Helmut Rosenbaum resurrected

[sublynx]

Originally Posted by Fahnenbohn

In reality, was the U-Boot's position given each 4 hours to BdU ? Or is it just for your personnal navigation book ?

Here's some war time rules on keeping KTB's:

http://www.uboatarchive.net/BDU/BDUOrder501A.htm

Thanks ninja turtle! Great to read and very interesting, especially as you compare your patrols to the real patrols made by U-2

[Becker67]

Originally Posted by sublynx

Here's some war time rules on keeping KTB's:

http://www.uboatarchive.net/BDU/BDUOrder501A.htm

Thanks ninja turtle! Great to read and very interesting, especially as you compare your patrols to the real patrols made by U-2

Been looking for stuff like this - thanks for the linkage

[ninja turtle]

Kapitänlutnant: Helmut Rosenbaum
Name: U-73
U-Boat type: VIIB
Flotilla: 7th
Emblem: Tree / Axe with USA / Shield with castle and bird of prey. None of these emblems exist within SH3 so decided to use the emblem for 7th FLotilla.

Historical Departure: 7 Aug 1941, St. Nazaire.
In-game Departure: 1 Aug 1941, St. Nazaire.
Historical Arrival: 7 Sep 1941, St. Nazaire.
In-game Arrival: 7 Sep 1941, St. Nazaire.
[See note below after patrol KTB]

The dates I am starting are actually from U-73's 4th patrol as this patrol was the nearest to the start of a month as SH3 always starts on the 1st with a new career.

U-73 patrolled the area of grid AL during this patrol with Wolfpack Grönland, consisting of the additional 20 boats: U-38, U-43, U-71, U-77, U-82, U-84, U-96, U-101, U-105, U-129, U-202, U-206, U-501, U-553, U-563, U-567, U-568, U-569, U-652, U-751.

Historically, out of the 21 boats within this Wolfpack only 7 were successful in sinking targets, with 1 damaging another within my patrol time-scale. Zero U-boats were lost between 1st Aug and 7th Sep, although U-501 was lost on 10th Sep 1941 (just after U-73's return to St, Nazaire).

All sources as per post #1.

[ninja turtle]

War Patrol 1

U-73, 7th/13th Flotilla

Kommandant: Kapitänleutnant z. s. Rosenbaum

Beginning: 1.8.1941
Ending: 7.9.1941

From: St. Nazaire

Mission Orders: Patrol South of Iceland as part of Grönland Wolfpack

Loadout: 14 x T2 G7e torpedoes (including 2 x external reserves)

Deck Gun: 8.8cm SK C/35

Flak Gun: 2 cm FK C/30 Flakzwiling

News for July 1941: German forces occupy Minsk and surround Smolensk. Allies and Vichy French forces sign an armistice, bringing fighting in Syria and Lebanon to a close.

Monthly losses: 1 U-boat for 112,624 GRT.

4.8.41.

2113 N3, Sea 2, partial clouds, Vis. good
Escorted out of dock. Diesels KF.
2147 Released from escort. Diesels HF. Course: 208°.
2210 BF6517 BR Course: 270°.

5.8.41.

0000 BF6438 DBK: 27m.
0400 BF6419 DBK: 101m.
0800 BF5561 Test dive. Levelled at 80m. Electric motors KF. DBK: 129m.
0840 Surfaced. Diesels LF. Course: 256°.
1200 BF5557 DBK: 132m.
1600 BF5496 Course: 285°. DBK: 1000m.
2000 BF5449 Nothing to report.

6.8.41.

0000 BF5442 "
0400 BF4630 BL "
0800 BF4630 "
1200 BF4374 BL "
1424 Ship spotted on bearing: 29°. Heading: NE. Changed our course to 49°. Increased speed to GF.
1430 ID: Possibly a Steam Merchant, 7000 GRT. Heading: 40°. Speed: 4 knots.
1455 Battle stations for submerged attack. Target changed course to 15°. Looked to be zigzagging.
1510 Set up for bow attack. Target: Steamer, speed: 4 knots, target angle: red 90°, range: 800m, tube I depth: 4m AZ, aim-point: bow, tube II depth: 6m MZ, aim-point: centre.
Observations through periscope: Target zigzagging but not venturing too far from course of 40°.
1550 Torpedoes fired at respective aim-points, reticle 351°.
Impacts at 90 seconds and 114 seconds respectively.
Also fired tube III in haste in case tube II missed. This was an error on my part as it missed due to the target taking evasive action after the first two detonations.
1552 Steamer's stern gun commenced attack at our periscope. Lowered it immediately to avoid any damage and changed course to run parallel to target at electric motors GF to get ahead.
1600 Once we were out of danger from the stern gun, the periscope was raised and I could observe that the steamer was listing to starboard and obviously sinking. Surfaced.
After a few minutes after surfacing the steamer's stern slowly slipped beneath the surface.
1 x lifeboat seen. Provisions passed to survivors.
1800 Radio message received from BdU: "Confirmed sinking. British Steam Merchant Empire Endurance. 8570 tons. Cargo: Military stores. Crew: 94. Crew lost: 66."
2000 BF4251 BR Nothing to report.

7.8.41.

0000 BF4217 "
0400 BF4126 "
0800 BF4113 "
0952 Radio report: "Large convoy. Grid: BF14. Course: NE. Speed: 7 knots."
1. The distance and time taken to reach this convoy and to be able to attack using night-time cover would have meant attacking in shallow waters and very close to the English Channel, and therefore with limited escape options.
2. Assumed that the convoy would have protection by a number of destroyers.
3. Therefore decided to continue on original planned course and hunt other targets allowing us a greater chance of survival.
1200 BE3990 N3, Sea 2, partial cloud, Vis. very good
Course: 301°. Decided to travel on the surface during the day while the weather is clear, diesels HF in case we are surprised by aircraft, and at LF during the dark hours to conserve fuel.
1600 BE3951 Nothing to report.
2000 BE3596 "
2200 Reduced diesels to LF.
2304 BE3556 Ship spotted on bearing: 295° travelling towards our port stern. Heading: East. Increased diesels to AK and hard starboard to run parallel.
2310 Battle stations for submerged attack due to full moon and clear sky. Target: Steamer, speed 7 knots.
2315 Changed our course to 180° for a Green 90° attack, range: 800m, speed: 7 knots, torpedo depth: 5m AZ, aim-point: centre.
2335 Noticed a stern deck gun. Decided to use a single torpedo and then surface and use deck gun if necessary avoiding target's armament.
2340 Tube I fired. 40 seconds run then impact at centre. 45 seconds after impact, target was seen to be dead in water.
After it was clear that the deck gun was unmanned and the crew were abandoning ship, surfaced.
7 minutes and 15 seconds after impact the target slipped beneath the surface. Explosions heard. Possibly the boiler.
Provisions passed to survivors and ship's name called to us: Waynegate.
Set course to 299°.

8.8.41.

0000 BE3556 Radio message received from BdU: "Confirmed sinking. Waynegate. 4260 tons. Cargo: Coal. Crew: 41. Crew lost: 0."
0400 BE3510 BR Moon covered by cloud. Moved forward external reserve torpedoes into boat whilst conditions were favourable and night visibility sufficient.
40 minutes.
0800 BE3190 Nothing to report.
1200 BE3151 TL "
1600 AL9998 TC Course: 297°.
2000 AL9954 TL Nothing to report.
2200 NW5, Sea 4, clouds clear, Vis. good Change of weather.

9.8.41.

0000 AL9832 BR WSW 5, Sea 4, clouds clear, Vis. good Wind direction change.
0400 AL9580 TR SSW 5, Sea 4, clouds clear, Vis. good "
0600 Radio report from BdU to Grönland Wolfpack via U-206: "British Steam Trawler Ocean Victor sunk at 0528. 202 GRT. One torpedo hit. Sank immediately. AE8525."
0800 AL9540 Nothing to report.
1200 AL9431 BC "
1600 AL9173 "
2000 AL8238 BL "

10.8.41.

0000 AL5879 Vis. very good due to Icelandic sunset "
0400 AL5769 "
0800 AL5729 BL "
0900 WSW 7, Sea 4, clouds clear, Vis. very good Weather change.
1200 AL5477 TR Nothing to report.
1600 AL4556 "
2000 AL4510 "
2155 Radio report: "At 2140 enemy ship in grid AL4828. Heading: East. Speed: medium."
170km from our location. Potentially possible to overtake the target within 10 hours at diesels GF, assuming that the target's speed was 8 knots.
Changed course to 94°.

11.8.41.

0000 AL4279 Nothing to report.
0400 AL4531 TC "
0800 AL5413 "
1200 AL5434 TR "
1600 AL5516 "
1800 Course change: 148°. Intention: By midnight 12 August we should be ahead of the target on expected course line and will head west to intercept target using visual and hydrophone.
2000 AL5567 Nothing to report.
2340 E7, Sea 4, clouds clear, Vis. good Course change: 270°. Reduced diesels to LF.

12.8.41.

0000 Submerged to 60m for hydrophone check.
Nothing.
0100 Surfaced.
0400 AL5828 Radio message recieved from BdU to Grönland Wolfpack via U-568: "AE7665 British Corvette (Flower) HMS Picotee hit by single torpedo. Broke in two and sank immediately. 925 tons."
0500 Submerged to 60m for hydrophone check.
Nothing.
0600 Surfaced.
0800 AL5817 Changed course to 90° and increased diesels to AK. Thoughts that we had missed the target. Tried to overrun on assumed course.
1200 AL5837 Nothing to report.
1600 AL6727 "
2000 NE7, Sea 5, clouds clear, Vis. very good Fuel close to 60%. Decided to stop the chase. Fuel too low to continue at AK. Target might have changed course.
Patrolling grids AL9-7.
Course change: 137°. Diesels at LF.

13.8.41.

0000 AL6873 Nothing to report.
0400 AL9220 "
0800 AL9276 BR "
1200 AL9614 "
1600 E7, Sea 5, clouds overcast, lightning in distance, Vis. fairly good Submerged to 60m to give watchcrew some respite due to change in weather. Continuing until batteries and CO2 levels become too low.
2000 AL9681 TL Nothing to report.

14.8.41.

0000 AL9684 TC "
0400 AL9688 TL E7, Sea 6, clouds overcast, Vis. poor Surfaced.
0800 AL9960 Nothing to report.
1200 AL9997 New course: 275°.
1300 Clouds clearing, Vis. good
1600 AL9970 Nothing to report.
1700 New course: 289°.
2000 AL9859 BR SE7, Sea 5, clouds clear, Vis. good Nothing to report.

15.8.41.

0000 AL9842 "
0400 AL9734 TL "
0800 AL9470 "
1200 AL8567 S6, Sea 4, clouds clear, Vis. good "
1600 AL8518 W6, Sea 4, clouds clear, Vis. good "
2000 AL8431 "

16.8.41.

0000 AL8172 Submerged to 60m for respite and to save on fuel.
0400 AL8172 TL Nothing to report.
0800 AL8147 Surfaced.
1100 W7, Sea 5, clouds overcast, rain and heavy fog, Vis. poor Submerged to 60m.
1200 AL7253 Nothing to report.
1600 AL7228 "
2000 AL7227 "

17.8.41.

0000 AL7216 "
0400 AL7210 S7, Sea 5, clouds overcast, rain and heavy fog, Vis. poor Surfaced to replensih air and recharge batteries.
0710 Batteries recharged. Submerged to 60m. Electric motors at KF.
0800 AL7211 BR Nothing to report.
1200 AL7211 TL "
1300 New course: 260°.
1600 AL7133 Nothing to report.
2000 AL7132 "

18.8.41.

0000 AL7132 BL S7, Sea 5, clouds overcast, heavy rain and fog, Vis. poor, lightning in distance Battery charging.
0106 Batteries recharged. Patrol report sent to BdU: "Fuel almost at 50%. Weather conditions very poor. At KF fuel should reach St. Nazaire surfaced and submerged. 10 torpedoes including reserves."

0120 Radio message received from BdU: "Return to St. Nazaire. Economise fuel. Use torpedoes on targets of opportunity."
Submerged to 60m. New course: 107°.
0400 AL7130 Nothing to report.
0800 AL7130 BR "
1200 AL7139 "
1600 AL7217 "
1710 W6, Sea 6, overcast, rain and heavy fog, Vis. very poor, lightning Surfaced to recharge batteries and renew air.
Radio message received from BdU via U-38: "AD7969 0250 fired two torpedoes at Steam Merchant Longtaker. Sank within one minute."
1804 Batteries recharged. Submerged to 60m.
2000 AL7217 Nothing to report.

19.8.41.

0000 AL7218 BC "
0400 AL7243 "
0800 AL7251 "
1200 AL7254 E5, Sea 4, overcast, lightning in distance Vis. fairly good, medium fog Surfaced. Diesels at HF. Recharging batteries. Continued on surface whilst low visibility reduced threat from enemy aircraft.
1306 Batteries recharged.
1600 AL7293 TL Nothing to report.
2000 AL8187 Reduced engines to KF in order to conserve fuel.

20.8.41.

0000 AL8423 TL E4, Sea 3, overcast, medium fog, lightning in distance, Vis. poor Nothing to report.
0400 AL8431 "
0800 AL8436 "
1200 AL8517 "
1600 AL8543 TL "
2000 AL8551 Submerged to 60m for hydrophone check due to limited visibility.

21.8.41.

0000 AL8550 TC Nothing to report.
0400 AL8556 "
0800 AL8556 BR "
1200 AL8567 TC "
1400 AL8567 E0, Sea 1, clouds clear, Vis. very good Surfaced to replenish oxygen and recharge batteries.
1509 Batteries recharged.
1600 AL8568 Nothing to report.
2000 AL9471 TL "

22.8.41.

0000 AL9472 "
0400 AL9484 "
0800 AL9488 "
1200 AL9731 TC "
1506 Chief Engineer confirmed diesel reserves at 50%. At KF we have plenty of fuel to reach home base. However, I am reluctant to increase diesel engine speed in case we need more fuel in order to chase potential targets.
1600 AL9733 BL Nothing to report.
2000 AL9814 NE7, Sea 5, overcast, heavy rain and fog, Vis. poor Weather has severely worsened. Submerged to 60m.

23.8.41.

0000 AL9810 Nothing to report.
0400 AL9819 TL "
0800 AL9819 "
1200 AL9827 NNW7, Sea 5, overcast, heavy rain and fog, Vis. verry poor Surfaced. Batteries recharged.
1300 Batteries recharged.
1330 No change in weather. Therefore submerged to 60m.
1600 AL9852 TC Nothing to report.
2000 AL9853 TL "

24.8.41.

0000 AL9853 "
0400 AL9861 "
0800 AL9860 NNW7, Sea 4, overcast, medium fog, Vis. poor Surfaced. Recharging.
0911 Batteries recharged.
1000 Radio message recieved from BdU: "Patrol grid BE6 until further orders."
New course: 150°. Increased diesels to HF until we reached BE61.
1200 AL9896 BR Radio message recieved from BdU to Grönland Wolfpack via U-101: "0953 Attacked by aircraft. Two depth charges. No damage."
1600 BE2349 Nothing to report.
2000 BE2652 "
2200 BE2686 Submerged to 60m. Electric motors at KF.
2329 Sonar contact, bearing: 211°. Merchant, speed: slow.
2340 Vis. poor Surfaced. Target heading East. Diesels increased to HF. Course: 65°.
Intention: to get ahead of target following assumed heading.

25.8.41.

0000 BE2694 Course: 21°.
0038 Ship spotted on bearing: 325°. Heading: East. Course change: 85° to run ahead.
0043 Estimated target speed: 7 knots.
0100 New course: 54°.
0110 New course: 87°.
0210 Course: 356°. Battle stations!
0230 Ordered periscope depth for submerged attack.
Target: Steamer, speed: 7 knots, range: 1000m. Torpedoes Eto AZ set at minimum depth due to sea conditions, aim-point: foredeck, stack.
0305 Through the periscope it became obvious that there were two x merchants once out of the gloomy murk of the night sky conditions.
Target #1 with a long centre funnel followed by a smaller merchant.
#1 Steam Merchant 4000GRT.
#2 Small Merchant 2000 GRT.
0322 #1 Green 90°. Tube I fired at foredeck, II at stack 15 seconds after. Both hits after 49 seconds run times respectively.
0324 Tube III was fired but missed.
Target started to turn toward periscope. Dived to 50m. Unable to fire at small merchant as it took evasive action.
Followed second target. Unable to use deck gun due to sea conditions.
0330 Periscope depth. Target #1 has sunk.
Intending to follow small merchant and hope for a weather change rather than waste an eel.
Unable to assist survivors of stricken merchant.
0332 Confirmation of torpedo miss. Through the periscope merchant continuing on original heading. Searchlight lit.
Surfaced to keep up with target's speed. Zigzagging.
0348 Able to determine target's course as original: 87° with zigzagging. Will head further East and attack.
Radio message received from BdU: "Confirmed sinking. British Steam Merchant Alderpool. 4313 tons. Cargo: Wheat. Crew: 39. Crew lost: 0."
2200 Well ahead of target's proposed course. Submerged to 60m, electric motors at KF. Lying in wait.

26.8.41.

0000 BE6531 BC Nothing to report.
0400 BE6530 "
0800 BE6538 "
1200 BE6563 Surfaced. Battery recharge.
Message received from BdU to Grönland Wolfpack via U-652: "0044 Hit Minelayer HMS Southern Prince. Damaged but not sunk. AE9185."
1300 Batteries recharged.
1400 W7, Sea 5, partial clouds, Vis. good Nothing to report.
1600 BE6679 "
2000 BE6964 BL S7, Sea 5, partial clouds, Vis. good "
2238 New course: 270°.

27.8.41.

0000 BE6997 TR Nothing to report.
0400 BE6979 "
0800 BE6897 "
1014 Radio report: "1000 Ship BE6544. Course: WSW. Speed: slow."
160km from our location. Abandoned chase of small merchant for this potential target.
1200 BE6876 TL Nothing to report.
1500 Radio message recieved from BdU to Grönland Wolfpack via U-202: "1435 British Steam Trawler Lady Love. 230 tons. Hit with one torpedo. Trawler sank within 15 seconds. AE8439. Crew: 14. Crew lost: 14."
1600 BE6764 Nothing to report.
1800 Submerged to 60m for hydrophone check.
Course: 50°.
1900 Very faint contact at 310°.
Course change: 00°.
A definite sound contact ahead. Target heading: 240°?
1908 BE6728 Surfaced. Course: 295°.
Interception marked at grid BE6724. ETA: 2030.
2000 BE6724 BR Nothing to report.
2012 Ship spotted on bearing: 106° on starboard.
Intention: to attack using stern tubes.
Course change: 332°.
2025 Ordered periscope depth.
2030 BE6724 Battle stations. Target: Steamer, speed 7 knots, heading: 242°, stern attack green 90°, range: 800m, minimum depth AZ
2106 Target ID: Steam Merchant approx. 5000 GRT.
2115 Steamer is armed. Stern deck gun.
2119 Tube V fired. Aim-point: centre funnel. After 49 seconds torpedo impact.
2124 Through the persicope I could see a hole in the starboard side beneath the centre stack. Target was still moving. Weather conditions hopefully will clear to use the deck gun therefore ran parallel and got ahead of the steamer.
2130 Surfaced but sea conditions still too rough to use deck gun. Shadowed steamer and reloaded stern tube. Stayed out of trajectory of enemy deck gun.
2145 Target heading: 315°.
2155 Target keeling over to starboard.
Radio message intercepted: "SOS. Westpool. U-Boat attack. Hit in starboard. Sinking. Abandoning ship."
2200 Periscope depth in case of aircraft attack. Observed target to ensure sinking.
2210 Coup de Grâce fired dead ahead at bow AZ. After 45 seconds impact.
2216 Finally steamer slipped beneath the surface.
3 x lifeboats observed. Unable to assist survivors due to the clear sky and the risk of aircraft attack following the distress signal intercepted. Distanced us from lifeboats. Course: 270°.

28.8.41.

0000 BE6716 TR S7, Sea 5, partial clouds, Vis. good Sea conditions too rough to load external torpedo. Lookouts alert for aircraft.
Radio message recieved from BdU: "Confirmed sinking. Westpool. 5724 tons. Cargo: Iron. Crew: 45. Crew lost: 35."
0236 BE6714 Course: 118°. Diesel reserves at 30%. Range at HF: 2700km.
Plotted course for St. Nazaire: 1700km.
1 x fore torpedo, 1 x aft torpedo, 1 x aft external (until sea conditions improve, cannot load).
0400 BE6718 Nothing to report.
0700 BE6758 S6, Sea 4, clouds clear, Vis. good Ordered all engines stop. Started to load external torpedo before sunrise.
0800 W0, Sea 1, clouds clear, Vis. very good External torpedo loaded. Diesels at KF.
1200 BE6791 NNW0, Sea 1, clouds clear, Vis. very good, hazy Course: 56°.
1600 BE6768 Nothing to report.
2000 BE6841 "

29.8.41.

0000 BE6818 TC "
0400 BE6813 "
0800 BE6580 BL "
1200 BE6583 "
1500 W6, Sea 5, overcast, Vis. moderate Weather change.
1600 BE6564 Nothing to report.
2000 BE6562 "

30.8.41.

0000 BE6614 BL "
0400 BE6612 "
0800 [Save corruption. The following is only conjecture following a corrupt save as nothing could be salvaged:
Travelling at KF U-73 would have reached Saint Nazaire from its last location in 6 days = 5th September in a direct route.
I had planned on patrolling grid BE63 for a few days to use the last three torpedoes. Therefore my patrol will have ended on the same date as Rosenbaum (7th September) as there was still sufficient fuel travelling at KF.
The ship names sunk have been lost through SHCmdr so I have used the names of those ships sunk by Rosenbaum keeping the tonnage approximately the same as within game.
The following radio messages are still added in order to finish this historical patrol.]

3.9.41.

2200 Radio message received from BdU to Grönland Wolfpack via U-567: "AL8563, 2042 Torpedoed and sank British Motor Merchant Fort Richepanse. 3485 tons. Cargo: mail. Crew: 58. Crew lost: 36."

5.9.41.

1247 Radio message received from BdU to Grönland Wolfpack via U-501: "Norwegian Steam Merchant Einvik hit by torpedo and sunk by gunfire. 2000 tons. Crew: 23. Crew lost: 0."

7.9.41.

1200 St. Nazaire Made fast.

Awarded Iron Cross 1st Class.

Comments of the BdU on the KTB of "U-73" (Rosenbaum) from 1 August - 7 September April 1941:

U-73 contributed well within Grönland Wolfpack and Rosenbaum deserved his Iron Cross 1st Class.

Accredited success:

EMPIRE ENDURANCE 8570 GRT sunk
WAYNEGATE 4260 GRT sunk
ALDERPOOL 4313 GRT sunk
WESTPOOL 5724 GRT sunk

[ninja turtle]

• During this patrol, Rosenbaum and U-73 was unsuccessful in finding/sinking any targets whereas I was able to sink 4 x Merchants.
• Because of the way SH3 starts on the 1st of the month with a new career, I had an additional 6 days within the patrol. However, with the corrupt save the final few days was conjecture.
• Rosenbaum's patrol was 32 days.
• My patrol 'lasted' 38 days.
• Although I was awarded the Iron Cross 1st Class within this patrol, Rosenbaum actually was awarded his on 25th April 1941.
• My next patrol with Rosenbaum will either be his 6th patrol when he travelled from St. Nazaire through the Gibraltar Straits to La Spezia or one of his patrols from La Spezia.

To be continued...

[sublynx]

Thanks for the report! Too bad about the save.