Hunt and Kill

by Theodore P. Savas

  Pursuit

  The accurate position estimates from Tenth Fleet had astonished Captain Gallery during USS Guadalcanal’s first two war cruises. Since he was not, of course, cleared for Ultra intelligence, Gallery had no idea how Knowles made his uncanny predictions. Gallery chose to regard Knowles as a “soothsayer” and based his operations on the estimates coming from Knowles and his staff.156 Gallery traveled to Washington before departing on the third cruise. Stopping by the offices of COMINCH, he visited Smith-Hutton, a onetime shipmate and fellow turret officer on the battleship USS Idaho (BB-42), who now occupied the post of Assistant for Combat Intelligence (F-20). Gallery told Smith-Hutton of his intention to capture a German submarine on his next cruise. In addition to promising Gallery reports on submarine activity (on which Gallery had come to rely), Smith-Hutton took him to the head of ONI’s Technical Section, who gave him interior plans of two types of U-boats known to be operating in the Atlantic.157

  Gallery’s Task Group 22.3, consisting of Guadalcanal (CVE-60) and Escort Division Four, the destroyer escorts Chatelain (DE-149), Flaherty (DE-135), Jenks (DE-665), Pillsbury (DE-133), and Pope (DE-134), departed Hampton Roads on May 13, 1944. The task group sailed to York Spit Channel, where Guadalcanal calibrated its DAQ HF/DF gear.158 A burst boiler tube forced the carrier to return to port the next day, but the damage was promptly repaired and the task group set out again on May 15 for what would become one of the U.S. Navy’s most celebrated operations.159

  Daily Operations

  Task Group 22.3 proceeded to its operating area south of the Cape Verde Islands, flying daytime antisubmarine searches and qualifying pilots in night operations along the way.160 Air searches turned up nothing promising, and the only sonar contacts the destroyers reported were evaluated as fish or seaweed.161 A torpedo plane reported a radar contact 10 miles from the task group shortly before midnight on May 27, and a HF/DF bearing was obtained by Pope’s DAQ an hour later, but the contact was lost.162

  Closing in on U-505

  As Gallery’s Task Force steamed through Atlantic waters, Knowles and his staff continued tracking U-505, as well as a dozen or so other submarines. F-21 continued predicting U-505’s position more accurately than BdU, placing it 230 miles southeast of its actual position on May 22, while the square in which BdU placed the submarine was no closer than 377 miles east-southeast of its true location. Knowles continued to include three homebound submarines near Cape Palmas in his daily broadcasts.163 The May 23 dispatch specifically included U-505’s estimated position, 4-30N 12-30W, for the first time. The message included no hull numbers (the daily broadcast was classified Secret, but estimates with hull numbers were Top Secret Ultra), but the position corresponds to that listed for U-505 on that day.164 U-505’s logged position at 10:00 a.m. was 7-33N 14-51W, 231 nautical miles to the northwest.165

  Neither Knowles nor anyone on his staff showed any particular excitement over U-505, as demonstrated by the F-211 summary of May 24, 1944: “Cape Verde Islands…Three U/Boats, now homebound after fruitless patrols in the Gulf of Guinea, are expected to pass between the Cape Verde Islands and Dakar shortly.”166 U-505 was just another enemy submarine to be located and, if possible, exterminated.

  Broadcasts mentioned U-505 in general terms until May 28, when Knowles reported, “One homebound and one moving SE within 200 miles of 10-00[N] 18-00[W].”167 Knowles actually estimated U-505’s position to be 10-45N 19-00W, 74 miles from the center of the circle, while the KTB records the submarine’s position as 15-03N 19-39W, or 318 miles from the center.168

  Messages from May 29 through June 1 include word of a submarine heading north along 19-30W, starting at 12-30N 19-30W on May 29, figures corresponding to Knowles’ estimates of U-505’s position.169 The messages until June 5 show a submarine continuing north along 19-30W, advancing two degrees (120 nautical miles) per day. F-21’s Ultra estimate for June 1, the last day for which a location list has been found, placed Lange’s U-505 175 miles south-southwest of the position in the KTB, while BdU’s estimate was 503 miles northwest of the actual position.170 Both sides were now overestimating U-505’s progress home.

  Since TG 22.3 was running low on fuel, Gallery set a course for Casablanca on May 31. It was a simple matter to head north within aircraft range of 19-30W.171 Gallery’s airplanes flew day and night searches over an area 100 miles to either side of U-505’s estimated track. On June 2, Lange despaired over the “continuous night patrols” saturating the airspace, as evidenced by radar emissions detected by his Naxos warning system.172 Although shipborne enemy radar occasionally surprised crews operating Naxos (which was carried aboard most U-boats at this time of the war), the radar detection gear was very sensitive to aircraft radar. As a result, it often provided warnings of airplanes operating far too distant to pose a threat. This was probably true in Lange’s case, for on June 2 the task group’s closest planes were more than 200 miles away. During the next night, a torpedo plane reported disappearing radar contacts east of the carrier at 18-45N 19-10W. The pilot dropped two sonobuoys into the water and reported hearing motor noises. After listening for two hours, the pilot dropped depth charges without observing any results. U-505’s logged position at that moment was 20-03N 18-33W, or 85 miles to the northeast.173

  During the morning of June 3, Commander Earl Trosino, Guadalcanal’s chief engineer, warned Gallery that their fuel level was below safe limits. Gallery decided to risk one more day of operations, confident the task group was closing in on a U-boat. Another frustrating night of operations followed. Guadalcanal and Pope picked up HF/DF bearings at 5:20, an hour before sunrise on Sunday, June 4. Guadalcanal’s DAQ operator picked up a U-boat signal bearing either 024 or 200 degrees at 6:29 a.m., but nothing came of the contacts.174 At about the same time, Trosino advised Gallery, who was Catholic, “You better pray hard at Mass this morning, Cap’n. You used more oil than I figured on last night.”175 Gallery resumed course, seething over his failure to find a submarine and hoping he had enough fuel to reach Casablanca. Less than six hours later Chatelain picked up U-505 on sonar.176

  Intelligence Exploitation of U-505

  Document Exploitation

  The capture of U-505 provided the Allies with a treasure trove of intelligence riches. Gallery obviously appreciated the significance of the items removed from the boat. On June 6, with the Allies landing in Normandy, he apparently believed the captured material assumed even greater importance. That night he sent a Top Secret Operational Priority Message to CINCLANT advising he possessed “material which should be examined by communication experts immediately.” He suggested communications experts and personnel from the Bureau of Ships (BUSHIPS, now the Naval Sea Systems Command, or NAVSEA) fly out to Guadalcanal by seaplane to collect the half-ton of documents and equipment his men had taken from the captured German U-boat, which was now being towed to a safe haven by the Allies.177

  Gallery’s plan was not adopted, and Jenks carried the captured material to Bermuda at top speed. As soon as Jenks arrived, the captured documents were loaded on an airplane and flown to Washington. The Atlantic and Indian Ocean Enigma keys for June arrived at OP-20-G on June 12.178 For the rest of the month OP-20-G was able to read this traffic just as quickly as the Germans. Additionally, possession of these keys freed up 13,000 hours of Navy bombe time in June, allowing OP-20-G to work on Wehrmacht and Luftwaffe keys, an important consideration as the invasion of Europe progressed.179

  Other documents were also of immediate use. OP-20-G copied U-505’s “cipher charts” (Addressbuch) and sent them to F-21 on June 22.180 These charts allowed F-21 to strip the second layer of encipherment from U-boat position reports directly, with no analysis necessary. Possession of the Addressbuch also gave Knowles and his assistants a greater degree of confidence in their position estimates.

  OP-20-G also obtained the Short Signal Cipher that was due to go into effect on July 15. This cipher was used for tactical signals, and experience showed OP-20-G would have required about four months
to reach a point where short signals could be read with no delay.181 The reserve Bigram Tables taken from U-505 were scheduled to take effect on August 1, 1944, which would have introduced a delay of 24 hours to 10 days in decrypting all Enigma traffic until the tables were reconstructed.182 Of less importance, but still valuable, was the Short Weather cipher, which allowed OP-20-G to determine the position of any U-boats sending weather reports.183

  The Office of Naval Intelligence lacked the resources to translate any but the most critical documents with any haste. As late as October 21, 1944, Commander B. F. Roeder of OP-20-GI-A sent a memo to Frog Low explaining his section had only one translator available, that no more translators would arrive until December, and the only assistance he had been able to enlist was that of OP-16-Z, which had agreed to translate three items from Low’s own priority list.184

  OP-20-G became the custodian of U-505 documents. The collection contained approximately 1,200 items, 800 of which were technical documents and navigational charts. The remaining 400 items, U-505’s document library, were categorized as follows:

  Torpedoes: 15%

  Radio Communications (operational and technical): 12%

  Codes and ciphers: 13%

  Manuals for the C.O., orders, etc: 4%

  Ship and A/C recognition: 3%

  Ships logs, receipts, and papers: 10%

  U/B technical documents (including periscopes,

  diesel and electric machinery): 27%

  Navigation: 13%

  Miscellaneous (personal, etc.): 3%.185

  Material Exploitation

  Inspection

  Low arranged a flight from Washington National Airport to Bermuda on June 20. The R5D (a naval version of the Douglas DC-4) carried officers from COMINCH (including Knowles), ONI, the Submarine Design and Sonar Design sections of BUSHIPS, and the Bureau of Ordnance’s (BUORD) Torpedo Design section and Mine Disposal Group. The ONI contingent included three officers from OP-16-Z and one from OP-20-G. These experts made their own examination of U-505, interrogated prisoners, and removed the torpedoes from the submarine. Most members of the party completed their work within a day and returned to Washington on June 21.186

  The Submarine

  Inspection of U-505 revealed a hole in the number 7 ballast tank caused by a 20mm shell. The port bow plane had been torn off in a collision with Pillsbury during the capture, but a copy could be made in Bermuda.187 By August 31, the submarine was ready for surface operations, with an American crew of one ensign, two warrant officers, and 30 enlisted men.188

  A memorandum dated December 11, 1944, describes U-505’s electronic equipment from bow to stern, concentrating on the radio gear and hydrophones.189 The anonymous writer thought well of nearly all of the German electronic equipment, with the exception of the design of the low-frequency direction finder antenna. “This is considered extremely poor practice in the U.S. Navy,” he concluded.190

  The U.S. Navy used “Nemo” (as U-505 was code-named), as a training submarine for the rest of the war, which provided naval operating forces an opportunity to learn the characteristics of the U-boats and antisubmarine experts an opportunity to develop and improve ASW tactics.191

  The Torpedoes

  While any information that could be obtained from U-505’s torpedoes would be valuable, the Bureau of Ordnance was particularly anxious to examine the T-5 acoustic homing torpedo, a significantly more dangerous weapon than earlier models. The T-5 followed a ship’s propeller noise to the target, which defeated the traditional countermeasure of steering a zigzag course when a ship’s lookouts spotted a torpedo in the water. Via COMINCH, the Bureau of Ordnance requested the team in Bermuda to send a T-5 by ship to the Naval Mine Warfare Test Station (NMWTS) at Solomons, Maryland.192 In fact, the Bureau of Ordnance was so anxious to obtain a T-5 that if two were available, the bureau would send an airplane to collect the first one. 193

  Although the torpedo board in U-505 indicated the inspectors would find T-5 acoustic torpedoes in tubes 2, 5, and 6, only two T-5s were located.194 A quick review of prisoner interrogation records revealed the crew of U-505 fired the torpedo in tube 5 shortly before abandoning ship.195

  Although no messages directly confirming air shipment of a T-5 have been located, a message from Low directed CINCLANT to “Send remaining torpedoes from Nemo…via water transportation.”196 Other messages indicate USS Chaffee (DE-230) departed for Solomons on June 29 with a T-5 on board.197 Over the next three weeks Rudderow (DE-224), Sperry (DD-697), and Fessenden (DE-142) departed Bermuda with 12 torpedoes, 11 detonator pistols, U-505’s scuttling charges, and ammunition for the deck guns.198

  The testing of the torpedoes began immediately. By early September, extensive tests of the two acoustic torpedoes recovered from U-505 indicated that the FXR (“Foxer”) Mark IV countermeasure device used by U.S. warships might be ineffective against the T-5.199

  Water-Soluble Ink

  On May 3, 1944, British aircraft located and heavily damaged Heinz-Wilhelm Eck’s U-852 in the Arabian Sea off the east coast of Somalia. Hard aground, the Germans abandoned the boat without effectively destroying its valuable contents. Inside, Allied boarders recovered eight secret communications publications wrapped in a tablecloth. Five were printed in water-soluble ink on special paper. Unable to recover any information from the documents, Bletchley Park forwarded them to American Army chemists in Washington for evaluation. Several of the documents taken from U-505 were printed with the same water-soluble ink. OP-20-G forwarded samples of the ink and paper to the Army, which eventually recovered usable intelligence from the U-852 material.200

  Interrogation and Disposition of the Crew from U-505

  Low’s June 18 memorandum does not specify which of the representatives from OP-16-Z—Lieutenant Commander H. T. Gherardi, Lieutenant T. H. Erek, or Lieutenant H. H. Hart—interrogated the crew of U-505. The handwritten notes taken during the initial (“rough”) interrogations appear to be in the handwriting of at least two individuals.201 Perhaps all three officers interrogated the prisoners in an effort to complete their work before flying back to Washington on June 21.

  Some of U-505’s crewmen limited their answers to name, rank, and serial number, as required by the Geneva Convention. Others, however, more willingly provided additional information. Many told of U-505’s history as well as their own. One man told his interrogator where to find the T-5 acoustic homing torpedoes on board the captured boat.202 Two men provided ONI with the first details of former commander Peter Zschech’s suicide during a patrol in the fall of 1943—news that must have startled the examiners.203 Others offered the welcome news that the crew had abandoned U-505 too quickly to send a distress signal.204 The men from OP-16-Z recorded their impressions of the men for use during subsequent interrogations. These notes are usually variations on a few basic themes:

  “Will answer anything.”

  “Completely OK.”

  “A nice lad.”

  “Completely OK but dumb.”

  “Refuses all answers and is to be treated as a bastard.”205

  “It will be a hard life—have no illusions about that. But with a well-disciplined crew, we’ll have our successes.” Kplt. Axel-Olaf Loewe’s honest observation was spoken during U-505’s commissioning ceremony on August 26, 1941. He knew of what he spoke—it was a hard life indeed.

  Kplt. Axel-Olaf Loewe as he appeared while commanding U-505, wearing the standard denim battledress blouse and distinctive white cap associated with U-boat captains. He was later promoted to Korvettenkapitän and served as a staff officer in Admiral Karl Dönitz’s headquarters. Loewe ended the war in command of a naval antitank unit. The Kiel native of Crew 28 died in December 1984. He was the boat’s most successful captain.

  Ill-fated Peter Zschech, scanning the horizon during a stressful patrol in Carribean waters, and (right) in happier times, probably during the fall of 1942 when he succeeded Axel U Olaf Loewe as commander of U-505. Wearing standard service dress, the youthful Oberleutnan
t zur See’s tunic bears his decorations: the Iron Cross First and Second Class; the Destroyer Badge, and the U-boat Badge. Denied success, Zschech took his own life during a war patrol one year later.

  Stately Oblt.z.S. der Reserve Harald Lange. Before taking over as U-505’s final commander, the 40-year-old prewar merchant marine officer saw action in patrol boats and on U-180. Lange restored morale aboard U-505 and was well liked by his crew, but he could not prevent the boat’s capture after suffering wounds that would cost him his right leg.

  Harald Lange and his officers before leaving Lorient on their first war patrol together in late 1943, from left to right: Leutnant zur See der Reserve Kurt Brey (Second Watch Officer); Stabsobermaschinist Willi Schmidt; Oberleutnant z.S. Paul Meyer (First Watch Officer); Bootsmann Heinz Möller; Oblt.z.S.d.R. Harald Lange (commanding officer); Obersteuermann Alfred Reinig; Marineoberassistenzarzt Dr. Friedrich-Wilhelm Rosenmeyer (Ship’s Surgeon); Obermaschinist Otto Fricke; and Oblt. (Ing) Josef Hauser (Chief Engineer).

  U-505’s senior NCOs, left to right in the asending order of their seniority: Bootsmann Heinz Möller; Obermaschinist Otto Fricke; Stabsobermaschinist Willi Schmidt; and Obersteuermann Alfred Reinig.

  U-505 authors. Machinist Hans-Joachim Decker (above, left) left a memoir of his service with “404 Days! The War Patrol Life of the German U-505.” He moved to America in the 1950s and occasionally led lucky visitors on tours of his former home. Hans Goebeler (above, right) spent duty time in the Control Room. History remembers him as the man who “pulled the plug” on U-505. His book Steel Boats, Iron Hearts is one of the most valuable firsthand U-b0at accounts ever published.