by Paul Kennedy
One response, which went back to almost the beginning of the war, was to make a simple division between “fast convoys” and “slow convoys.” Much flowed from this, including the different nomenclature (“SC” was a slow convoy, “HX” a faster one, the latter usually coming out of the great harbor of Halifax, but also from New York itself). These convoys could leave from separate ports and be timed to arrive in the United Kingdom (or, on their return journeys, into East Coast harbors) on different days. Slower escorts such as sloops and armed trawlers were assigned more often to the slower convoys. The schedule of aerial patrols could be arranged accordingly. Allied warships dispatched to join one convoy in midocean might be instructed to help another one if it came under heavier attack. To be sure, and to the fury of every escort commander, all convoys, whether fast and slow, would have their stragglers—how could it not be, with forty, fifty, or sixty oddly assorted ships in a single group? Overall, dispatching large convoys and dividing the merchantmen into fast and slow concentrations made a lot of sense. Yet what would happen if the number of U-boats was simply too great?
Already by March 13, 1943, B-Dienst had evidence that the slow convoy SC 122 (fifty-one assorted vessels, with four or five close escorts) had set off from New York. It was to be followed a few days later by the fast convoy HX 229 (forty-one vessels, with four escorts), from the same port. The latter fact was not clear to the Germans at this time, but the intelligence nevertheless gave Doenitz plenty of time to order his western patrol group to ready for an attack, while also instructing additional U-boat groups to move westward, toward the key zone in the middle of the ocean. An examination of the route charts, losses, and reports of the convoys (there actually was a further fast convoy of twenty-five ships, HX 229A, well to the north, off Greenland, at this time), and especially of Rohwer’s reconstruction of the maneuvers of the individual U-boats, leaves the reader with a sense not only of the complexity of this contest but also of its enormous size. Correlli Barnett has it right: “It could be said that for the first time an encounter in submarine warfare attained the scale and decisive character of the great fleet battles of the past.”11 In fact, one would probably have to go back to the grim multiday fights of the mid-seventeenth century between the Dutch and British navies to find a good historical equivalent.
The German attack upon these two convoys seemed to unfold like clockwork, although serendipity played a role, too. Because of engine trouble, U 653 was slowly heading westward to a relay point when it saw the approaching convoy HX 229 on the horizon, steaming toward British harbors. Its captain, the bemused though resourceful Lieutenant Commander Feiler, dived under for a long while as the entire convoy passed over it. When he resurfaced, the ocean was clear; the convoy had steamed on, and U 653 could send the critical message to Doenitz’s headquarters, which then took immediate action. Twenty-one submarines responded to that news, a clear testimony to the way that electronic communication was changing the art of war.12
The seas were terribly rough, but the wolf packs pressed in, sensing that this was a great opportunity. The clear, moonlit night of March 16–17 truly was a night of the hunter, for which many merchantmen were to pay the price. The attackers were also advantaged by the fact that on that same night the HX 229 escort commanders decided to slow the convoy in order to pick up stragglers and, by doing so, unwittingly bumped into the first cluster of U-boats. Had that decision to slow down not been taken, the submarines “would certainly have passed by to the stern.”13 But once the convoy had been detected, there was little that its escort commander, Lieutenant Commander Luther in the destroyer HMS Volunteer, could have done to lead his flock to safety. His direction finder had located two U-boats 20 miles away and closing, so he had dispatched another escort to drive them away. But if one group of U-boats had missed their target, others surely would not. By this time, both the American and British admiralties were picking up U-boat signals from all around the convoy, so alterations in course to avoid one cluster of attackers simply brought HX 229 closer to another.
Thus, around ten o’clock on the moonlit night of March 16, the captain of U 603 found himself watching an entire Allied convoy slowly steaming by, with its remaining four escorts widely separated. By this stage Doenitz had his submarines equipped with the deadly FAT torpedoes, which ran straight at 30 knots over a given course, and then zigzagged in order to counter the opponent’s evasive actions. Since the horizon was filled with targets and U 603 was able to come as close as 2 miles (3,000 meters), the zigzagging capacity was probably unnecessary on this occasion. The submarine fired its three front torpedoes, then its rear torpedo, and had the satisfaction of hearing a large detonation before slipping back under the waves; the freighter Elin K. sank within four minutes. With the convoy escorts now distracted by picking up the ship’s survivors and looking for U 603, the convoy’s northern flank was virtually uncovered. This gave Captain Lieutenant Mansek in U 758 the freedom to fire off torpedoes like a cowboy in a Western saloon. “At 2323 hrs Kptlt Mansek fired a FAT torpedo at a freighter of 6000 tons in the starboard column, one minute later a G 7e [torpedo] at a freighter of 7000 tons, at 2325 hrs a FAT torpedo at a tanker of 8000 tons behind her and at 2332 hrs a G 7e at a freighter of 4000 tons”: four separate torpedo launches in nine minutes.14 The Dutch freighter Zaaland and its American neighbor James Oglethorpe were hit, the first settling in the sea and the second, controlling an onboard fire, temporarily limping on (it would be finished off by U 91 later that night).
The Allied merchant ships were, in effect, running a gauntlet, and even those steaming in the inner columns were likely to be hit if a torpedo passed between the outer lines. What did this mean more generally? There were the two lost merchant ships themselves, of course, and thus two fewer in the limited tally of hulls that could go back and forth across the Atlantic. And then there were the crews, although many of them were picked up by the destroyer HMS Beverly and the corvette HMS Pennywort—at one stage in this chaotic night, incidentally, there was only one escort with the main convoy for a while. But perhaps the real point to notice was that the Zaaland was carrying a cargo of frozen wheat, textiles, and zinc, and the James Oglethorpe was transporting steel, cotton, and food in its hull, and aircraft, tractors, and trucks for the U.S. Army on its deck.
It is difficult, probably impossible, sixty-five years later to enter the mental world of the commanders of those four naval escorts, who were looking after such an immense responsibility (they were about to be joined that day by a fifth, HMS Mansfield). They did not occupy the mental space of, say, Alanbrooke, experiencing the larger worries and frustrations that filled his diaries at Casablanca and in these later desperate months.15 Nor did they occupy the world of the common soldier, sailor, and airman, almost all of whom had been culled from civilian life into a new existence of danger, hardship, and terror in this seemingly everlasting war. The convoy escort commanders operated at the middle level—just like the German U-boat commanders—and had enormous obligations to fulfill, setbacks to deal with, and losses to swallow.c Yet it was upon this middle level that the fate of the war now depended.
At half past midnight on March 17, U 435 put a torpedo into the American freighter William Eustis, which stopped immediately and began to list. The convoy commander, Lieutenant Commander Luther, having just returned to the main body and aware that his fellow escorts were picking up survivors several miles behind, swept his destroyer, HMS Volunteer, to the rear of the convoy. There he found the wrecked William Eustis, with its lifeboats launched but with many of the crew swimming in the water in different directions, crying for help. This was one of those occasions when there were no obvious, good solutions—only bad ones and even worse ones. Rejecting the pleas of the master and chief engineer of the merchant ship (who had scrambled on board the destroyer) that a rescue attempt be made at dawn, Luther took on as many survivors as he could find and then, fearing a U-boat team might board the beleaguered vessels and seize vital codes and papers, he depth-charge
d the William Eustis and steamed back to the convoy.
It was still only 2:50 in the morning, and the overworked destroyer had just caught up once more with the convoy when it saw the distant blast of another freighter going down. Two hours later Captain Lieutenant Zurmuehlen of U 600 achieved one of the most accomplished torpedo attacks of the Second World War, firing a salvo of four FAT torpedoes from the bow, and then one from the rear tube, at the totally unprotected starboard flank of the convoy. Within minutes the British freighter Irena and the whaling depot ship Southern Princess had each been hit by one torpedo, and the American freighter Irene du Pont by two. HMS Mansfield rescued survivors. As dawn broke, all that really could be done was finish off the abandoned, wrecked merchant ships. The corvette HMS Anemone did half that job, while U 91, arriving on the scene an hour or two later, completed the messy task. The British escorts were now full to overflowing with rescued crewmen.
Farther east, the convoy SC 122 had begun its own encounter with the furies. The fifty-one vessels enjoyed the protection of seven escorts, including the American destroyer USS Upshur and a specially equipped rescue ship, the Zamalek. At around 2:00 a.m. on this same dreadful night U 338 was racing westward to join the attack upon HX 229 when its commander, Captain Lieutenant Kinzel, saw a mass of ships on the horizon, a full 12 miles away; a hunter’s moon, indeed. Kinzel’s first two torpedoes mortally damaged the British freighters Kingsbury and King Gruffydd. The second salvo (also two torpedoes) tore into the Dutch four-masted freighter Alderamin and broke it into three pieces; it was gone in two minutes. In turning away from this mayhem, U 338 fired her stern torpedo at another nearby ship. The torpedo missed its intended victim but drove on through the middle of the convoy to the far end, where it blew a great hole in the side of the British merchantman Fort Cedar Lake. Five torpedoes, four ships.
As the next morning unfolded, the Allied naval authorities became aware that they were facing a double disaster: the gutting of two of their vital supply convoys plus the prospect that Doenitz was dispatching more and more U-boats into this great contest. The two convoys had not yet joined and would not do so until the night of March 17–18, but the overall picture was obvious. A great quantity of Allied merchantmen, seventy or eighty or more, and their cargoes were caught in the middle of the Atlantic, with a completely insufficient number of escorts, and with the enemy submarines massing for the coup de grâce.
But with the dawn came light, and with the light came aircraft. And there was nothing that terrified a U-boat commander so much as the sight, or even the noise, of an approaching Allied plane. It really was the rock-paper-scissors game. Merchant ships were horribly vulnerable to U-boats and their torpedoes, but U-boats, even those that decided to stay on the surface and fight, were seriously outgunned against aircraft. On many occasions, the submarine hardly had more than a minute or two to fire, because the aircraft came in so fast; the only thing the sub’s commander could do was dive, dive, dive … and wait for the depth charges. Catalinas, Liberators, Sunderlands, and Wellingtons were to them the scariest of the Allied weapons system, the Ringwraiths of the sky. This, after all, is why the U-boats waited to attack Allied merchant vessels in the mid-Atlantic air gap.
On March 17, 1943, that gap began to be closed. At the urgings of Western Approaches Command, the first few very long-range (VLR) B-24 Liberators were flown out of their base near Londonderry, Northern Ireland. For a number of reasons, all of RAF Coastal Command’s squadrons (in Northern Ireland, Iceland, the Hebrides, and Scotland) were at this time significantly understrength, but the Liberators could at least reach the closest convoy, SC 122. During the course of the day these aircraft sighted U-boats on numerous occasions and made six attacks on them before they had to return to base. No submarines were destroyed or even damaged, but they were repeatedly forced to dive. In fact, during that whole day the only ship in the convoy to be sunk (again, by the indomitable Kinzel, in U 338) was the Panamanian freighter Granville, carrying supplies for the U.S. Army.
By contrast, convoy HX 229 was not within the reach of aerial protection, and the few escorts actually with the main body of the convoy, or not catching up after rescuing survivors or chasing a sonar trace, were completely overworked. This allowed the attackers to destroy the Dutch Terkoelei and the British Coracero. As nightfall came, and with fine visibility, the U-boats moved in on the convoy once more. But then a B-24 appeared and in fairly quick succession sighted and depth-charged first a pair of submarines and then another group of three, and then—completely out of depth charges—machine-gunned a sixth. None of the subs was damaged, but all were unnerved. The Liberator had stayed eighteen hours in the air, two hours longer than the normal recommended time. However, quietness was not given to SC 122, which lost another two valuable ships, the Zouave (to a direct hit from U 305) and the Port Auckland (wrecked by the same submarine but probably finished off by Kinzel).
These daylight sinkings of two more merchantmen had sent HMS Volunteer racing to the starboard of the convoy, but its own direction finders had become defective, and the other few escorts were picking up survivors. One guesses that Luther had either great courage, great obstinacy, or both, but it was only with the sinking of the Terkoelei and Coracero that the convoy commander “thought the time had come to ask for help.” (One of the wonderful side benefits of reading the messages of these escort commanders, or a single ship’s captain, is the chance to marvel at their tendency to understatement.) It was at this point that one of the faster American merchantmen, the Mathew Luckenbach, decided to break free from the convoy and steam ahead, despite repeated messages from the escorts and the convoy commodore; she was sunk, with few survivors, two days later.
Even before Luther’s message for help, both admiralties decided to commit more resources to the battle. This was much easier for Doenitz, since he had fresh U-boats already in the Atlantic. The British planners faced a much tougher task, simply because there were a lot of other valuable convoys in the North Atlantic at exactly the same time. The two Gibraltar convoys KMS 11 (sixty-two merchantmen, with nine escorts) and KMF 11 (nine transports, with two escorts plus destroyers pulled from other duties) would probably have to fight their way across the Bay of Biscay, where they might face not only another cluster of U-boats but also the possibility of long-range German bombers; none of their escorts could be spared. Convoy ON 172 (seventeen merchantmen, with six escorts), south of Cape Farewell, was not only too far away but also in an area where another U-boat group was forming. And convoy ON 173 (thirty-nine ships, with six escorts), steaming far to the north of the battle, was very weak itself. Reinforcing corvettes dispatched from St. John’s were not fast enough to catch up until later, and the two U.S. destroyers ordered from Iceland were damaged by the heavy seas on March 17 and 18.
The same was true of Allied aircraft, so critically important and yet so few. Also, possessing at this time poor ship-to-plane contact, the Liberators, Sunderlands, and the rest often failed to link up with the convoys. So further Allied shipping losses occurred on March 18. One of them, with brutal irony, was the Walter Q. Gresham, among the very first of the new American-built Liberty ships whose mass production would eventually solve the shipping shortages; the second was another modern vessel, the Canadian Star. By the time the vastly overworked corvette HMS Anemone had picked up survivors from these two ships to add to her earlier rescues, she had 163 exhausted civilians on board, including six women and two children. Then she rejoined station and spent all the following night driving away U-boat attacks on HX 229. Sometimes the asdic worked, sometimes not; the Hedgehog grenades failed twice; and while the depth charges worked, by the time they had reached their preset depth the submarines had slipped away. A multitude of survivors slept on the Anemone that night; Convoy SC 122 was luckier in that it possessed a proper recovery ship.
By March 19 the great plot map of the North Atlantic that covered an entire wall of the Admiralty’s control room presented an extraordinary scene. Signals from enemy U
-boats were being picked up from virtually every quadrant of the ocean. The Gibraltar convoys were coming under heavy attack from submarines and aircraft as they passed the northwest corner of Spain. To the far north HX 229A had avoided the U-boats but crashed into a sea of icebergs. One extremely large Danish whaling ship (the Svend Foyn), carrying numerous civilian passengers, was settling in the icy seas, not too far from where the Titanic had gone down. The only consolation was that HX 229/SC 122 had at last reached the 600-mile range limit from Allied air bases in Northern Ireland and Iceland, and the battered crews of the merchantmen and their surface escorts could watch Liberators, Fortresses, Sunderlands, and Catalinas guiding the warships to the U-boats and joining in the attack. Some of the U-boat captains still persisted, however, including Kinzel, whose vessel set course for home only after it had been badly damaged by aerial depth charges. Two hundred miles to his rear, the captain of the less experienced U 384 was caught on the surface by a low-flying Sunderland and blown to pieces early on March 20. This was the only submarine lost in the entire, prolonged battle. By evening Doenitz had recalled his patrols.
By the following day the convoy commanders were starting to send some of the escort vessels ahead to safe harbor. The first ones, properly enough, were warships such as the Anemone, Pennywort, and Volunteer, carrying their hundreds of civilian survivors. All on board had been pushed to the extremes of human endurance. Forty-two of the sixty ships in SC 122 reached their destinations, as did twenty-seven of the forty ships of HX 122. The commodore (i.e., chief of the merchantmen) of the slower convoy laconically reported that it had been a normal Atlantic voyage “apart from” the U-boats.