Hello guys,
Jon (Capt Kremin) has kindly sent me the direct quotes from Hans Groebeler's Steel Boats, Iron Hearts. This has proved a VERY big help to try to solve the timeline puzzles.
"By late May of 1943, the modifications and repairs on our boat were almost complete. Gone are the large gangs of shipyard workers in their thick brown welder's suits. Only a few technicians were to be still found aboard finishing some small details. U-505 sported a totally new silhouette. We were especially excited to stand on the spacious Wintergarten, with its deadly looking quad barreled flak gun. Combined with the two twin-barreled 20mm guns on either side of the conning tower, our new boat now boasted a total of eight 20mm guns for anti-aircraft defense. At least now, we thought, we would have a fighting chance against any enemy birds trying to drop an egg on us."
"On July 1, U-505 was moved to a wet dock in the bunkers. With her new and much larger conning tower and fresh coat of dark grey paint, she was unrecognizable as the same boat that had limped into harbor more than six months earlier."
Already quoted page 137 about only loading 37mm ammunition.
After patrol 6 page 145, quote "For the next two weeks, our boat underwent repairs. They also replaced our huge four-barreled anti-aircraft gun with a newly designed single barreled Oerlikon 37mm automatic cannon.
These quotes are very specific and I believe Jon is right that the dates of the Turm IV fitting can be relied upon. I previously thought that the "well wishers" photo showed U 505 departing or returning from patrol. Its a classic Das Boot style departure, with everyone urging them good hunting. However, just because it looks like a departure does not make this certain. Given Hans' infomation it is appears that U 505 never went on patrol with a Turm II and the "well wisher" photo simply shows them on a refresher training or test dive. The crowd might not have known it wasn't a war patrol and so waved to the crew, who naturally waved back.
This timeline is, as always, subject to change if new info comes to light, but where we're at now is for refit 5X to have the following -
1 - Major repairs from Hudson attack
2 - Change from Turm 0 to Turm II
3 - Test run with Turm II (when the "well wishers" photo was taken
4 - Change from Turm II to Turm IV and change to darker grey
I've done more research into the dates when Turm II and Turm IV were fitted and the new timeline (with both Turms being fitted in 5X) does seem to fall nicely into the dates when Turms were changed. By the way, there is very good info on this in U-Boot im Focus 9.
Hopefully we're getting there now...only the 37mm to go. Hans' date for the change from Vierling to 37mm is refit 7X (mid-to-late July). This is the part that concerned me because it doesn't accord with the dates in books. According to Eberhard Rössler in his excellent The U-Boat: The Evolution And Technical History Of German Submarines, the 37mm automatic was ordered on the 15th October 1943. In Robert C Stern’s Type VII U-Boats, the author asserts that that the 37mm automatic “finally began” to be fitted in November 1943, with 18 boats (probably 18 Type VIICs, don't know how many IXs) being fitted by the start of December. If this information is correct then the most likely fitting date for the 37mm on U 505 would be refit 12X (08/11/43 to 20/12/43).
However, I am beginning to agree with Jon that Hans might be right about the mid-July fitting date. Firstly there would probably have been experiments made before the 15th October order and there is no reason why U 505 could not have trialed the 37mm. Secondly, there is a photo of U 707 on 12th October with the 37mm. Okay, thats only three days before the order but the precedent is there for boats going on patrol before the 37mm was actually ordered. I think I'll let you guys decide when it was fitted, I think a plausible argument could be made for 7X.
The Balcongerat should be added to the timeline. Assuming U 505 wasn't the IXC which trialed it (don't think so), then perhaps it was fitted in 1944? Perhaps during refit 14X?
Cheers,
Dougie
PS - A big thank you to Jon for the quotes and other info.