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Old 05-25-23, 07:24 AM   #440
Kapitän
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Default U 115 - First War Patrol (2nd leg) - Black May - New B.d.U.-Orders

Quote:
Originally Posted by Kapitän View Post
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)

Monday, 24 May 1943 - Southwest of the Cape Verde Islands

0400 - Qu.7443EJ - SSW5/4, medium swell, overcast, light haze, limited visibility, ~1000mb.

0745 - Qu.7488EJ - Crash dive for training. T=10 after 41 Sec.

1748 - A-Meter.

0800 - A-20.

0952 - Reception Depth. CO₂ 1.3%; Compressed Air Supply 260 Atü; Battery 80%.

1000 - Surfaced after 2h 15min. and 6.1nm.
Weather and Sea unchanged.

1005 - Boat ventilated and Compressed Air Supply filled. 2x225RPM/8kn.

1038 - Sunrise. Weather and Sea unchanged in 6.5h.

1104 - F.T. from B.d.U.: To all boats:

Orders were given on May 22nd as follows ("All Waves"):

(Message 1752):
The danger of being surprised by locating aircraft is very great, especially at night. The following orders are, therefore, given:
1) Procedure when approaching and returning from the Biscay area and approaching the area home North Atlantic as in Permanent Order No. 13.
2) Procedure in the operational area North Atlantic when cruising and stopping in position.
a) By night: One electric motor slow to half speed, other motor Diesel ready to start up. Boats ventilator switched off. Reason for this: To be able to confirm approaching aircraft by hydrophone. MG ready and manned.
b) By day: With higher cruising speed than before confirm that boat can be easily maneuvered and is able to dive.
c) If weather conditions are unfavorable by day and night proceed only underwater.
3) When contacting the enemy: Operations as before.

(Message 1769):
In almost every operation boats are seriously endangered by submerging in view of aircraft even when a safe depth cannot be reached before the bombs are released. It should be impressed on all Officers of the Watch that when the protective depth i.e. 80 to 100 m., can no longer be attained with certainty before bombs are released, i.e. always when the watch on the bridge is taken by surprise, it is best to remain surfaced and ward off the aircraft attack with Flak guns. We do not know how often loss has been caused by submerging too late. However, we do know that defense measures when surfaced have led to success in all cases reported.
Apart from this, the situation in the North Atlantic now forces a temporary shifting of operations to areas less endangered by aircraft. The following areas come into consideration: the Caribbean Sea, the area off Trinidad, the area off the Brazilian and West African coasts. It is, therefore, intended to operate primarily with VIIC boats in these areas, as far as permitted by the supply situation. If necessary, operational boats must also be sent in to supply other boats. With the boats at present in the North Atlantic, operations will be made against the traffic between USA and Gibraltar - as far as these boats are able to do this with their fuel. The North Atlantic cannot, however, be entirely denuded of boats. It is necessary, by means of single boats, to leave the enemy in ignorance as long as possible regarding alterations in tactics. For this operation in the North Atlantic boats are available now which cannot be sent elsewhere in view of their fuel supplies, and also boats coming from home waters for their first operations, which must be assigned the stay in the North Atlantic in spite of the difficult conditions. It is intended to attempt attacks on a convoy only under particularly favorable conditions, i.e. in the time of the new moon. The new moon period at the end of June is the first to come into consideration, since the boats at present in the North Atlantic are no longer operational enough. It will be necessary to assign several veteran boats for this as a support for the newer boats in the North Atlantic.
These decisions comprise a temporary deviation from the former principles for the conduct of U-boat warfare. This is necessary in order not to allow the U-boats to be beaten at a time when their weapons are inferior, by unnecessary losses while achieving very slight success. It is, however, clearly understood that the main operational area of U-boats is, as it always was, in the North Atlantic and that operations must be resumed there with every determination as soon as the U-boats are given the necessary weapons for this. Equipment with 2 cm., quadruples, which will begin as from June to an increasing degree will be the first step in this direction, equipment with Zaunkönig torpedoes (anti-destroyer) the second step, while improvement of location devices at the moment is still to be considered. It is, however, anticipated that after equipment with quadruples, i.e. from the Autumn, the battle of the North Atlantis will be completely resumed once more.
In the meantime it is essential that the morale of the men should not be affected by these temporary defensive measures, a task which requires full cooperation of the Commanding Officers, as well as the personal touch of the Commander in Chief of the Navy.

- signed - B.d.U. & Grand Admiral Karl Dönitz -

1200 - Qu.7729EJ - Days Run: 179.5nm - ↗ 173.4nm (21h 45') - ↘ 6.1nm (2h 15')
Total: 3674.8nm (19tg 22h) - ↗ 3533.7nm (17tg 19h 14') - ↘ 141.1nm (2tg 2h 46')
461cbm (2cbm in 24h); Course 161°; Battery 80%; 3xT-3, 2xEtoFat, 1xT-4; 9xBold; Weather and Sea unchanged in 8h.

1605 - Qu.7794EJ - WSW6/5, medium swell, partly cloudy, medium visibility, >1000mb.
Crash dive for training. T=10 after 39 Sec.

1608 - A-Meter.

1625 - A-20.

1807 - Reception Depth. CO₂ 1.3%; Compressed Air Supply 265 Atü; Battery 74.3%.

1815 - Surfaced after 2h 10min. and 5.8nm.
Weather and Sea unchanged since 1600.

1816 - Boat ventilated.

1821 - Compressed Air Supply filled. 2x225RPM/8kn.

2312 - Sundown. SW6/5, medium swell, partly cloudy, medium visibility, >1000mb, shifting South.

RST
KorvKpt.& Cmdr. U 115
Started new career in August 2019 to commemorate the beginning of WWII, 80 years before ...

+++++++

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

Tuesday, 25 May 1943 - South of the Cape Verde Islands

- 3rd week at sea completed -

0035 - Qu.1271ES - SSW6/5, medium swell, partly cloudy, medium visibility, >1000mb, shifting East.

0308 - Qu.1512ES - East6/5, medium swell, partly cloudy, medium visibility, >1000mb.

0700 - Qu.1557ES - Diving for torpedo maintenance and trial dive.

0707 - T=50. Beginning torpedo maintenance.

0758 - Tube I serviced.

0815 - Tube II pulled - Watch Change at 0811 -

0849 - Tube II serviced.

0940 - Tube III serviced (tubes I-III are T-3/Pi39H).

1031 - Tube V serviced (EtoFat/Pi39H).

1042 - Sunrise.

1122 - Tube VI serviced (T-4/Pi39H).

1130 - Reception Depth. Beginning of Trial Dive acc. B.d.U. Standing Order No.507 & No.308. 145rpm/3kn.

1150 - CO₂ Warning at 1.7% (after 4h 50min.).

1200 - Qu.1584ES - Days Run: 152.5nm - ↗ 133.2nm (16h 50') - ↘ 19.3nm (7h 10')
Total: 3827.3nm (20tg 22h) - ↗ 3666.9nm (18tg 12h 04') - ↘ 160.4nm (2tg 9h 56')
458cbm (3cbm in 24h); Course 161°; T=A+50; Battery 63%; CO₂ 1.8%; 3xT-3, 2xEtoFat, 1xT-4; 9xBold.

1216 - Boat is safe and secure at 2A-Meter. Setting for T=20 with 145rpm.

1227 - At A-Meter, 96rpm.

1231 - Boat rises to T=18.5m.

1234 - Boat is level at Reception Depth (140m in 18min. at 145rpm and 96rpm). Battery 61.5%; Compressed Air Supply 285 Atü; CO₂ 1.8%.

1239 - F.T. from B.d.U.: To all U-boat Commanders:

1) Our heavy U-boat losses in the last month are to be attributed primarily to the present superiority of enemy location gear and the surprise attacks from the air enabled by these. More than half of these losses have occurred by reason of their surprise tactics, on approach and return passage, as well as in the operational area in attack positions. The losses in attacks against convoys themselves were, however, slight except for one case in which conditions were particularly unfavorable. A part of these losses also occurred through air attack.
2) The present situation in regard to enemy aircraft and enemy location must be counterbalanced, through entailing other disadvantages, by special precautionary measures while proceeding and in waiting positions. Orders regarding this have been issued. I shall also come to further conclusions in the selection of operational area.
3) I am directing my whole attention to the improvement of our own location, anti-location means and Flak armament. This problem is being worked on everywhere with great concentration. Practical results will shortly be introduced for operations. Until then cruising and waiting must be carried out with skill and care, but actual attacks with the same tenacity as ever.

- signed - B.d.U. & Grand Admiral Karl Dönitz -

1240 - Surfaced after 40min. and 2.2nm since Etmal (Total: 5h 40min. and 15.7nm). Weather and Sea unchanged in 9.5h.

1242 - Boat ventilated and Compressed Air Supply filled. 2x225RPM/8kn.

1611 - SE1/1, partly cloudy, light haze, medium visibility, >1000mb.

1615 - Charging batteries (61.5%): Stbd.-Charging, 496RPM; Port-Propulsion, 285RPM/8kn.

1930 - Batteries charged => 3h 15min. for 38.5%. 2xSmall-Ahead/185RPM/7kn

1935 - Test Run of main diesels acc. B.d.U.-Standing Order No.510. - 285RPM/1/3-Ahead/10kn.

1940 - 375RPM/2xH.F./13kn.

1945 - 455RPM/Full-Ahead/16kn.

1950 - 496RPM/A.K./18kn/30min.

2020 - Reducing speed in speed settings of 5min. decrements.

2035 - 2x225RPM/8kn.

2311 - Sundown. Weather and Sea unchanged since 1611 (7h).

RST
KorvKpt.& Cmdr. U 115
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