U-Boote bunkers in France, Germany and Norway

https://www.youtube.com/watch?v=CFNVQzTgXxg



Including less known palces like Marseille , Brest, Bergen, Farge, Bremen etc..

 

did the water recede in that last bunker? Awesome find Skipper

 

That last sight, the Valentin factory, appears to have been somewhat different to begin with. Unlike the pens in France or Norway, this one was really small covered shipyard, and not a dock for reprovision and repair. A little looking about causes me to think most of the building was probably dry. Here's a plan from a USAF project report that shows the basic layout of the structure:



The Air Force project is an interesting little study in its own right. The present structure is what remains AFTER a lengthy bombing study that used it as a target to test bunker penetration. But I'm getting away from the water: It would seem the hulls were moved about on some kind of assembly line from station to station. Only at station 13 does it appear the boats were finally put in the water. While this may come as a surprise, contemporary photos show that there's still water in it, though the channel leading from the building has been filled. (And apparently built over with a substantial levy.) My guess is that there was no real need for water access anymore, and postwar users (mostly the German military) probably wanted to protect the thing from storm surge and the like, but had no need to fill the modest interior channel.

Also, if you were at all curious about the construction methods, here's a photo from a German website talking about the camps where folks building this site lived (and died.) Sounds like it was a lot of POWs, mostly. That's a heck of a roof they put on the thing. I was trying to figure out the relationship between the arched truss I saw in Wikipedia and the flat roof now present. That about answers the question.

 

Skipper really nice video, more than a few of which I had not seen. The amount of concrete is impressive. That is a lot of concrete and rebar. what we call reinforcing steel rods. Pictures of the pens under construction or bombed by the British show how much. The steel ids not high grade but ,many a ton of it.

SymphonicPoet, really liked seeing plans and sections , am working on a transverse section today, a steel-wood hybrid house. I love se3ctions cut through anything.

Gaines

 

Tempted to start a new thread on this, but since I'm staff I suppose I should show restraint. **dang nabit**

Caught a snippet of a documentary on the Battle of the Atlantic which caused me to ask a question about U Boat pens.

Considering the level of effort involved and the seriousness of the threat effective U-boat bases on the French coast would present the RN, why do I not recall much information on efforts by RAF Bomber Command to disrupt construction before they became operational?

Did they miss them? Did RAF BC consider it a diversion from their primary target of German industry, or did they try and found it too difficult? If so why try to bomb them after they were completed?

 

Belasar, all good questions. It would appear that during construction would have been a good time. Was the RAF ready that early ? It took Grand Slams later to penetrate but it would appear 1000 pounders would have disrupted it while being built.

Odd but I cannot find a edit button to correct my many typos. . I promise I am not functionally illiterate as it would seem. I have deteriorating eyesight and the small font gray scale type is hard to see until after I post. I will try and play with the fonts and intensity as it is embarrassing to see what one writes !!. The red underlining is also difficult to spot My apologies.

Gaines

 

Edit tab is at the bottom of your post to left of multiquote.

 

Strange, it did not come up on that post. I am aware where it is and use it often but it was blank.....or else my sight is worst than I suspect
Dave 55 told me to hold down control and tap the plus button to increase font size........I can see !!!!!!!!!!! Perfect size, it works , thanks Dave, you cannot imagine how good this is ! And Belasar, the edit tab has reappeared ! I swear it was not there. but that seems impossible.

Gaines

 

The Campbletown raid is known to me., the point of which was more to deny the port to major German surface vessels rather than U boats. It simply seems that raids during construction would be worth the effort. we hear about the Tallboy's but little before.

 

I was just reading The Bombers and the Bombed...it goes into readiness of Bomber Command ..GT brings up a great point on if Bomber Command was ready that early......I say definitely not...I thought BCommand's aim was very poor?
most of St Nazaire pens finished mid 1942? Lancaster operational 1942--that's operational.....still, after initial combat flights, and before Lancaster, that doesn't mean Bomber Command, crews, aircraft, tactics, bombs, navigation,etc were all working to greatest efficiency....and they weren't..
Lorient and Brest pens started 1941....many targets and priorities for B Command....not enough bombers...?
I saw a documentary on those pens and the engineering was phenomenal....some type of 'double-roof', etc.......
as we see in many bombing raids, it takes successive strikes to really put manufacturing/building out of business for a long time.....could they have disrupted building? not for a significant amount of time--IMO
unless they are willing to take catastrophic losses....?
and if Bomber Command made a greater effort to disrupt building, wouldn't the Germans have increased defenses--if they thought the pens were valuable--which they were
I'm sure we have many experts with more information on Bomber Command, etc....would like to know about other priorities, number of aircraft available and German defenses, especially
great topic....we have these massive 'Nazi' structures, almost impregnable and the Brits want to destroy them....the aura of the unterseeboots, etc......great WW2 history

my edit button was not working well either

 

doesn't Lrusso mean it was very difficult to destroy or even hit the docks by airpower? ..that's why they hit it with a naval/ground raid?
it would've taken many raids to even disrupt construction?
they still built the V2s after Operation Hydra--which killed Dr Thiel and Chief engineer Walther...but that was August 1943 when B Command was much bigger and better....with more and bigger bombs and bombers...?..and ''rocket scientists'' were much rarer than concrete construction engineers....the Germans just adapted by moving production, deceptive procedures, camouflage, etc

V-2 one of my favorite reads of all time

 

We might look at it another way - one uses airpower to attack something if one can't get to it on the ground. In St. Nazaire, the explosive power of a Grand Slam bomb, about 9000lb, was placed exactly where it was needed. The raid also enabled demolition parties to precisely attack critical targets like pump houses. The impellor pumps which filled or emptied the docks used large metal castings which would take a year or more to replace; even if Campeltown had failed to explode, the dock and much of the harbor would have been disabled. A few pounds of plastic exposive in the right places could do more than hundreds of tons dropped from aircraft.

Disrupting construction would have required repeated raids, every time the Germans cleared away the mess and got back to work. On the other hand, disrupting a construction site would not require massive bombs or pinpoint accuracy. It might make more sense than letting the Germans finish the pens and then trying to knock them out.

 

great point on few pounds in right place.....but even when the 8th AF got involved, they still weren't disrupting/destroying much, ..no? even then , the pens were done by 1942, yes? doesn't seem like they could've disrupted it much?--without, like I said, catastrophic losses

 

Belazar's question is a good one...they did bomb the docks of Bremen....appears they were trying to directly target the Uboots, facilities, etc first [ obviously ].......this is one of the reasons they constructed the pens, correct? ...buidling of pens had a high priority

''RAF started raids on St Nazaire early in the war''

left pic>building of pens? from http://www.battlefieldsww2.com/Bordeaux_u-boat_bunker.html

diagram > from http://historyarticles.com/gray-wolves-den/ read how sub pens compare to Hoover Dam ... '''Completion of the U-boat pens became the top priority''' far right pic >actual top as seen in diagram

 

... imagine for one moment how many French civilians would have been killed in such raids . We (the Allies) already come in for much criticism in France as we " killed more French civilians than the Germans ever did " just by raiding rail junctions, V1 launch sites etc etc - I've just read this statement in a work by French author Yannick Delefosse. Very sad commentary on the sacrifices of our valiant crews. Given the lack of accuracy already mentioned ( the Butt report was 1942) I'm sure if such raids were ever considered they were rejected for this reason..

 

I agree. Using tallboys would have been dreadful even though Delefosse's statement regarding crtitscism about general bombings reflects nothing but his own opinion. However critiscism has never come from bombing V1 sites, but by the massive destruction of entire cities , sometimes strategic (Caen, La Havre, Lorient etc.. sometimes debatable (Saint Lo etc....) sometimes mistakes (Dunkerque etc..) or even total useless blunders like Royan in 1945. Even when considering the colateral damages, they are in general widely accepted by the large majority of the population. I currently live in France and have organised many commemorations in central France and eveytime they were successes with wonderful grateful people from many countries falling in each others arms and inviting each other in their respective homes. I have never ever heard anyone say something negative, with the exception of some writers or politicians in need of fame, but they go unheeded anyway.

Just like as in Belgium and in Holland, the general opinion is "no hard feelings".

A few commemorations.

Recent ributes to :

Australians : http://www.sudouest.fr/2014/01/07/commemoration-des-aviateurs-australiens-morts-pour-la-france-en-1945-1422220-1579.php

Americans http://www.ouest-france.fr/bretagne/bannalec-29380/la-famille-des-aviateurs-la-commemoration-du-black-swan-3954775

British and Canadians : http://www.lejsl.com/bresse/2013/10/29/commemoration-du-monde-pour-les-huit-aviateurs

Free French : https://www.nice.fr/fr/l-agenda/commemoration-du-regiment-normandie-niemen-1945-2015?type=events

 

During the Pact with the Soviet Union, the Germans even had a base in the Arctic Northern USSR, "near" Murmansk; still used as a base for submarines today:

https://www.google.com/maps/@69.4444789,32.410622,7687m/data=!3m1!1e3

IIRC the Germans declined to extend the lease sometime around the summer / autumn of 1940...

 

thanks Skipper - Delefosse writes specifically about the history of the FZG 76 and the Allied counter measures