Black May (58 page)

Meanwhile, on 12 June, AOC-in-C Air Marshal Slessor canceled Operation Derange and ordered the establishment of two new search ribbons, code-named “Musketry” and “Seaslug.” Throughout the remainder of June and all of July, Coastal aircraft made those ribbons a killing zone; during July alone eleven boats, sailing either individually or in company, were sunk in the Inner and Outer Bay, two others were damaged. The only relatively safe U-boat transit route that remained was the Piening route, named after Kptlt. Adolf Piening (U-155), who pioneered it. This was a difficult and time-consuming coast-hugging course along the northern coast of Spain.

After four more boats in the Bay were sunk during the first two days of August, Donitz threw in his hand and declared a retrenchment. He
dispersed the groups that were then on passage, recalled six boats that had just sortied, made the Piening detour mandatory, and canceled his maximum submergence at night standing order of 27 April. Boats must thenceforth spend the minimum possible time on the surface day or night when transiting to and from base. There was to be no more seeking out gunfights with aircraft. During the ninety-seven days while the nighttime submergence order was in effect, Coastal Command aircraft in the Bay sank twenty-six U-boats and damaged seventeen—a rate that worked out to one boat destroyed every 3.7 days.
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The rate was never to be as high again, as Dönitz practiced thereafter a policy of extreme caution. The 97-day slaughter was a great victory for Coastal’s No. 19 Group, and Air Marshal Slessor took full credit for it in language that showed that he was still smarting from the impertinence of the “slide-rule strategists” Stephen Raushenbush and Evan Williams in asking for 160 and 190 additional aircraft, respectively, for the Bay Offensive. We won the victory with what we already had, Slessor tartly pointed out:

There are two assertions here with which one might take exception. While taking nothing away from the leadership qualities of Slessor, Bromet, and other commanding officers in Coastal Command, and certainly nothing from the impressive courage and skill exhibited by the airmen themselves, if the war was to be won on the basis of these attributes alone, the decision just as easily could have gone to Dönitz and his U-boat men. The problem for the Germans was never weak leadership or quailing sailors. It was obsolete equipment and the criminal negligence of their technological establishments to do such things as get a 10-centimeter G.S.R. to the boats immediately upon learning the secrets of the
Rotterdam Gerät.
One remembers what Captain
Gilbert Roberts had told Commander Peter Gretton in the Tactical Unit at Liverpool (chapter 4): war at sea had changed; courage and endurance were no longer enough; victory depended increasingly on advanced technology. The Germans were simply too late off the mark with
Naxos-U
and Type XXI.

Again, one may take exception to Slessor’s statement that the 160 or 190 additional aircraft were never needed for an effective campaign in the Bay. He overlooks the fact that operations analysts such as Raushenbush and Williams had to take the pessimistic perspective (as in the recent Persian Gulf War, when no analyst came close to predicting the rapidity of the ground campaign). Neither Raushenbush nor Williams could have responsibly assumed that the Germans would take an astonishing six months to get an effective G.S.R. in their boats. Their dereliction was simply not predicted. The victory came easier than assumed and at the expenditure of fewer flying hours because the surfaced U-boats made helpful sightings or radar blips.

Not originally a supporter of the Bay Offensive, which he once consigned to the status of a “residuary legatee,” Slessor thought that overall, the protection of threatened convoys offered more opportunities for destruction of U-boats. In principle he was right. In the locating of U-boats, Bay patrols consistently took second place to overflights of endangered convoys.
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But what must be considered, if killing U-boats was one’s first priority, is that there was a finite supply of endangered convoys, given Dönitz’s practice of massing U-boats against a few convoys rather than sending smaller numbers of boats against many convoys. Beyond a certain point, allocating more aircraft for convoy protection would not lead to the sinking of more U-boats, though it might have saved more merchant ships by forcing the U-boats down.
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In assessing the air war against U-boats in his autobiography, published in 1956, Slessor was eager that the reader know that many more boats were destroyed by RAF aircraft in 1942 and 1943 than were disposed of in that period by Royal Navy surface escorts. He particularly rejected Winston Churchill’s characterization of the RAF bomber as “an equal partner with the surface ship.”
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He also separated himself from the Prime Minister’s tribute to “M.A.C. ships”—these were
Merchant Aircraft Carriers, British conversions from grain ships and tankers that embarked three to four Swordfish each, and were not classified as warships, but gave morale-building air cover to 217 convoys—which, Slessor pointed out, did not sink a single U-boat (although he might have been gracious enough to acknowledge that no merchant vessel was ever lost in a convoy that was protected by a MA.C. ship). He was similarly dismissive of Churchill’s assertion that the hunterkiller groups formed around escort carriers such as U.S.S.
Bogue
were “the most deadly” enemies of the U-boats. While he complimented the “brilliant success” of CVEs U.S.S.
Bogue, Card, Core, Block Island,
and
Santee
—“household words,” he called them—he felt constrained to point out that of the 771 U-boats that were sunk by Allied action, only twenty were sunk by the hunter-killer groups, while 255 were dispatched by shore-based air (not including 17 sunk by RAF-laid mines and 66 destroyed by bombing in port).
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And as for the seventy-two American VLR aircraft that he had tried to obtain, at the A.U. Committee’s urging, “we never did get [them],” he wrote. “Actually as it happened it did not make much difference because we were able to defeat the U-boat by ourselves.”
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A more recent summation of U-boat losses to aircraft has been compiled by Air Commodore Henry Probert. Excluding losses in the Mediterranean and Indian Ocean, he finds that of 772 boats sunk in the Atlantic, Arctic, and British home waters, 305 were destroyed by Allied shore-based aircraft acting alone (Coastal Command’s share being 173) and 28 by joint action between shore-based aircraft and naval vessels (Coastal’s share being 21). Examining the remainder, he finds that fifty-two boats were destroyed by bombing attacks made on ports by RAF Bomber Command and the U.S. Army Air Force; that seventeen were sunk by RAF-laid mines; and that U.S. and Canadian maritime aircraft accounted for most of the rest.
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In a more general listing of causes, Captain Roskill estimated that 288 U-boats were sunk by Allied aircraft (excluding bombing raids), that 246 were sunk by Allied surface craft, and that 50 were destroyed by joint action of aircraft and surface vessels. There are obvious differences between and among these estimates.
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Probert numbers the RAF fatalities suffered in the ASW campaign at 5,866, 1,630 of them from the Dominions and European allies.
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Royal Navy casualties for all theaters were 50,758 killed, 820 missing, 14,663 wounded, and 7,401 taken prisoner. Though it is difficult to establish the breakdown for ASW alone, official RN historian Captain Roskill states that a “very large proportion” of the casualties came from that category. Furthermore, 102 members of the Women’s Naval Service (Wrens) were killed in all theaters, and another twenty-two were wounded.

Of the 830 U-boats that saw action in all areas, 480 were sunk in the North Atlantic, the Northern Transit Route, and British Home Waters. Casualty lists give 27,490 as the number of German U-boat men who were killed out of the 39,000 who sailed on operations—a startling 70 percent. (Some 5,000 more were taken prisoner.) It was the greatest mortal loss experienced by any single arm of any of the belligerent nations. During the final months of the war, when it was near-suicidal for a U-boat even to stand out to sea, crew after crew did so nonetheless, without demurral or complaint. In 1959 Roskill observed: “Whatever one may feel about their methods of conducting war, the morale and stamina of their crews only very rarely wavered, let alone collapsed.”
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The month of May 1943 has many claims on history, chief among them the epic Battle for ONS.5, which deserves to take a prominent place in the pantheon of naval victories. It was also the month when mastery of both shore-and carrier-based aircraft over the pre-Type XXI submarine was established; when sea warfare was altered by the first successful introduction of airborne acoustic homing torpedoes and rockets; when, arguably, operations research had its greatest impact on actions at sea; when HF/DF and 10-centimeter radar had their efflorescence; and, of course, when the largest number of U-boats to that date in a single month—forty-one—sank into the Atlantic pit.

It would not be prudent, however, to select May 1943 as the first month when the Battle of the Atlantic turned against its makers. The Allied triumphs in May came as the sum of processes that were gradual and cumulative, as we understand when we consider: the intensive
training of RN and RAF personnel and the long months of hard experience at sea or in the air that gave them their winning edge; the time-consuming calculations of boffins; the development of new tactics; the invention, manufacture, and installation of new weapons and devices; the sharpening of leadership at all ranks; the tenacity of merchant mariners who, except for the U-boat crews, faced the greatest danger, but never flinched; the growing industrial output of American shipyards and factories; the mines sown by RAF aircraft across the Baltic workup area in 1942 that seriously disrupted the training of many of the U-boat crews that would appear at sea in May; the refusal of Allied warships and crews to grow faint after the setbacks of March; and the resolute spirit of sailors and airmen who fought the U-boats to a draw in April. All those factors from months prior to this month, taken together, conspired to make May the crucible it was. What happened in the black month did not spring suddenly from the brow of Mars.

Nor would it be true to say that May was the start of a descending slope that led the U-Bootwaffe ineluctably to the abyss, for that start could be dated from the summer and fall of 1941, when the U-boats’ tonnage per day at sea first began to tail off, never to recover; or, later, from the formal entry of the United States into the war on 7 December 1941, when, with their vast industrial capacity, the Americans doomed Hitler’s sea war in the same way that the Russians, with their manpower as well as industry, doomed his land war. Still, the U-boat was a serious threat and had to be beaten, and it
was
substantially beaten, in May, in a victory that, it bears repeating, was the culmination of many months, not days. Similarly, the historian cannot point to any one person who was solely, or even predominantly, responsible for the sea and air successes of that month—not, positively, to Churchill, Horton, or Slessor alone, not to Winn, Blackett, Gretton, or Oulton, on the Allied side; not, negatively, to any individual decisions or actions taken that month on the other side, by Hitler, Dönitz, Godt, or any of their U-boat Commanders. Rather,
team
fought
team.
To the death. And that was what some of the U-boat officers called the month:
das grosse U-boot-Sterben
—“the Great U-Boat Death.”
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Following the conclusion of May, one individual Escort Group
Senior Officer did come dramatically to the fore, and from 1 June forward his name became identified in the popular mind with the mopping-up period. He was Captain Frederic John Walker, R.N., an old salt horse and proven U-boat killer who had spent much of the previous eleven months being “rested” in a staff job. Back at sea as SO of Second Escort (Support) Group in the sloop H.M.S.
Starling
, he commanded three other sloops whose ranks and ratings, like those of
Starling,
were trained to a fine point in his innovative “creeping attack” scheme. In this tactic one sloop, usually
Starling
, positioned herself at 1,000–1,500 yards from a submerged U-boat detected by asdic and stalked it at the U-boat’s speed. Eventually, Walker directed one or more sloops to take station ahead and attack with D/Cs—sometimes as many as twenty-six—across the course of the U-boat. No boat that was caught in Walker’s vise ever survived the experience, including U-202 (Kptlt. Günter Poser), which he stalked and attacked from 1213 on 1 June until 1212 on the 2nd, when, with both batteries and oxygen exhausted, the boat surfaced to be destroyed. Under his direction fourteen boats altogether were destroyed before his untimely death by stroke on 9 July 1944. To an adoring British public who acclaimed him Britain’s “ace U-boat killer,” Walker had modestly answered that that title was owed instead to his “Thousand British Tars.”
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Those Thousand Tars may stand fittingly as a symbol of the huge numbers of people who were required to defeat and then to mop up the U-boat fleet. It has been estimated recently that it took 100 persons engaged in ASW to match every German U-boat man, and 25 warships and 100 Allied aircraft to match every U-boat.
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For those millions of British, American, and other Allied personnel, uniformed and civilian, men and women, at least for those who were aware of it as a spinal event on the order of Stalingrad or Kursk, May must have been a source of enormous gratification in exchange for all the operational or work hours they had invested to defeat Bismarckian blood and iron.
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