In 1942 the U-511 under the command of Friedrich Steinhoff, was involved in tests of an unusual nature for a submarine of that day. The plan was to fire a rocket from underwater with the intention of targeting allied convoys. Launching rails were added to the U-511 and tests were made in the Baltic Sea with mostly disappointing results. However at least one rocket was successfully launched from below the waves but this was not effective enough to warrant further testing. The rockets used had no guidance system and it would seem unlikely that they would ever hit a ship with one.

In 1943 an idea was put forth to attack the USA with the infamous V-2 rocket but, the V-2, one of Hitler's terror weapons, lacked the range to reach US soil on it's own. The only way to accomplish this was to transport the V-2 close enough to the east coast and launch it at sea. It may have made sense if they had used a large merchant ship for this task, surely they could have converted the ship into a floating launch pad for one or more rockets but, the German's looked once again at the U-boat force for the task.

The idea was to seal the V-2 in a watertight container and tow it behind a submerged U-boat to the USA. Upon reaching the designated launch zone the container would be allowed to surface and then water ballast would be taken into one end so the container would be vertical with the water allowing the rocket to be fired. The obvious drawbacks of a rough sea or the possibility of being interrupted by hostile warships while preparing the rocket for launch made this proposal slightly more difficult than just overcoming the logistics of getting there. At least one successful test of towing a 90 ton container behind a U-boat was made in the Baltic, proving that a U-boat could do the job, however the plan. like many of the desperate plans the German's had at this stage of the war, came to naught. It appears that after this test no further attempts were made to complete the plan.

On August 20, 1944 the U-1229 was approaching the US but was located by the USS Bogue CVE-9 and attacked. The aircraft depth charged the boat until she sank leaving forty one survivors. One of them was Oskar Mantel, a German spy who was to have been landed in Maine. He was turned over to the FBI who also had other captured German spies in custody. From these men they learned about the V-2 program and became very concerned about the possibility of a rocket attack.

The response to the threat was Operation Teardrop. Increased shore defenses and two carrier task forces positioned to intercept the U-boats. In mid March the US received notice that a force of seven U-boats named Gruppe Seewolf, had departed from Norway en route to the USA. It was also learned that Friedrich Steinhoff was in command of one of the boats, the U-873, this raised a red flag and the carrier groups were alerted to be on the lookout.

There seems to be some confusion as to which U-boats were involved in Gruppe Seewolf, with some sources sighting U-808 as one of them. However, U-808 was never a commissioned boat and never took part in any operation. The boats involved I believe were; U-518, U-546, U-880, U-853, U-873, U-880 and U-1235. It must be noted though that while these boats were all engaged in or en route to operations off the US east coast, these boats did not leave together, they departed on different dates (Feb. 23-Mar. 30) and from different ports, one leaving from Kiel the rest from Norway.

Whether these seven boats were Gruppe Seewolf or not the alert was out. The first boat located was the U-1235. On April 15, 1945 the USS Stanton DE-247, of the northern group, got a target on her radar. While there was a dense fog, the Stanton moved to within 1000 yards and then turned on her spotlight. Through the fog a shape of a U-boat could be seen. U-1235 had been running on the surface, due to the rough seas she was not able to use her schnorkel. Soon the Stanton was joined by the USS Frost DE-144 and they made a coordinated attack using their Hedgehog ASW weapons. Powerful explosions were felt and soon large amounts of diesel fuel was seen on the surface. The U-1235 had ended her one and only war patrol and took with her all 57 of her crew.

Less than an hour later Frost picked up a target on her radar and Frost and Stanton began another attack. Using the same weapons, the same results were accomplished. U-880, also on her first patrol was sent to the bottom with her entire 49 man crew. Since no survivors were picked up from either boat, the question of if they were en route to make a rocket attack on the USA was not answered. Since no intelligence was gained, the high state of alert was maintained.

The next contact was not made until Apr. 22 when the USS Carter DE-112 picked up a sonar contact. The USS Neil A. Scott DE-769 joined in the attack sinking the U-boat, once again, with no survivors among the 56 man crew. The explosions reported when the U-boats were sunk gave pause to the men on board the destroyers. They seemed "more powerful" than just torpedoes exploding and many wondered if they had indeed been carrying something along with their usual deadly cargo.

On April 24, 1945 they had a chance for an answer. The U-546, commanded by Paul Just, sighted one of the carrier groups and planned to sink the carrier Bogue. Even though the Bogue was well protected by escorting destroyers, Just made a run for her, but before he could get in range the USS Frederick C. Davis DE-136 sighted the periscope and turned toward the target. Just, observed the Davis making the turn and ordered an acoustic torpedo loosed on the destroyer. The torpedo found the mark and the Davis broke in two and sank within five minutes taking over 100 of her crew with her.

But now the presence of the U-546 was known to the remainder of the US ships and an attack was made. In a chase which lasted over ten hours, the destroyers used depth charges and hedgehogs to pound the U-boat until finally she surfaced. As soon as she broke the surface almost the entire destroyer force opened fire on her sending her to the bottom. While the U-546 had made two previous patrols she had sunk only one ship, the USS Frederick C. Davis. And while dozens of US sailors had just been killed by this U-boat, the survivors were picked up without hesitation. Among the survivors was Just, finally the US had someone they could question about the operation.

They were taken aboard the Bogue and questioned and according to accounts, gave no information about the mission. After putting them ashore in Argentia, Newfoundland, Just and six others were taken to solitary confinement and subjected to "intense" interrogations.

To what degree the interrogations went can only be guessed at but, after one "session" was witnessed by the CO of the USS Varian DE-798, they were transferred to Fort Hunt but, the "sessions" continued there. Just however had no knowledge of any rocket attacks and the US Navy knew it, or at least they had evidence that Just's boat had only the normal complement of torpedoes and nothing else. They knew this information because the war diary of the U-546 was picked up by the USS Varian and inspected. It could be noted that the diary could have conveniently left out any reference to rockets and that the FBI interrogators would surely been aware of that.

Of the remaining three boats one, U-853 was sunk on May 6 with her entire crew but not before she had sunk the USS Eagle PE-56 and the cargo ship Black Point. Eagle lost 49 of her crew and Black Point lost 12.

U-805 was surrendered at Portsmouth, NH on May 14 and was searched by the Navy and of course no V-2 rockets were found. This left  only the U-873 under the command of Friedrich Steinhoff still on the loose.

When Steinhoff surrendered his boat on May 16 he was taken into custody not by the Navy but by the FBI. Because he had been involved in rocket tests in 1942 he was a valuable asset. They were taken to the Charles St. Jail in Boston where treatment was brutal. I must say at this time that I don't know if the FBI was at fault or if the other prisoners in the jail were the culprits but, on May 19 Steinhoff could take no more and he cut his wrists open and bleed to death despite efforts by the doctor of the U-873. His body was buried at the cemetery at Ft. Devens, Mass.

© 2006 Michael W. Pocock
MaritimeQuest.com

A Type VII U-boat under attack.