On the 17th, Halifax “D” of 58 Sqdn. released six D/Cs on U-628 (Kptlt. Heinz Hasenschar), the shadower boat of the Battle for ONS.5, which was returning to base. The U-boat was not damaged. One attack was made at 1721 on the 20th, by Wellington “G” of 172 Sqdn., following an S/E contact. The identity of the target, depth-charged 40 seconds after submergence, is not known. On the 21st there were three attacks, all as the result of visual sightings. At 1459, Whitley “Q” of 10 Sqdn. O.T.U. attacked Us-634 (Oblt.z.S. Eberhard Dahlhaus) 21 seconds after submergence. This boat, which had been damaged in the Battle for ONS.5, was not damaged a second time. At 1756, Whitley “H” of the same squadron attacked a boat, thought possibly to have been U-230 (Kptlt. Paul Siegmann), 30 seconds after submergence. And at 2031 Liberator “D” of 224 Sqdn. attacked a boat, thought possibly to have been U-525 (Kptlt. Hans-Joachim Drewitz), 15–20 seconds after submergence.
Three more attacks came on the 22nd. At 1123, Halifax “O” attacked a boat, unidentified, 30 seconds after submergence; at 1154, Whitley “D” attacked a surfaced boat, unidentified; and at 1227, Whitley “G” attacked an unidentified boat 12 seconds after the conning tower had disappeared. The first of two attacks on the 24th was made by Whitley “J” of 10 Sqdn. O.T.U. at 1122 against a fully surfaced boat, unidentified, that offered no return fire. But such was not the good fortune of Sunderland “L” of 228 Sqdn., based at Pembroke Dock, which four and a half hours later encountered U-441, the first of two VIIC boats converted to anti-aircraft role (Flak-U-boot), the other being U-216.
In this modification a quadruple 20mm cannon was mounted on a raised platform before the bridge, two single 20mm cannon on the after end of the bridge, a 3.7cm gun on a raised platform abaft the bridge, and another “quad twenty” on an extension to that platform. The curtain of fire produced by that amount of armament was formidable. The task given U-441 (Kptlt. Götz von Hartmann), which sortied from Brest on the 22nd, was to operate entirely on the surface in the Bay, attacking Allied aircraft and giving cover to damaged boats unable to dive. When Sunderland “L” made her run in against the boat at 1400 she passed, bleeding, through a hail of fire. Pilot Flying Officer H. J. Debden managed to straddle the boat with his D/Cs before, fatally wounded, his “Queen” plunged into the sea. The entire eleven-man crew was lost. But U—441 was also badly wounded, and had to return to Brest, not to sortie again until 8 July. On the 12th of that month she was dived on by three cannon-equipped Beaufighters of 248 Sqdn., which killed ten U-boat men and wounded fifteen others, including the Commander, forcing the boat back to Brest again. Her sister boat U-256 did not put to sea until October, and, after one less than successful patrol, was reconverted to an attack role. The flak-boat idea was not working.
Attacks were made on a submerged boat on the 29th by Beaufighter “O” of 236 Sqdn., employing a new “R.P.” rocket-propelled warhead (see chapter 10); on a surfaced boat on the 30th by Liberator “G” of 224 Sqdn; and on a submerged boat, again on the 30th, by Halifax “E” of 502 Sqdn. All three attacks resulted from visual sightings. None was assessed as causing damage.
The last day of May was one on which, it could be said, No. 19 Group snatched the hood from the falcon. Seven different Derange aircraft made eleven attacks (including second attacks by individual aircraft) resulting in two U-boats destroyed and a third forced back to base. Liberator “Q” of 224 Sqdn. obtained an S/E contact in daylight and dropped six D/Cs on a surfaced boat, causing no visible damage. Fortress “A” of 206 Sqdn. scored the first success of the day, visually sighting a wake and then a surfaced U-boat at 1151. The aircraft attacked from one point abaft the boat’s starboard beam with six D/Cs, obtaining a straddle of two explosions on the starboard side and four on the port. During the run in two German crewmen were seen manning a gun on the bandstand (Wintergarten), but no fire was observed. Although the Fortress crew saw nothing more than a spot of oil in the explosion mark, British interrogators later learned from captured crewmen from the attacked boat, which was U—523 (Kptlt. Werner Pietzsch), sunk on 25 August 1943, that in A/206’s depth-charging she suffered damage to two tanks and had to return to base.
The coup de théâtre on the 31st was a joint attack by four aircraft on a U-boat first visually sighted on the surface in position 46°35’N, 10°40 W. Cloud was 5/10ths, bases at 3,000, tops at 5,000. The sea was moderate. Wind was 260° at twenty-five knots. Visibility was fifteen miles. Running parallel to the Biscay coast and creeping westward, Wing Commander Oulton of 58 Sqdn., seen before on the 7th and the 15th, was dipping his Halifax “R” in and out of the cloud base when at 1550 his flight engineer sighted “white horses” bearing 20° Red, distant six miles. Oulton altered course, climbed into the cloud, and increased revolutions per minute (RPMs) and manifold pressure. At four miles from the estimated position of the wake-making U-boat, Oulton dived out of the cloud at a steep angle so as to give the mid-upper turret gunner an opportunity to spray the U-boat’s tower and put the German gunners “off their job a little.”
After leveling off at 80–100 feet, Oulton made his run in from starboard quarter at an angle of 30° to track, dropping six Mark XI Torpex D/Cs set to shallow depth and spaced 86 feet apart, while the U-boat was still fully surfaced. Photographs later showed a straddle midway between the conning tower and bow. After getting off gun bursts, the rear gunner reported that as the explosion plumes fell away, the U-boat was observed to be “wallowing” in the D/C pool. Oulton circled tightly to port and returned to the scene from dead astern on a westerly course, firing rounds as he came and releasing three more D/Cs. When the spray subsided, the U-boat was seen to be stationary in the center of the D/C scum.
Out of D/Cs, Oulton circled around and made a gun run about 300 yards to port of the injured boat, firing from both the mid-upper and rear turrets. The U-boat was now lying beam on to sea at a northerly heading, surrounded by a large oil patch and considerable wreckage. Twice more Oulton returned to rake the boat with gunfire, now seeing individual crewmen emerge from the tower hatch and run along the deck. Soon there was answering 20mm fire from the boat, but it was inaccurate, and was quickly suppressed. On another weaving, up-and-down pass Oulton saw bodies lying on the bridge. He climbed to 3,000 feet and reported the action to St Eval, suggesting that a reinforcement be sent.
This was done, and at 1710 Halifax “J” of 58 Sqdn. homed in to the position on Oulton’s W/T. Since the pilot could not find the U-boat, Oulton led him down to it, then banked off about 200 yards on J/58’s starboard to give him covering fire. The U-boat was now circling to port. The J/58 pilot made an attack but dropped his six D/Cs 100 feet off-target. On a second attack run he missed again by the same margin. Oulton later said sympathetically that the pilot, young in age and experience, was “over-anxious.” The J/58 stayed around and poured about 200 rounds into the conning tower, on which five crew members were seen; then, at 1275, sighting a Sunderland at 180°, the pilot flew off to attract the flying boat by Aldis lamp signals to the scene. This was Sunderland “E” of 10 Sqdn. At nearly the same time a second Sunderland, “X” of 228 Sqdn., was sighted, and it too was invited to attempt a coup de grâce.
The E/10 swept in from 40° on the U-boat’s starboard bow and dropped four D/Cs that straddled the target. Previously able to maneuver, though trailing oil, the U-boat, now badly shaken again, lost way and stopped. The E/10 wheeled around for a second attack, which she delivered at 1747 from the starboard beam. Four more D/Cs descended on the stubborn boat. Three overshot, but one exploded about 30 feet distant from the “yellowish brown” hull, forward of the conning tower.
Sunderland X/228, nearby, watched E/10’s two attacks and then, at 1750, made one of her own, from the starboard quarter to the port bow, with four straddling D/Cs. She returned two minutes later with four more D/Cs, which entered the water forward of the conning tower. When the second stick exploded, the U-boat shuddered, and bodies were thrown into the air along with the spray. Shortly afterwards, thirty to forty bodies, some still alive, were seen in the water, suggesting that the crew were on deck in the process of abandoning ship when the last attack was made. Oulton, who was still around, flew over the scene and dropped two rubber dinghies and two Mae Wests. “At that point, I felt very sorry for those poor devils in the water,” he said later. “They had only been doing their duty as they saw it and were as brave as any other combatant.”
When the boat disappeared from view, both E/10 and X/228 left the scene, satisfied that the thoroughly hammered enemy craft had been destroyed. The U-Boat Assessment Committee agreed with them and gave major credit for the kill to Oulton in R/58, who carried out the first two attacks, causing severe damage, and homed in another aircraft. But it also praised the teamwork exhibited by the other participating pilots. In a rare personal expression, the Committee commented: “A triumph of co-operation and a good party in at the death.” Oulton was awarded the DSO and DFC for this and previous actions. Pilot of E/10 Flight Lieutenant Maxwell S. Mainprize and pilot of X/228 Flight Officer William M. French each received the DFC. The U-boat sunk was later identified as the Type VIIC U-563 (Kptlt. Gustav Borchardt), which had sortied from Brest on her eighth war cruise two days before.
While that remarkable series of attacks was taking place, Sunderland “R” of 201 Sqdn. was patrolling Derange in position 45°38’N, 13°04’W when, at 1711, a surfaced U-boat was sighted visually, bearing 240°T, distant 8 miles, on an outbound course of 250° at 5–6 knots. Pilot Flight Lieutenant Douglas M. Gall immediately headed straight downhill from 5,000 feet at 150 knots. It was his crew’s first-ever U-boat sighting after many fruitless and boring 15-hour patrols, and he was not going to let this chance go by if he could help it. The only thought that deterred him was that this submarine might be “one of ours.” When he saw light pulses from the boat he feared that they might be Aldis lamp flashes of the recognition Letter of the Day, but a Scottish gunner put his mind at ease: “He’s no’ flashin,’ skipper, he’s firin’.”
Gall made his run in up the U-boat’s track at 50 feet off the deck. In the last seconds of the approach, when it appeared that his four-D/C drop might miss the U-boat to starboard, the U-boat suddenly made a turn to starboard directly into the stick(!). When the explosion plumes subsided, the U-boat was observed to proceed on course for approximately half a minute, then to sink by the stern at a steep angle into the dark malls below.
After making a circuit to port, Gall and his crew saw the surface shimmer from two heavy underwater explosions. One or two minutes later, they watched the sea “effervesce” over an area 200 to 300 feet in diameter and become pale blue and brown in color. A large oil patch appeared and eventually extended a half-mile in diameter. At 1753, Gall’s aircraft resumed patrol with the crew cheering loudly at their triumph. But, as Gall said later, his own feelings were the same as those of Oulton after U-563—“the poor devils!” For the action he received the DFC. The boat was later identified as U-440 (Oblt.z.S. Werner Schwaff), which had sortied from St.-Nazaire on the 26th, bound for what she hoped would be her fifth war cruise.
No. 19 Group, and units of No. 15 Group attached to it, did not accomplish May’s six sinkings and seven damaged U-boats in the Bay transit area without losses of their own, nineteen aircraft in daytime and two at night. Twenty-eight percent (6) of the losses were to enemy aircraft, mainly JU88C6 heavy fighters based on the Biscay coast at Kerlin Bastard near Lorient and Bordeaux Mérignac. Also active, and possibly responsible for daylight losses to “unknown causes,” were four-engine Focke Wulf 200s at Bordeaux and shorter-ranged FW190s at Brest. Another 28 percent of aircraft (6) were lost on takeoff or landing crashes. Twenty-four percent (5) were shot down by U-boat flak. And twenty-one percent (4), including two L/L Wellingtons at night, were lost to unknown causes. (Aircraft occasionally lost engines; the twin-engine Wellington VIII could not maintain altitude on one engine. Some aircraft, as earlier noted, flew into destructive weather systems; some, through navigational error, went down from fuel exhaustion; still others, when close to the sea, hooked a wing on a wave and cartwheeled in.)
The human casualties in the Bay during May were ninety-four crewmen killed, seven missing, and six taken prisoner (from the shot-down Whitley “N” of 10 Sqdn. O.T.U. on 30 May). An additional fifty-two men, two with injuries, were rescued by their countrymen. The number of airmen both killed and missing (101) compares with the number of U-boat crew members killed on six boats, which was 264, figured on the typical Type VIIC crew list of forty-four. The number of U-boat crewmen lost or wounded on damaged boats is not known. The total hours of RAF and RAAF flight time from liftoff to landing required to destroy six boats and damage seven was 6,181 in daytime and 1,314 at night: that is, 1249 flight hours per U-boat sunk, or 576 hours per boat sunk or damaged.
On the strength of the numbers given above it is difficult to assess whether BdU’s policy of maximum submergence at night saved more U-boats than would have been saved had most submerged hours been observed by day, as was the practice prior to May. Certainly in favor of the May policy were the five known aircraft shot down in daylight, actions that not only saved the U-boats involved but also inflicted material and human losses on the enemy, which would not have been likely if attempted at night. Without real numbers for comparison the question remains speculative, but the historical judgment continues to be that the Dönitz/Godt policy was mistaken.
Although No. 19 Group was never able to put in the air the full requirement of 260 aircraft specified in both the Stark and Admiralty plans, proportionately, for the number of assets that could be made available, and taking into account the spanner thrown into the plans by BdU’s surprise nighttime submergence policy, it was thought by both the Air Ministry and AOC-in-C Coastal Command Air Marshal Slessor that Operation Derange had matched the predictions put forth in Raushenbush’s paper. The 103 sightings and 68 attacks in the Bay in May conformed to the numbers crunched in Raushenbush’s “slide rule strategy.”
Twice Slessor went on record to that effect, first on 12 May in the 18th Meeting of the A.U. Committee, when he stated: “An analysis over the past four weeks of operations in the Bay of Biscay showed that the number of sightings and attacks accorded with the previous estimates that had been submitted to the Committee.” And on 23 May, in a “Comparison of Actual and Estimated Results,” Slessor reported to the A.U. Committee that his general conclusion, based on a sufficiently long period of operations to permit such a conclusion, was, in the case of Derange, “that the difference between theory and fact is very small—in fact the two can never be expected to approximate more closely in war.” (Nor could there ever be a more candid concession to strategy by slide rule.) “The analysis of those operations, therefore, can be taken as bearing out the calculations used in A.U. (43) 84 and 86.”
The latter document cited (86) was the Rauschenbush paper (Stark Plan). The former (84), cannily, was Slessor’s own “Value of the Bay of Biscay Patrols” Paper, in which he had consigned the Bay offensive to the status of “a residuary legatee.” If anyone knew, he did, that while there had been 103 sightings and 68 attacks in the Bay during May, there had been 110 sightings and 67 attacks elsewhere in the Atlantic during the same period; and that, while six U-boats had been sunk and seven others damaged in the Bay, during May there had been nine sunk and four damaged by Coastal aircraft giving cover to threatened convoys. Slessor had loyally come on board the Raushenbush strategy. But he had been vindicated, too.
Of such judgments it is not thought that Stephen Raushenbush had any direct knowledge. After Enclose I, learning that his permanent position at the Department of the Interior was in jeopardy, he resigned from the Navy and returned to Washington to reclaim it—and to enter an obscurity from which only now he has been delivered. Virtually unknown for the brief but impressive role he played in the making of Black May, he died in 1991 at the age of ninety-five in Sarasota, Florida. Evan James Williams, it was earlier noted, died in 1945. Patrick Maynard Stuart Blackett, Baron Blackett, of Chelsea, died in 1974.