & Voss shipyard Hamburg.

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RST
KorvKpt.& Cmdr. U 115

Started new career in August 2019 to commemorate the beginning of WWII, 80 years before ...

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U 115
- KTB -
First War Patrol
(17th war patrol overall)

Saturday, 6 March 1943 - Kiel Kriegsmarinewerft

Final Adjustments and Pre-War Patrol Preparation:

- Loading of Fuel: 441t => 510cbm (at 865kg/m³) - 95 on gauge => 100%.

- Trimming trials in Kiel harbor.

Daily Op.-Briefing:

A) 1) The systematic evaluation of the English U-boat situation for the month of January and the beginning of February is reassuring, in view of the strong suspicion that the enemy had broken down our codes or otherwise obtained exceptional knowledge of our operations. (compare the English estimates of U-boat positions, confirmation of the facts accessible to the English, wireless bearings, sightings, U -boat attacks, a/s radar, also information obtained after the return of a number of U-boats.)
Except in the case of 2 - 3 unexplained incidents, English information from the facts accessible to him of U-boat positions, and plots of the boats, can throughout be traced to an explainable combination of facts. The most important revelation - confirmed almost without a doubt - was, that the enemy was able, with the help of a/c radar, to intercept U-boat dispositions with great accuracy - adequate for the successful evasive action of his convoys. As always, our countermeasures limp several weeks behind this kind of new enemy practice because:

a) His evasive measures are obvious, only after constant use, partly after receipt of English wireless messages (Special Radio Intelligence messages) not solved for weeks afterwards.
b) Reports of confirmed wireless location of U-boat dispositions, are rarely received by W/T, their use is not apparent until the operational survey and Commander's oral report.
c) The technical possibilities of "ASV" location (simultaneous confirmation of several targets at long range and thereby the simultaneous interception of several boats in one disposition) was still unknown.

A) 2) The fact perfectly corroborated by the increasing appearance of the additional word "radio located" in English U-boat situation (reports) of confirmation of U-boat dispositions by a/c radio location, meant an uncomfortable complication of the method used up to now, of intercepting convoys by patrol lines. As, in many cases, the inadequate number of U-boats in the patrol channels cannot be dispensed with.

a) The boats are ordered to submerge for about 30 minutes on confirmation of a/c radar. (Stipulation for the effective execution of this measure is the presence of a constantly used Fu.M.B. in good working order. The Fu.M.B. aerials at present in use in the ops. areas are however not practicable in all weather conditions. An alteration will not be made until the beginning of March, the time of the equipping of boats with fixed Fu.M.B. cable and round dipole.)
b) Avoid all unnecessary waiting in patrol lines before the presumed convoy passage time. (Disposition of the groups: "Neptun", "Ritter", "Burggraf", "Neuland"). These groups were to proceed on a westerly to southwesterly course on the convoy routes as far as the area of Newfoundland Bank "Harken". The passage speed was for the most part very small in the bad weather conditions generally prevailing; the disposition could almost be considered stationary in view of the long range of the "ASV" apparatus and the high speed and radius of action of English a/c. Up to now no better method has been tried. All other dispositions, i.e. the indiscriminate, unsystematic spreading out of boats in a certain area, ("castor sugar") have the disadvantage of too large spaces between the individual boats. After the non-interception of a convoy by such a disposition there is always the riddle what's to be done. The required certainty is lacking in a clear lineal disposition in any case up to a certain point (adverse weather conditions, periods of fog excepted), that the convoy has not sailed through the disposition area, that then, an alteration of the area and method is necessary.

U 648 (Ltnt.z.S.d.R. Peter-Arthur Stahl) undergoes Final Repairs at Blohm & Voss shipyard Hamburg.

RST
KorvKpt.& Cmdr. U 115