Military history


While the RAF and Luftwaffe fought the air Battle of Britain in August 1940, thirteen oceangoing boats sailed from Germany to continue the U-boat campaign in the Atlantic. These included two new boats, the VIIB U-100, commanded by Joachim Schepke, age twenty-eight, who had sunk eleven ships for 18,000 tons while commanding the ducks U-3 and U-19, and the IXB U-124, commanded by Georg-Wilhelm Schulz and manned by other survivors of his U-64, sunk in the fjord at Narvik. All thirteen boats were to patrol the northerly hunting grounds near Rockall Bank, then put into Lorient. One IXB, U-65 (von Stockhausen), was to first land two Abwehr agents in Ireland.

Since the British were transfixed by the air battle or preparing for the supposed German invasion, Dönitz anticipated another low-risk slaughter like that of June. In response to his petition, Hitler had authorized unrestricted submarine warfare to 20 degrees west longitude as of August 17.*Moreover, B-dienst was operating at peak efficiency, providing Dönitz a wealth of specific information on convoy routing and escort rendezvous, which offered the possibility of a resumption of pack attacks.

But a number of things went wrong in the initial foray of these nine boats. Sailing from Wilhelmshaven on August 1, the big, cranky U-25, commanded by Heinz Beduhn, blundered into a minefield and was lost with all hands. British air patrols caught and bombed Viktor Oehrn in U-37 and Dietrich Knorr in U-51, inflicting so much damage that both boats had to abort to Lorient. The hit on U-51 was credited to a Sunderland of Coastal Command Squadron 210, piloted by Ernest Reginald Baker. As U-51 was approaching Lorient in the early hours of August 20, the British minelaying submarine Cachalot, commanded by David Luce, torpedoed and sank her with the loss of all hands. Von Stockhausen in U-65 was compelled to abort the landing of the two Abwehr agents in Ireland owing to the death of the senior agent. Thereafter, U-65 incurred a mechanical breakdown and limped into Brest, seeking repairs.

These misadventures left only five boats from Germany to patrol the convoy hunting grounds near Rockall Bank in early August. For the first ten days, all were beset by unseasonably stormy weather (as were the aircraft in the Battle of Britain). Nonetheless, Heinrich Liebe in U-38 sank two ships for 12,500 tons, including the 7,500-ton Egyptian liner Mohammed Ali-Kebir, carrying 860 British troops to Gibraltar. About 320 troops perished, but about 540 were rescued by a British destroyer. These two sinkings raised Liebe’s confirmed bag to eighteen ships for 87,000 tons. Counting two overclaims for 13,000 tons, he qualified for a Ritterkreuz, which was awarded while he was still on patrol.

With clearing weather, the five boats near Rockall Bank had somewhat better luck.

• Engelbert Endrass in U-46 severely damaged two ships, a Dutch and a Greek.

• Hans Rösing in U-48 sank two ships, a Swede and a Belgian, for 9,900 tons.

• Joachim Schepke in the new VIIB U-100 sank a 5,000-ton British freighter.

• Fritz Frauenheim in U-100 sank a 4,500-ton British freighter.

These were better returns, but until August 23, the results of the nine boats sailing from Germany were considered disappointing: merely eight ships sunk and two damaged.*

At this time B-dienst went “blind” or “deaf.” After one full year of war, the British realized that Royal Navy codes were compromised and on August 20 they changed all the naval encoding systems. The OKM diarist commented: “This is the most serious blow to our radio intelligence since the outbreak of the war…. It is remarkable that it had not been done before now….” B-dienst was hopeful that the new British codes could be broken “in six weeks or so,” the diarist noted. But that hope was not to be realized.

The loss of British naval codes may not have been the most serious blow for the U-boat force. During the first year of operations Dönitz had laid numerous submarine traps for British naval formations, important troop convoys, and merchant-ship convoys, but owing to inclement weather, errors in navigation by the U-boats or the British, wrong or late information from B-dienst, and other factors, almost none of the traps had paid off and a great deal of U-boat patrol time had been wasted. The sailing cycles on most convoy routes had been well established; lax exhaust-smoke control and communications security in convoys was expected to continue. The only really serious setback was the loss of intelligence on positions and operations of British submarines conducting ASW.

In spite of the lost intelligence, the U-boats performed extremely well in the last week of August.

Having repaired his battle damage in Lorient, Viktor Oehrn in U-37 returned to the hunting grounds to sink a record seven confirmed ships for 24,400 tons in merely four days, including the 1,000-ton British sloop Penzance, misidentified and credited as a “destroyer.” Hit by air and surface escorts, Oehrn was compelled to abort to Lorient for the second time.

• Joachim Schepke in U-100 sank five more ships for 21,000 tons, and damaged a sixth.

• Endrass in U-46 sank four ships for 29,800 tons, including the 15,000-ton auxiliary cruiser Dunvegan Castle.

• Rösing in U-48 sank three more ships for 19,200 tons, including two British tankers, the 6,800-ton Athelcrest and 6,700-ton La Brea.

• Hans Jenisch in the Type VII U-32, who sailed from Germany August 15, sank three ships for 13,000 tons and damaged the British light cruiser Fiji.

• Fritz Frauenheim in U-101 sank or fatally damaged two more ships (a Greek and a Finn) for 7,700 tons.

• Günter Kuhnke, in the Type VII U-28, sank two ships for 5,500 tons.

Perhaps influenced by Göring’s generous award of the Ritterkreuz to Luftwaffe pilots for unverified and exaggerated kills in the Battle of Britain, and/or for internal and external propaganda purposes, Dönitz became less stringent in assessing U-boat claims. Berlin continued to trumpet exaggerated U-boat kills: Hans Jenisch in U-32, who sank 13,000 confirmed tons, was credited 40,000 tons; Joachim Schepke in U-100, who sank 25,800 tons, was given 43,000 tons. Dönitz more freely awarded Ritterkreuzes. Three other favored skippers who had made but two Atlantic patrols benefited from the relaxation: Engelbert Endrass in U-46 (credit 105,000 tons, actual 65,347 tons); Hans Rösing in U-48 (credit 88,600 tons, actual 60,702 tons)*; and Fritz Frauenheim in U-101. Frauenheim had sunk but 54,300 confirmed tons on U-101, but when his earlier sinkings on the duck U-21, including the minefield that savaged the 11,500-ton heavy cruiser Belfast, were added, his total was 72,300 tons.

Among the last boats to sail from Germany in August was Georg-Wilhelm Schulz’s new IXB U-124. In honor of the German Alpine troops who had saved them when their former boat, U-64, had been sunk in Narvik, the U-124 crewmen had adopted the Alpine forces insignia, the mountain flower edelweiss, and had emblazoned an enlarged version of it on the conning tower.

On the night of August 25 Schulz found convoy Halifax 65A close to the north end of the Hebrides in heavily patrolled, shallow waters and attacked on the surface. As he was threading in through the escorts, he impulsively fired his two stern tubes at a “destroyer.” Both missed and the unsuspecting “destroyer” cruised on. When Schulz had brought U-124 to firing position, he chose four freighters and fired one torpedo at each, spacing the torpedoes one minute apart. All four torpedoes were seen to hit and explode. The salvo appeared to be the most astonishing of the war: four ships of 30,000 tons sunk by four torpedoes in five minutes! But the claim was incorrect. Only two of the four ships sank. A third, the 4,000-ton Stakesby, was damaged but survived. The fourth torpedo must have missed.

There was no time to celebrate the supposed victory. One of the destroyers caught U-124 in its searchlight and pounced, forcing Schulz to crash dive and go deep. At 295 feet the boat hit an outcrop of rock and jarred to a stop. That terrifying moment was followed by another: a rain of close depth charges. Schulz got the boat off the rock, eased deeper, and bottomed at 328 feet. The destroyer made one more desultory depth-charge run, but then gave up the hunt.

Later, after hauling well out to sea, Schulz sent a diver down to inspect the bow for damage incurred when the boat hit the rock. It proved to be serious: Three of the four bow caps had been damaged; only one was fully functional. Upon learning this, Dönitz ordered Schulz to leave the hunting grounds and go west to latitude 20 degrees, where he was to broadcast weather reports, which were urgently needed by the Luftwaffe. While doing so, one of the men carelessly half-flooded the stern torpedo room, causing a temporary emergency that evoked chilling memories of Narvik.

The thirteenth and last boat to sail from Germany in August was Prien’s U-47, which put out from Kiel August 27. By then six of the surviving ten Atlantic boats that preceded him in August were in or headed to Lorient for refit, replenishment, rest, and rewards. The other four remained in the hunting grounds: Kuhnke in U-28, von Stockhausen in U-65, who had resailed from Brest, Frauenheim in U-101, and Schulz in U-124 (with three damaged bow caps) on weather-reporting station.

Prien entered the hunting grounds on September 2, and that afternoon his periscope watch detected an unusual cloud of black smoke on the horizon. It turned out to be the 7,500-ton Belgian freighter Ville de Mons, inbound from New York with no escort and badly in need of a boiler cleaning. Prien hit her with one torpedo and saw the crew abandon in three lifeboats. When the ship showed no signs of sinking, Prien surfaced to polish her off with his deck gun, but changed his mind and put her under with another torpedo. One crewman died of exposure, but the others were rescued.

The codebreakers at B-dienst provided Dönitz with further information on North Atlantic convoys, deduced from lapses in Allied radio security and other sources. The information included the important news that to reduce the shipping congestion in Halifax, Nova Scotia, and to sail more merchant ships in the favorable late summer and early fall weather, the British on August 15 had initiated a second convoy system on the North Atlantic run. These new convoys departed from the more northerly Canadian port of Sydney, on Cape Breton Island, a part of Nova Scotia, which, owing to ice, closed in winter. They were designated SC to indicate the geographic location (Sydney-Cape Breton, much as HX indicated Halifax), but because they traveled at only 7½ to 9 knots, the SC became corrupted to mean “Slow Convoy,” as opposed to the faster HXs.*

On September 2, B-dienst alerted Dönitz to inbound Slow Convoy 2, composed of fifty-three ships. Dönitz directed Prien to intercept the convoy at a designated location near 20 degrees west on September 6, before it picked up its escort. Dönitz planned that three other boats would join Prien for the attack: U-65 (von Stockhausen), U-101 (Frauenheim), which had only six torpedoes left, and possibly U-124 (Schulz), despite her three damaged bow caps. The other boat, the Type VII U-28 (Kuhnke), could not operate so far west because of fuel limitations. However, an appeal to Berlin to release U-124 from weather reporting was rejected, leaving only three boats (U-47, U-65, U-101) to attack the convoy.

En route to the designated area on the evening of September 3, Prien in U-47 unexpectedly ran across another convoy, Outbound 207. Husbanding his torpedoes, he picked out two targets and carried out a night surface attack. He sank the big 9,000-ton British freighter Titan and claimed damage to another of 4,000 tons, but the latter could not be identified in postwar records.

By the morning of September 4, the three boats, U-47, U-65, and U-101, had formed a north-south scouting line along longitude 20 degrees west. The weather was miserable: gale-force winds, towering seas. On September 5 Prien lost a man overboard. Early the next day von Stockhausen in U-65 reported contact with the convoy, but the weather and visibility were so bad he was not able to shoot. He shadowed, attempting to bring in the other boats. However, U-101 reported serious “engine defects,” forcing Frauenheim to abort to Lorient. That left only U-47 and U-65 to attack the convoy, which had picked up its local escorts: two destroyers, two corvettes, and three trawlers.

That same evening, September 6, in heavy seas, Prien made contact with Slow Convoy 2 and tracked. Later that night he attacked on the surface and sank three of the fifty-three ships: two British freighters, Neptunian, 5,200 tons, and Jose de Larrinaga, 5,300 tons, and the Norwegian freighter Gro, 4,211 tons. Owing to the weather and other factors, von Stockhausen in U-65 was unable to get into a favorable shooting position and could not attack.

As the convoy steamed eastward toward the North Channel, Prien doggedly tracked and radioed positions. Late on the morning of September 9, south of the Hebrides, he sank a fourth ship, the Greek freighter Poseidon, 3,800 tons. Responding to Prien’s reports a few hours later, Kuhnke in U-28 came up and sank one ship, the 2,400-ton British freighter Mardinian. The bulk of Slow Convoy 2—forty-eight ships and the seven escorts—reached North Channel without further damage.

Prien, having sunk a total of six ships and, he believed, damaged one, had only one torpedo left. Since he had been on patrol only fourteen days and still had an ample supply of fuel, Dönitz directed him to go west to 20 degrees and replace the damaged U-124(Schulz) on the weather-reporting station. Doubtless Prien found this assignment unappealing—the boat had yet to experience the delights of Lorient—but he carried it out without complaint. When relieved on station, the U-124 headed for Lorient. On September 10, Berlin gloatingly announced Prien’s claims: six ships for 40,000 tons sunk, one damaged.

Günter Kuhnke in the VII U-28, low on fuel, found and tracked another convoy, Outbound 210. In the early hours of September 11 he attacked on the surface, firing at what he believed to be two tankers and a freighter. He claimed the damaging of one 10,000-ton tanker and the sinking of two freighters for 13,000 tons. Postwar analysis credited him with damage to a 4,700-ton British freighter and sinking a 2,000-ton Dutch freighter. Critically low on fuel, Kuhnke headed for Lorient, claiming a total of five ships for 30,000 tons sunk on this patrol. With these and past overclaims, Kuhnke qualified for a Ritterkreuz under the relaxed criteria and it was awarded when he reached Lorient. His confirmed score at this time—all on U-28—was thirteen ships for 56,272 tons.

Kuhnke’s return left two of the August Atlantic boats in the hunting grounds: U-47 (Prien) on weather station with one torpedo, and U-65 (von Stockhausen). The latter had sailed from Germany on August 8, canceled the special mission to land agents in Ireland and aborted to Brest with mechanical defects, refueled in Brest and resailed, and found convoy SC 2, but had not yet fired a torpedo.

To this point—September 15—the thirteen Atlantic boats sailing from Germany in August had sunk a total of forty-four confirmed ships for about 230,000 tons, a decline to an average of 3.4 ships per boat per patrol, but still impressive. Five skippers—Oehrn, Prien, Schepke, Endrass, and Rösing—had accounted for two-thirds of the sinkings (twenty-nine). Two boats sailing in August had been lost: U-25 (Beduhn) and U-51 (Knorr). The base at Lorient had enabled Oehrn in U-37 to remount his aborted patrol to good effect, but otherwise it had yet to make any substantial impact on the U-boat war.

During August the ducks of the Emsmann Flotilla mounted six patrols to the Atlantic from Germany, Norway, or Lorient. They sank a total of seven ships for 32,000 tons. One duck, U-57, commanded by Erich Topp, age twenty-six, sank three of the seven ships (for 24,000 tons), but was herself rammed and sunk by the Norwegian tramp Rona on September 3, while entering a lock in the Kiel Canal. Six men died in this mishap but U-57 was salvaged, and Topp and the rest of the crew were assigned to commission a new VIIB. On August 31, the duck U-60, commanded by Adalbert Schnee, age twenty-six, torpedoed the 15,300-ton Dutch liner Volendam, which was transporting 321 British children to Canada, but the damaged ship was towed to port and all the children were saved.

British tanker losses remained worrisome. During the months of July and August, the oceangoing U-boats had sunk six for about 44,000 tons, the duck U-61 one. The duck U-57 had accounted for another, the 7,500-ton British Pecten. In addition, the Italian submarine Malaspina sank the 8,400-ton tanker British Fame near the Azores, and the U-A, on patrol off West Africa, sank yet another, the 5,800-ton Norwegian Sarita* Total Allied tanker losses in July-August: ten.

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