Questions on U Boats 1942-1943
 

Working on the SubRon 50 (US Boats operating out of Roseneath 1942-43)for TMO. This requires some knowledge of U boat operations which I am catching up on. Anyways, few questions...

1. Time period October 1942- July 1943, when U Boats left/arrived at French Biscay ports, I know they were under increasing threat. Did they depart/arrive on surface at night only by this point? OR given radar, leigh light, etc were they safer on surface in day time or submerged in the bay?

2.When did the U Flak escorts begin/end? (if they ended)


3. What was the normal cruising speed of a Type 7, Type 9? 9-10 kts?


4. Any other useful information, links, etc, feel free to share.

Hi Bubblehead ive done some diging on the internet and found this hope it helps some


https://www.history.navy.mil/researc...elligence.html


when i play the GWX Steel Sharks Campaign than run the gauntlet running on the surface in the bay of biscay i would dive to periscope depth as soon as i had enough depth under my keel.


U flak info below

https://uboat.net/types/u-flak.htm

normal crusing speed of a type VIIB,C-IXB,C would be 7knots that was deemed the most economical for fuel consumption and distance traveled

Thanks:Kaleun_Salute:

Hi, rechecked my copy of Blair's "Hitler's U-Boat war".

1. seems to have depended on the Skipper. By this time, the bay of Biscay was a very dangerous place with high Allied air coverage. Since Coastal Command ACs were equipped with radar and Leigh lights, surfaced U-Boats were never safe. At night, the sound of ACs was drowned out by the U-Boast diesel. U-Boats preferred travelling on the surface during the day because it was easier to spot ACs from a longer range. Seems that they would have generally traveled on the surface at higher speeds to get through the Bay faster;

2. U-Flak, it was from about june to october 43. The U-Flak escort concept was given up quickly because it just lead to increased U-Boat losses;

3. normal speed. Again depends, best fuel economy speed was using one engine only, 6-7 knots, but that was generally only used when they wanted to stretch range to the limit, for example patrols by VIIs to the U.S. East Coast when they did not have access to U-Tankers. Normally for mid-Atlantic patrols, they would follow orders from U-Boat Control which would often switch them to new patrol zones. Normal cruising speed in the mid-Atlantic was probably more in the 10-12 knots range.

Thanks Bilgerat, big help. Guess U flak will make limited appearances as SubRon 50 boats transferred to PTO in July 1943.

Many, 6-7 knots lol, slow going.

Blackswan'40s extremely detailed:yeah: site on what is the "wizard war" a radar/counterradar stuggle where German Uboats were preoccupied with their radar detection devices: metox etc. actually giving away the uboats' position; caused Uboats to remain submerged at night transiting Biscay and surface in daylight to charge batteries and chance being able to visually spot the inbound radar aircraft. The advent of the schnorkel, while not entirely proof against airborne radar with an extended schnorkel, was the best defense overall. Ultimately, by 1944 and during the invasion, only Uboats so equipped were sent out from the French ports. :Kaleun_Salute:

According to H.Werner extremely detailed testimony, they sent out even those without snorkel (at this time his own U-Boat didn’t have snorkel)… a following each other by night on surface, with the order to fight incoming planes … they didn’t made it very far and many were very badly damaged.
What’s incredible is they had the suicide order to ram ennemy ships after being out of torp!
H.Werner made it back once more, very luckily.

Back to Bay of Biscay offensive, it looks to me like the preferred method was for U-Boats to travel at high speed day/night.

In OP ENCLOSE II (april 5-13, 1943) majority of U-Boats were detected at night:

i.e. 25 crossed the area, 11 (44%) were detected, 4 (16%) were attacked and 2 (8%) sunk/damaged.

and even with massive Allied Air coverage, majority of U-Boats went undetected.

OP DERANGE

https://uboat.net/history/fight_back_order.htm

note the stats, 81 U-Boats crossed the area from 13 to 31 april 43, 36 were detected (44%) , 22 were attacked (27%) and 3 were heavily damaged/sunk (4%), so traveling at high speed on the surface and clearing the area as quickly as possible was still the safest course of action.

Don't know if it was mentioned or not but there was also the so called 'Piening Route' - https://uboat.net/maps/piening-route...orial%20waters).

I was not aware of this but makes sense. Thank you for sharing.

Thanks for all the responses. :Kaleun_Salute:

What are appropriate dates for U boats to get surface search radar . FuMO 21 FuMO 23? My understanding is U boats did not have air search radar for most of the war? One reason aircraft were such a threat to U Boats vs subs in pacific is U boats lacked air search radar for most of the war, vs US had air search radar from the start.

http://www.navweaps.com/Weapons/WNGER_Radar.php As with my reference to the "wizard war" (above posts) https://encrypted-tbn0.gstatic.com/s...89tKA&usqp=CAc http://www.uboataces.com/radar.shtml

How many nautical miles were U boats in a patrol lined spaced apart? . 15-20 ?