Your post interested me and I happened to have both books so I looked into it to satisfy my own curiosity. I grew up on Galveston Island in the Gulf of Mexico and Wiggins lived there too though I didn’t know her.

Also note that per Rainer, uboat.net’s original “Ships Attacked” section was based on Rohwer’s book and they subsequently coordinated any changes with him through Thomas Weis (now retired) at the Wuerttembergische Landesbibliothek Bibliothek fuer Zeitgeschichte in Stuttgart so the changes could be included in the next edition of Axis Submarine Successes but it appears there isn’t going to be another edition anytime soon.

Perhaps someone from Uboat.net will also comment.

All 70 of the attacks listed in Torpedoes in the gulf for the Gulf of Mexico are accounted for by uboat.net except for these:

U-84 (Kapitdnleutnant Horst Uphoff)
7/16/42 Freighter (no name), DL 6415 (torpedoed and left burning). Rohwer lists this one as 7/16/43, not 42.

U-508 (Kapitdnleutnant Georg Staats)
8/6/42 Freighter (no name), DM 4336 (damaged).
8/6/42 Freighter (no name), DM 4336 (damaged).

According to U-508’s KTB, the above 2 were simply shots into a convoy from 3500 meters (a very long shot for a U-boat) and U-508 dived before the results could be seen. He heard 2 detonations he assumed were torpedo detonations but they could have been end of run detonations (common at the time) or depth charges not hits on a ship. He could even have hit a whale. At any rate if he did hit a ship or two he had no idea what size it was or its name so he couldn’t claim them. He simply shot into a convoy.

Rohwer’s footnote for these 2 shots is “U-508 heard some heavy detonations after 3 min and 3 min & 20 seconds but these were probably depth charges.” He certainly couldn’t verify the claim of hits much less the claim of damage.

Note that it wasn’t uncommon for escorts to drop a few depth charges, not on identified targets, but just to try to keep attacking U-boats away from the convoy. Also multiple U-boats often attacked the same convoy at the same time so the detonation of their torpedoes and depth charges intended for them had to be taken into account as well.

8/18/42 Tanker (no name), DM 2747 (damage uncertain).
8/18/42 Freighter (no name), DM 2747 (damage uncertain). (Staats missed both ships, but he heard detonations in the convoy.)

According to the KTB for both of the 2 above he fired multiple torpedoes at the ships which were 1000 and 1200 meters away and when he heard (but didn’t see) two detonations after 8 minutes and he assumed the 2 ATOs were hits. The ATOs were set to run at 40 knots and 40 knots for 8 minutes is around 10,000 meters, way past his targets. Additionally, at 40 knots the maximum range of the ATO (G7a) was 7500 meters. Again probably end of run detonations or something other than hits on ships.

The second two couldn’t be claimed because “damage was uncertain” and again he didn’t have a name or size to claim.

That leaves this one:

U-84 (Kapitdnleutnant Horst Uphoff)
7/16/42 Freighter (no name), DL 6415 (torpedoed and left burning). Rohwer lists this one as 7/16/43, not 42.

U-84 was sunk on this patrol and so never returned to base. He radioed his report in so there isn’t any KTB or other paperwork to research. He may or may not have hit something and left it burning but the claim cannot be verified.

None of them were verified post war as far as I can tell and uboat.net didn’t credit any of the 5 to U-84 and U-508. However, for technical reasons they may have required a ship name for their database (just a guess).

That should explain why those 5 were not credited by uboat.net.

Now as to Wiggins claims. She claims these ships were attacked or sunk and technically in a pinch you could say the 5 ships above were “attacked” even if the torpedoes missed but that is really stretching the point in the above cases since there is no proof they were even hit and in some cases the individual targets weren’t even identified before the shots. You could legitimately say the whole convoy was attacked and perhaps some ships were hit. But if someone shoots at you then you were attacked even if you weren’t hit and that is essentially what is going on with Wiggins.

For what it is worth, Uphoff also had another “no name” on the 21st and Rohwer’s footnote for it is “U-84 heard a pistol detonating: the torpedo was probably a dud.” It also was not credited to U-84. Wiggins didn’t notice it or at least didn’t include it.

Additionally Wiggins lists Aurora and William C. McTarnahan as being sunk but:

The US Coast Guard tug USS Tuckahoe (WYT 89) arrived and sent a rescue party on board with fire hose and extinguishers. Together with the tug Robert W. Wilmot, the Aurora was towed to Algiers, Louisiana, where she was initially declared a total loss, but later repaired.

The footnote in Rohwer for this one reads “U-506 left Aurora sinking after 2 hits but the vessel was later towed into port.”

The badly damaged William C. McTarnahan was towed to the entrance of Southwest Pass by the US Coast Guard tug USS Tuckahoe (WYT 89) and the American tug Baranca. She arrived in Mobile for repairs on 23 June and returned to service as St. James for US War Shipping Administration in 1943. In August 1943 transferred on bareboat charter to the Soviet Union as Donbass, returned one year later and renamed St. James.

The footnote in Rohwer for this one reads “U-506 reported one torpedo hit on the ship and left her sinking after firing several rounds.”

One more thing.

Every torpedo fired by a U-boat had to be accounted for. Each time torpedoes were fired, a Torpedo Firing Report (Schußmeldung) had to be filled out.

These were the documents Rohwer got his information from. They were filled out on the boat and signed by the Torpedo Officer and the Commander who was also normally the torpedo Officer for submerged shots. The IWO was normally the Torpedo Officer for surfaced shots.

This should answer your question. Uboat.net and Wiggins had fundamentally different objectives so the comparison isn’t really valid. Both books are also way out of date and uboat.net is updated continuously.

Regards,

Ken Dunn