[Kapitän]

Originally Posted by Kapitän

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)

Friday, 25 June 1943 - West of the Cape of Good Hope -

0003 - T=20. Battery 62.9%, Compressed Air Supply 285Atü, CO₂ 1.2%.

0053 - Surfaced from S-Tiefe after 1h 10min. and 3.4nm. - Weather and Sea unchanged.

0057 - Boat ventilated and Compressed Air Supply filled.

0058 - Charging batteries (62.9%): Stbd.-Diesel Charging 496RPM; Port-Diesel Propulsion 285RPM/8kn.

0115 - Qu.5562GR bottom right - FuMB-Detection in 87°true, E=8700. Interrupting charging process (65.7%). Shortly after an airplane approaching from 87°true, is already fairly close. Going to A.K. and hard to port. The airplane (Hudson or Ventura) is dropping 3 bombs behind the boat and flies off on course SW.

Pressure Hull sustained 2% damage (Total 13% => 87% of 230m => 200.1m safe diving depth).

0118 - Boat stays surfaced. On course 270°. 2xH.F.-Ahead

0140 - Charging batteries (65.7%): Stbd.-Diesel Charging 496RPM; Port-Diesel Propulsion 285RPM/8kn.

0147 - Port-Diesel Propulsion 375RPM/10kn.

0157 - Qu.5561GR bottom right - Hudson or Bolo in 164°true, is already fairly close, flying over the boat without attacking (no FuMB/Magic Eye detection). The airplane is approaching the boat again from NW. Interrupting charging process (70.0%) and going to A.K. 2 bombs fall wide to stbd., no damages. The airplane flies off on course ENE, and is out of sight at E=4000. Suspect that the A/C had no radar fitted, which may explain not sighting the boat at first and the inaccurate bomb attack.

0212 - Boat stays surfaced. Charging batteries (70.0%): Stbd.-Diesel Charging 496RPM; Port-Diesel Propulsion 285RPM/8kn.

0228 - Port-Diesel Propulsion 375RPM/10kn.

0230 - Batteries charged 75% (74.3% acc. gauge).

0415 - Port-Diesel Propulsion 285RPM/8kn.

0445 - Qu.5551GR - bottom right - Batteries fully charged: 2h 33min. for 30%). 2x1/3-Ahead, 285RPM, 10kn. On course 180°.

0505 - Outgoing F.T.: To B.d.U.:
Continued from F.T.1155/24: Steamers leaving Cape Town run from Qu.5621GR center left, on course 200° to Qu.5646GR centr left. From 24.6., 1500 until 25.6., 0200, U-Hunt with A/C and up to 10 escorts. Damage to hull, safe diving depth 200m. On 24.6., 2215, shot down one Wellington bomber in Qu.5644GR top right. Still have 2 EtoFat and 460cbm. Continue outbound transit acc. Op.-Orders. SSE4/3, clear, visibility 4-5nm, >1000mb. - RST -

1058 - Qu.5851GR - On course 130°.

1200 - Qu.5855GR - Days Run: 163.6nm - ↗ 147.8nm (13h 23') - ↘ 15.8nm (10h 37')
Total: 9058.7nm (51tg 22h) - ↗ 8672.8nm (45tg 19h 52') - ↘ 385.9nm (6tg 02h 08')
Course 130°; 459cbm (2cbm in 24h); Battery 100%; 2xEtoFat; 8xBold.
SSE4/3, clear, visibility 4.5nm, >1000mb (Weather & Sea unchanged in 37h) - Early Morning Dawn -

1209 - Incoming Radio Reports:

From O.K.W.:
a) On 22 June, 60 British Lancaster bombers attacked factories at Friedrichshafen. The enemy had planned to attack a factory producing radar parts, but in actuality it is manufacturing parts for V-2 rockets.
b) Riots fueled by racial tension are finally under control in Detroit, Michigan, after three days of violence committed by both whites and African-Americans. During this period, 34 were killed (9 whites, 25 African-Americans), about 500 were wounded (about 75% African-Americans), more than 1,800 were arrested (about 80% African-Americans), and US$2,000,000 worth of damage were done to property.

From B.d.U.:
After an evaluation of the latest experiences on the Biscay passage, the boats receive the following directions in Standing Order No. 13, issued on 22 June 1943.
A. The procedure of U-boats in approach and operational areas depends to a great extent on the appearance, behavior and numerical deployment of the enemy U-boat chaser planes equipped with radar apparatus. Attacking tactics, time and place of the enemy operational concentration constantly changes and this, as soon as known, necessitates an alteration in the tactics of the U-boats and a continuous unavoidable amendment of the orders accordingly.
As far as possible, a certain report of enemy air force dispositions in the North Atlantic will be transmitted regularly.
B. The greatest danger to the U-boat lies in the surprise attack of aircraft locating by radar. Danger of surprise consists:
By day: In medium to heavy cloud, low-lying cloud, medium to poor visibility.
By night: In clear peaceful weather, bright moon light, phosphorescence on the sea.
Unfavorable for an attacking aircraft is: clear cloudless weather with good visibility or thick fog by day; further: changeable, stormy nights, in which the rough confirmation of the boat is possible with the radar apparatus, but the location of its exact position, speed and course and a therefore precise placing of the bombs, is greatly complicated.
C. The following principles are laid down:
Proceed with greatest caution on passage and in the waiting position in the operations area. Avoid losses.
If operations on a decided target are being carried out, then act with dash and determination, in spite of threatening aircraft activity, remain on the surface and beat off aircraft if necessary.
See also Standing Order No. 181, Section C and Appendix 1.
It is ordered in this connection:
1) a) On the out and return passage in the Biscay area as far as 18 W and outward passage Home Waters to North Atlantic as far as upper third of Naval Grid AL, boats must proceed principally submerged. Surface only to recharge batteries and ventilation of the boat generally only by day.
If daylight passage appears inadvisable owing to especially strong air activity, unfavorable visibility and defence conditions, proceed at night (See Section B).
If the visibility is sufficiently good to make surprise impossible, surface passage by day is permissible. Then, however, proceed at high speed, to gain distance.
1) b) On putting in routes, boats are to proceed on the surface. Submerge only in the event of acute danger from the air. Boats put out in the morning and put in the evening, so that the approach routes are passed during the daytime.
See Standing Order No. 483, Section D, para. 1).

- to be continued -

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)

Friday, 25 June 1943 - West of the Cape of Good Hope -

- continued from 25 June, 1209 -

1215 - Incoming Radio Reports:

From O.K.W.:
a) On 24 June, RAF bombers attacked Elberfeld in the Ruhr region.
b) Commanding officer of the 4th Group of the Nachtjagdgeschwader 5 wing, Heinrich Prinz zu Sayn-Wittgenstein flew the Bf 110 nightfighter for the first time, discovered technical issues, and returned to flying his usual Ju 88 aircraft, in which he shot down four British Lancaster bombers. His victories now stand at 35.

From B.d.U.:
a) To all boats: Status report about development of new boat type XXI and Walter boats.
b) As a result of the last traffic report the Cape Town boats at present refueling from the tanker "Schliemann" are ordered on 23 June to take up position in the following operational areas: U 178: western half, U 196: eastern half of KE. Center point : narrows of Mozambique channel. U 198: northern half, U 197 southern half of area off Durban, depth 800 sea miles. U 177: area round KQ 92, depth 400 sea miles. (S. of Madagascar), U 181: area round KG 83, depth 400 sea miles (Mauritius Islands). U 115: Continue to supply point acc. Op.-Orders. All boats will be informed of the presumed traffic situation in their areas.

1323 - Sunrise. Weather and Sea unchanged in 38.5h.

1827 - Qu.8315GR top center left - Magic Eye Detection. Shortly after, a Catalina in 297°true, E=9000, is positioned in Qu.8311GR bottom left, on course SSW and turns toward the boat in 275°true and E=9000.

1829 - "ALARM!". At T=55, 2 bombs and at A-Meter 1 more. No damages. Suspect that the A/C was not fitted with radar, but sighted the boats keel water.

1842 - Setting for Reception Depth.

1851 - T=20. Battery 97.0%, Compressed Air Supply 285Atü, CO₂ 1.1%.

1859 - Surfaced from S-Tiefe after 30min. and 1.6nm. - Weather and Sea unchanged.

1902 - Boat ventilated and Compressed Air Supply filled. 2x1/3-Ahead, 285RPM, 10kn.

2002 - Qu.8319GR top center left - FuMB-Detection in 28°true, E=13000. Giving order to dive.

2003 - Right during the watch change, airplane (is a Wellington) in 28°true, E=9000, direct approach out of the sun. "ALARM!". During the diving process no bombs.

2005 - 1 Wabo and 3 more until 2010 - no damages.

2017 - Setting for Reception Depth.

2026 - T=20. Battery 97.0%, Compressed Air Supply 290Atü, CO₂ 1.1%.

2032 - Surfaced from S-Tiefe after 30min. and 1.5nm. - Weather and Sea unchanged.

2036 - Boat ventilated and Compressed Air Supply filled. 2x1/3-Ahead, 285RPM, 10kn and at 2041 - 2xH.F.

2050 - Qu.8319GR bottom right - Airplane in 005°true, E=5300, direct approach out of the sun, it's a Hudson or Ventura (No FuMB/Magic Eye Detection). Evading with A.K. hard to port. 1 bomb is dropped wide to port - no damages. Airplane flies off on course SSW, boat going back to general course.

2057 - Qu.8319GR bottom right - Airplane in 255°true, E=6700, direct approach, it's a Wellington (No FuMB/Magic Eye Detection). Evading with A.K. hard to stbd., machine-gun fire.

2058 - After the fly-over, "ALARM!". Airplane turns around at E=3400. At T=40, 2 Wabos behind the boat - no damages.

2101 - At A-Meter another 2 Wabos - no damages. Boat going back to general course.

2112 - Setting for Reception Depth.

2121 - T=20. Battery 94.0%, Compressed Air Supply 285Atü, CO₂ 1.1%.

2128 - Surfaced from S-Tiefe after 30min. and 1.6nm. - Weather and Sea unchanged.

2132 - Boat ventilated and Compressed Air Supply filled. 2x1/3-Ahead, 285RPM, 10kn.

2133 - Qu.8351GR top left - Airplane in 21°true, E=8100, direct approach, it's a Sunderland (No FuMB/Magic Eye Detection).

2134 - "ALARM!". At T=35, 1 Wabo wide to Stbd. - no damages.

2138 - At A-Meter, 2 Wabos and again at 2139, 3 Wabos, and another 2 Wabos at 2141 - no damages.

2215 - At A-20. Setting for Reception Depth.

2222 - T=20. Battery 91.4%, Compressed Air Supply 270Atü, CO₂ 1.2%.

2228 - S-Tiefe. A Sunderland can be seen in 250°true, E=9800, on course 24°, is out of sight in 336°true, E=9700 (position is in Qu.8327GR bottom left).

2234 - Surfaced after 1h and 2.9nm. - Weather and Sea unchanged.

2235 - Boat ventilated.

2244 - Compressed Air Supply filled. 2x1/3-Ahead, 285RPM, 10kn, and at 2250, 2xH.F.

2302 - Qu.8351GR bottom right - FuMB-Detection in 215°true, E=14500. Giving the order to dive. Before closing the Conning Tower Hatch, can see a approaching in 215°true, E=8300.

At T=25, 1 Wabo behind the boat and at T=45, 1 more Wabo - no damages.

At A-10, 6 Wabos - no damges. Boat sinks to A+20 and can only be brought back up to A-Meter with 135rpm.

2307 - Sundown.

2333 - Back to Reception Depth. Battery 90%, Compressed Air Supply 290Atü, CO₂ 1.1%.

2341 - S-Tiefe. A airplane can be seen in 175°true, crosses the bow of the boat at short distance on course NNE.

2347 - Surfaced after 45' and 2.2nm. - Weather and Sea unchanged.

2350 - Boat ventilated and Compressed Air Supply filled. 2x1/3-Ahead, 285RPM, 10kn, and at 2255, 2xH.F.

RST
KorvKpt.& Cmdr. U 115