Black May (38 page)

Furthermore, in denigrating slide-rule strategy in his autobiography, he seems to have forgotten that in the foreword he wrote to Professor Waddington’s 1946 book,
O.R. in World War 2,
he praised “strategy by slide-rule” by name, and acknowledged that “No one who knows the true facts can have any doubt that a great deal of the credit for what is perhaps still not generally recognised as the resounding victory it was, namely the Battle of the Bay and the defeat of the U-boat in 1943, is due to men like Blackett, Williams, Larnder, Baughan, Easterfield and Waddington himself.”
²⁵
Raushenbush’s name he seems not to have known, although the name appears prominently in the Stark Plan, where he is identified as its author, and that was the Plan whose calculations Slessor acknowledged to the A.U. Committee near the end of May, as will be seen, as having been vindicated by events in the Bay.
²⁶

Slessor’s letter to the A.U. Committee of 4 April was not taken up by that body. Instead, during the days that followed, Slessor was persuaded to make a complete volte-face. It may have been the Air Ministry or the Admiralty, or both, whose heavy hand wrought this singular reversal—the record does not say—but when the time came for the A.U. Committee to petition the U.S. Joint Chiefs of Staff for additional longrange bombers for the Bay, it was Slessor who was tapped to draft the document. With the fervor of a convert, brought to his new faith by either conviction or thumbscrew, Slessor gave the case for the Bay Offensive its most striking language yet. Signed by him, First Sea Lord Pound, and Admiral Stark, the telegram to Washington read, in part:

In their telegram the three signers called the Bay “second only to the convoy routes” as a strategic priority in the Battle of the Atlantic. They noted that 150 “first-line” aircraft were already engaged in the Bay Offensive, and that thirty to forty longand medium-range aircraft could be added to the force through recall of a Leigh Light squadron from Gibraltar, new construction, and borrowing. These new figures led to a revision of the number of additional aircraft needed. Hence, to make up the 26o-aircraft requirement stipulated in both the Stark and Admiralty Plans, Coastal sought from the U.S. Joint Chiefs six squadrons totaling seventy-two long-range anti-submarine aircraft, drawn, the signers underscored, “from the forces already allocated [at the Atlantic Convoy Conference in Washington the previous month] to the Atlantic theatre.” At that conference the U.S. side predicted that 217 aircraft of suitable type and equipment, including 56 VLR, would be available “in excess of’ immediate Atlantic requirements.

It was important, the signers added, that the squadrons be made available “at the earliest opportunity” so as to take advantage of the period when the U-boats were without a 10-centimeter search receiver. (The A.U. Committee Minutes of their 14 April meeting, which contain a first draft of this communication, indicate that the Committee backed the four-month offensive proposed in the Stark Plan as against the twelve-month offensive proposed by the Admiralty.) The six squadrons would be accommodated at bases in southwest England. A
reinforcement on that scale, the signers believed, “might well have results decisive to the issue of the Battle of the Atlantic.”
²⁸

But Washington’s reception of the British telegram was cool. While sympathetic to the plans for an intensive operation in the Bay, the Joint Chiefs responded on 1 May, they had to report, regrettably, that the aircraft that they had predicted to be “in excess of” immediate requirements did not and would not in fact exist. The number of ASW aircraft cited in the document produced by the Convoy Conference, Admiral King explained, was based on figures “the origin and accuracy of which could not be entirely vouched for and which apparently had raised hopes as to the availability of aircraft which facts did not now warrant.”
²⁹
This reply, appearing so casually dismissive of a formal Allied agreement, caused understandable resentment in England, where a new telegram was drafted asking, if the numbers produced by the U.S. to the Convoy Conference were in error, would the U.S. kindly send the correct figures as quickly as possible?

Another and longer interval ensued before King and the other Joint Chiefs replied, in part because these matters were not exactly in the foreground of King’s interests at the time, since he was then engaged in one of the most contentious interservice rows of the war over the question, Who would control American anti-submarine air squadrons, the Navy or the Army Air Force Anti-Submarine Command? Slessor, who would personally observe these bitter turf battles during a visit to the States in June, said later: “The whole atmosphere in Washington was poisoned by inter-service jealousy and suspicion.”
³⁰

On a belief that the reader would not want to be wearied by a recital here of that tedious tangle of disputes, which resulted in the Army’s withdrawal from anti-submarine work in the fall of the year, we shall leave that to the parti-pris literature and say simply that, try as Slessor did, he never succeeded in obtaining the seventy-two aircraft requested for the Bay; and it was not until October (!) that he could count any appreciable number of reinforcements from the American side.
³¹
In that month Coastal had three U.S. Army and one U.S. Naval operational squadrons based at Dunkeswell in Devonshire and two U.S. Naval squadrons that were still working up at St Eval.
³²
But by October,
it must be recognized, the planned Second Bay Offensive was over, having been waged by the aircraft that Coastal already had in hand, and the crisis of the U-boat war had passed.

Before the telegrams began passing between London and Washington, and Army and Navy air interests began crossing swords across the Potomac River (though invited by the Army’s War Department in 1942 to occupy all of the second floor and part of another in the newly erected Pentagon, an invitation that Secretary of the Navy Frank Knox readily accepted, the Navy Bureau Chiefs, not wanting to live cheek by jowl with the Army or Army Air Forces, objected strongly to moving there, and would not do so until 1948), Coastal had mounted another Bay trial, Operation Enclose II, which ran from dusk on the 5th to dawn on the 13th of April. With fewer aircraft (86) than were used in the first Enclose (115), but with three more L/L Catalinas of No. 210 Squadron, the operation was positioned over the same ribbon of sea as before and with the same deceptive 1.5-meter A.S.V. flooding at night.

During the period, twenty-five U-boats transited the ribbon (as against twenty-eight estimated). The total of 980 flying hours produced eleven sightings, more of them at night than in daylight for the first time, and four attacks, leading to the nighttime sinking of U-
376
(Kptlt. Friedrich Marks) by L/L Wellington “C” of 172 Squadron, and damage to U
-465
(Kptlt. Heinz Wolf) by Catalina “M” of 210 Squadron Fewer aircraft and fewer flight hours had produced the same results as those achieved by the original Enclose. And other U-boat crews, having affected narrow escapes, no doubt experienced what Raushenbush called “sheer funk.”

With the demonstration of higher efficiency in the repeat of Enclose, it was decided, even before that operation was concluded, to launch a full-scale, long-term intensive patrol over a larger ribbon between 8½° and 12° W under the code name Operation Derange. A total of 131 individual aircraft, all that were available at the moment, though well below the 260 considered necessary by Raushenbush and Williams, were committed to the new operation, which was to begin at dawn on 13 April and to continue “until further notice.” Included in
that number were three new squadrons, a rocm. L/L Wellington squadron, No. 407, an ordinary Wellington squadron, No. 311, and a Whitley squadron, No. 612.

Up to the end of April, eighty-one U-boats crossed the Derange ribbon, either inbound or outbound, and during that period a total of 2,593 day and night flying hours resulted in thirty-six sightings and twenty-two attacks. The percentage of sightings made to hours flown represented no improvement over Enclose II. But one kill was made and two outbound boats were so badly damaged that they were forced to return to Brest and St.-Nazaire, respectively. The 10cm.-equipped Liberator “D” of 224 Sqdn. dropped six D/Cs on the previously damaged U
-332
(Hüttemann) 25 seconds after she had dived, sinking her, northwest of Cape Ortegal, Spain, on the morning of the 29th. Damaged were U
-366
(Kptlt. Hans Hornkohl), depth-charged by L/L Wellington “R” of 172 Sqdn. on the night of the 26th; and
U-437
(Oblt.z.S. Hermann Lamby), depth-charged by L/L Wellington “H” of 172 on the night of the 29th.
³³

The principal effect of the twenty-two Derange attacks in April, however, was to induce exasperation at BdU, where the Operations staff had grown weary of reports from Commanders during Enclose, Enclose II, and now Derange that despite their Fu.MB (Metox) gear, they were being surprised at night like deer in a car’s headlights.
³⁴
On 27 April, Admirals Donitz and Godt made a fateful decision, which they signaled to all Commanders. Standing War Order No. 483 was forthwith revised to require boats (1) to maintain
maximum submergence at night
through the Biscay transit area, and (2) to
fight it out
with aircraft on the surface in the daytime if surprised while charging batteries. This decision would lead to heavy U-boat losses during May and the summer months—twenty-six kills and seventeen U-boats damaged in ninety-seven days and nights—causing it to be called by historians “a major tactical error,” resulting from, as Slessor represented it, “the stupidity of the enemy.”
³⁵

British aviation historian Alfred Price argues that in April only two out of a dozen anti-submarine squadrons in Air Vice Marshal Bromet’s No. 19 Group were fitted with both Leigh Light and 10-centimeter radar, and hence were not numerous enough to cause more than the
loss of “a few U-boats to air attack without warning.” But in April the ratio of nighttime L/L-Iocm. hours flown inside the Enclose and Derange ribbons to nighttime hours flown by unequipped aircraft was 777 to 428, and L/L Wellingtons made seven night attacks without Metox warning between 26 and 29 April, resulting in two outbound U-boats seriously damaged,
U-566
and U
-437
(see above), which had to abort their departures.
³⁶

No doubt this nighttime coverage got BdU’s attention, and the Dönitz/Godt duumvirate decided that placing their battery-charging boats on the surface at night under the sudden surveillance of searchlights was a more perilous course than was deploying them on the surface in daylight, when at least their lookouts had a reasonable chance of sighting the enemy’s approach in time to bring anti-aircraft armament to bear. They would then have both a warning and a defense, neither of which they had under the lights. Perhaps Dönitz and Godt were not as “stupid” as Slessor thought. They were simply wrong. If the plan was to surface during the daylight hours, then the U-boats should have been instructed to dive upon sighting aircraft. They did not have the firepower to fight back successfully. And one downside to maximum submergence, whether by day
or
by night, was greatly increased transit time, which translated into reduced opportunities to sink shipping.
³⁷

In making the decision to spend the battery-charging hours on the surface in daylight, Dönitz and Godt likely were influenced by
U-JJJ’S
flak success against a Wellington (see above) and
U
-338’s success in downing Halifax “B” of 502 Sqdn., both in March; and by U-79/s protracted machine-gun defense on 12 April that forced Liberator “M” of No. 86 Squadron to break off an attack—details of which BdU transmitted to all boats as an incentive. (Three L/L Wellingtons were unex-plainedly lost in the Bay during April.) But these three successes, it turned out, were thin reeds on which to base so dangerous a general policy.

And so, on the cusp of May, the Battle of the Bay entered a phase that had not been predicted by either Raushenbush or Williams, a phase in which the secret use of 10-centimeter radar counted less than either boffin had anticipated, since the night had effectively been taken
away from the equation.
³⁸
Though Bromet’s No. 19 Group maintained night patrols at about the same level from April through August, night sightings decreased sharply at the end of April and the battle from 1 May forward became mainly one of
mano-a-mano
combat in daylight, and let the metal fall where it may.
³⁹
The essential point that should not be lost here is: displaced by the German decision as the top-drawer weapon in the Bay, the Leigh-Lighters nonetheless had proved for a second time that they were the controlling threat. Even now, in a passive role as menace-in-being, by slowing the passage of U-boats through the Bay, they saved numerous merchant ships from torpedo-wrought deaths.

Bromet’s bombers were ready for this May battle. Based mostly in Devon, Cornwall, and South Wales, they had trained to near-perfect pitch, absorbing the lesson from O.R.S. in 1942 that it was not the weapon but the man that counted. And they had mastered the tactical doctrine long earned by O.R.S. calculations and combat experience. Foremost in anti-U-boat operations was sighting. Two lookouts, the doctrine held, must keep a continuous watch from ahead to 90° on either side of the aircraft, and to prevent errors through fatigue, they should be relieved every half hour.