Black May

by Michael Gannon

  Waddington testified that “At least in the sphere of my experience, I have rarely met such critical generosity of mind as was shown to us civilian ‘intruders.'” At no time, it appears, was there the slightest concern on the part of Joubert or Slessor that the “suck it and see” scientists sought an unwarranted prominence for themselves or ever considered themselves as anything other than members of a team.30

  In citing the contributions to Coastal of non-RAF personnel, special mention should be made of the senior Naval Liaison Officer, Commander, later Captain, D. V. Peyton Ward, R.N., who was the very embodiment of the close and fruitful relationship that existed between Coastal and the Admiralty. An invalided-out submariner, “P.W.,” as he was affectionately known at Northwood, volunteered for tasks not normally required of his position, and after Joubert’s arrival he took it upon himself to interview all returning aircrews who had sighted and/or sunk a U-boat. By writing up and analyzing each such incident, he greatly enlarged the attack data available to O.R.S. A navy-blue in the midst of RAF slate-blue, he represented Coastal on the important interservice U-Boat Assessment Committee, which judged the success of surface and air attacks. After the war, he wrote the official four-volume history of air operations in the maritime war.31 All the while O.R.S. and P.W. were bending their minds, the aircrews practiced their own difficult art of air search, hundreds of miles out over the Atlantic’s gray flannel, noisily patrolling 1,000 to 5,000 feet off the deck, in every kind of weather, dirty and cold, rarely if ever in their entire flight careers sighting a single U-boat to reward them for their protracted and boring hours. Said one crewman:

  It is difficult to describe the intense boredom of the sorties we undertook: hour after hour after hour with nothing to look at but sea. I am sure that when they found U-boats many crews pressed home their attacks regardless of what was being thrown at them, merely because it was a welcome relief from the boredom.32

  And many crews would be shot down, in distant positions where no assistance was near or possible. And many other crews were lost to the sea not through enemy action, but through engine failure, adverse weather, navigational error, and fuel depletion.

  Coastal Command’s motto was: “Constant Endeavor.”

  The Bay of Biscay is a roughly triangular body of water bordering the Atlantic that is formed on the north by the Brittany peninsula of France, where it does an arabesque toward Land’s End on England’s Cornwall coast, and on the south by the northern provinces of Spain. About 86,000 square miles (223,000 square kilometers) in size, and 15,525 feet (4,735 meters) deep at its center, it was the body of water traversed by U-boats operating out of bases at the western French ports of Brest, Lorient, St.-Nazaire, La Pallice, and Bordeaux. Normally, outbound and inbound boats transited through a zone, or “choke point,” about 300 miles north to south and 200 miles east to west. Here, more than at any other sea position, U-boats could be found in high concentration: traffic ranged from forty-five boats per month in June 1942 to a figure that, in early 1943, passed 100 (expected to increase to 150 by spring). The Strait of Gibraltar was another choke point, but far fewer boats attempted its passage; and the northern route from Germany around the north of Scotland was another transit area, but one that was used almost exclusively by new boats coming into Atlantic service. If one wanted to find a large number of U-boats bunched up in any one place, it would be in the transit zone of the Bay of Biscay.33 In March 1943, the Admiralty said of the enemy:

  Apart from modifying his tactics, or disengaging from an attack, he can withdraw altogether from any given convoy area as he had done to a large extent in the areas off the American coast. He cannot withdraw from the Bay.34

  Whether U-boats were bound to and from the midocean transatlantic convoy lanes, where the most intensive pack battles were fought, or to and from what the British called the Outer Seas—Freetown, Cape Town, the Indian Ocean, the Atlantic Narrows, Brazil, the Caribbean, and the North American seaboard—the swept channels of the Biscay minefields were the narrow funnel through which every boat had to pass. To an adversary with marksman instincts, the Bay presented an irresistible bull’s-eye.

  From the date he assumed command at Northwood in 1941, Air Chief Marshal Joubert cast a malevolent glare in that direction. Like many at Coastal before him, he could not understand why Bomber Command with its heavy bombardment squadrons had not destroyed the steel and concrete U-boat bunkers while they were still under construction and vulnerable. As a matter of fact, Bomber Command did attempt to disrupt construction, making twenty nighttime raids on the Lorient base in 1940, sixteen in 1941, and twelve in early 1942. The U.S. Eighth Air Force made ten daylight raids on St.-Nazaire between November 1942 and June 1943. Other raids were mounted against Brest. All such raids were ineffectual, owing to poor bombing accuracy and to intense anti-aircraft fire that caused heavy bomber losses. The only result on the ground was the flattening of the towns where the bases were situated. Of Lorient and St.-Nazaire, Admiral Donitz said that not a cat or a dog survived. Left with the problem of nearly completed bomb shelters, Joubert decided that since Coastal Command was envisioned to be an offensive instrument and the hunter role suited his nature, he would direct as much of its power as he could spare from convoy escort to that of offensive patrol against U-boats transiting the Bay. In making that decision, he entered a debate that would never be completely resolved, either in Coastal or the Admiralty: whether ‘tis nobler to defend convoys and so win the Atlantic by seeing merchantmen to safe and timely arrivals at their destinations, or to take up arms against a sea of U-boats, and by hunting, kill them?

  What came to be called the First Bay Offensive, launched by Joubert in the summer of 1941, was a daytime operation flown by Sunderlands, Wellingtons, Whitleys, Hudsons, and Catalinas, all of them equipped with 1.5-meter wavelength ASV Mark II radar. It yielded very disappointing results. O.R.S. analysts discovered that 60 percent of the U-boats sighted the approaching aircraft before being spotted themselves, and thus were able to dive out of harm’s way. As the campaign wore on into autumn, it became clear that transiting U-boat commanders, alerted to the increased presence of aircraft in the Bay, were charging their batteries on the surface at night and traveling as much as possible submerged during the day. Sightings of boats decreased accordingly, and the record shows that the year ended without a single U-boat kill by aircraft in the Bay.35

  What was needed, argued Professor Blackett of O.R.S., who chaired a specially organized Night Attack Sub-Committee under the ASW Committee on Aircraft Attacks in the Admiralty, was an effective means of delivering attacks during darkness when the U-boats were on the surface charging. And that meant an illuminant that could display to the pilot’s eye targets detected first by radar. In early 1942 combat experiments were run using 4-inch flares towed by radar-equipped Whitleys, but these proved unsuccessful. Another, more promising illuminant was waiting in the wings.

  When in September 1940 the then AOC-in-C Air Chief Marshal Bowhill sent around a memorandum asking officers and airmen to submit ideas for improvement of ASW operations, he received back a detailed proposal for an airborne searchlight for use in night attacks on surfaced U-boats. It came from a nontechnical source, a World War I pilot who had flown ASW patrols over the Mediterranean in that conflict, named Squadron Leader Humphrey de Verde “Sammy” Leigh, now serving as Assistant Personnel Officer in headquarters administration. Leigh proposed that the so-called DWI Wellingtons, which had earlier, but no longer, been used to explode magnetic mines from the air by generating a powerful electrical charge, be refitted with a belly-installed retractable carbon arc lamp. The DWIs recommended themselves for this use because they were already equipped with auxiliary engines and either 35-or 90-kilowatt generators.

  Bowhill was so impressed by the idea that he relieved Leigh of his desk duties and set him to work full-time on the project. There were numerous obstacles to overcome, starting with the technicians at RAE, Farnborough, who argued the case for towed flares as prefe
rable to the searchlight scheme. The nontechnician Leigh pressed on regardless, and ingeniously solved every problem that he encountered, among them ventilation of the carbon arc fumes, steering control of the lamp’s beam in azimuth and elevation, prevention of back glare, or “dazzle,” and reduction of weight. In March 1941 the Vickers plant at Brook-lands completed a prototype installation employing a naval 24-inch (61 cm) narrow-beam searchlight, giving a maximum 50 million candles without a spreading lens, powered by seven 12-volt 40-ampere-hour type D accumulators (storage batteries); and on the night of 4 May, with Leigh himself operating the light controls in the nose, the first Leigh Light Wellington repeatedly detected, illuminated, and “attacked” the British submarine H—31 off Northern Ireland. Bowhill was no less gratified at this success than Leigh, but only one month later, when Bowhill was relieved by Joubert, the whole project was canceled and Leigh found himself reassigned to a desk.

  It happened that Joubert had been associated with the development of a competing airborne light system called the Helmore Light, after an RAF Group Captain, which had been designed for illuminating enemy bombers at night, and the new AOC-in-C thought it should be used against U-boats as well. But the Helmore Light was quickly shown to be unsuitable for Coastal work: its massive array of accumulators occupied the entire bomb bay; the light could not be steered, or aimed, except by moving the entire aircraft; and the brightness of the light, which was mounted in the nose, dazzled both the operator and the pilot. “After some two months I found, as I do not mind admitting,” Joubert wrote later, “that I had made a mistake.”36 Leigh cleaned out his desk a second time and returned to the hangar.

  Months of redesign, flight testing, crew training, and what Peyton Ward called “difficult to explain” administrative delays followed, until finally, at the beginning of June 1942, a “penny packet” of five Leigh Light (L/L) Wellingtons of No. 172 Squadron entered operational service in the Bay. The first L/L-assisted attack was made on 4 June against the Italian submarine Luigi Torelli (Tenente di Vascello [Lt.-Cmdr.] Augusto Migliorini), resulting in severe damage.37 The attack was made by Squadron Leader Jeaff Greswell, flying Wellington “F” of 172 Squadron. During June and July the Wellingtons, showing what the surprised and helpless Germans came to call das verdammte Licht— “that damn light”—made altogether eleven sightings and six attacks, resulting in one kill—the Type IXC U-502 (Kptlt. Jürgen von Rosenstiel) en route home from the Caribbean, sunk by Wellington VIII “H” flown by Pilot Officer Wiley Howell, an American serving with the RAF—and two boats damaged.

  Before the Wellingtons could improve on that record, Admiral Donitz ordered his boats in the Bay: “Because the danger of attacks without warning from radar-equipped aircraft is [now] greater by night than by day, in future U-boats are to surface by day…. ”38 In a month and a half’s time the Leigh Light had taken the night away from U-boats in the Bay, but that, it turned out, would be for now their major contribution. The air war in the Bay returned to daylight hours, and with slightly better returns than before, as between mid-July and the end of September, conventionally equipped aircraft made over seventy sightings and sank three additional boats.

  Still, the great opportunity that the Bay presented eluded Coastal’s grasp. The ratio of kills to daytime sightings remained disappointingly low throughout the remainder of 1942 and well into the new year. Whereas Coastal had expected that with increased time given to practice attacks, with, at last, 25-foot depth pistols, and with Torpex fillings, the percentage of lethal attacks would rise to 20 percent, it hovered instead at 6 percent. The lethality problem prevailed everywhere in waters that the U-boats infested, even where attacks were made from unseen cloud approaches on Class A targets, that is, those in which the U-boat was on the surface or had been submerged fewer than 15 seconds. Coastal was divided on the question of where blame should be placed: on poor weapons or on poor aim? Rear gunner reports and photographs suggested that the 250-pound Torpex D/C did not seem to injure boats even when perfect straddles were achieved. The O.R.S., however, defended the weapon, and, after intense study, determined that, photographs seemingly to the contrary, the problem was aiming, which could be corrected by more and better training.

  In support of this conclusion the O.R.S. produced evidence that three outstanding squadrons, No. 120 (6 kills, 10 damaged), No. 202 (4 kills, 5 damaged), and No. 500 (4 kills, 9 damaged) also had solid records in practice bombing. It pointed as well to certain individual pilots, such as Squadron Leader Terence M. Bulloch, of No. 120 Squadron, with three boats sunk and three damaged, and Flying Officer M. A. “Mike” Ensor of No. 500, with one sunk and three damaged. In each case, the former in a Liberator, the latter in a Hudson, painstaking practice had translated into successful performance in combat.39 There was nothing wrong with the weapon. O.R.S.'s findings set in train intensive drills in marksmanship.

  Another problem that the daylight bombers had to face was an increase in opposition from the Luftwaffe, which in the summer and fall of 1942 attempted to interdict Coastal patrols in the Bay, employing Focke-Wulf 190s, Heinkel 115s, Junkers 88s, Messerschmitt 210s, and Arado 196s. Some aircraft and crew casualties resulted, but No. 235 Beaufighter Squadron at Chivenor in Devon successfully fought the attackers off, and the enemy air effort died away.

  The nighttime bombers, which continued busy in the Bay Offensive, had problems of their own. The first was the French tunny (tuna) fleet, which followed the shoals of tunny into the middle Bay where most of the Leigh Light aircraft were operating. Numerous A.S.V. blips, when illuminated, turned out to be tunny craft. Their radar signature was indistinguishable from that of a U-boat. Use of the searchlight in these cases not only caused a 25 percent waste of effort and ran down the electrical power in the batteries, it gave fair warning to U-boats nearby that an L/L Wellington was in the area. In August the problem was so severe that L/L missions were considered futile and Coastal attempted to warn off the fishing craft by BBC broadcasts, leaflets, and threats to shoot, but nothing worked and the interference remained intractable until the end of the tunny season in October.

  In the meantime the L/L flights, indeed all flights, were confronted by a far more serious problem. Admiral Dönitz’s technical staff had concluded, correctly, that the illuminated attacks in the Bay had been made possible by airborne metric radar. Helped by an A.S.V. Mark II set captured in Tunisia, BdU technicians developed a radar receiver (Type R.600) that could detect the presence of 1.5-meter pulses and give a U-boat time to dive out of danger. In fact, it produced a warning signal at a greater range than that at which an aircraft could acquire the blip (plus or minus 10 miles). Manufactured by the Paris firm Metox (also later by Grandin), the equipment was put to sea in August on three boats, U—214, U—107, and U—69. Except for problems encountered with the antenna, which was affixed to a crude wooden crosspiece (Biskayakreuz, the “Biscay cross,” as it came to be called) that had to be carried up and down the tower ladder when surfacing and diving, causing troublesome delays, the three boats reported favorably on the device’s effectiveness. Donitz then ordered the equipment fitted to every boat in the fleet, a process that was nearly complete by the end of the year. This logical German countermeasure enabled the boats to resume surfacing by night.

  A dramatic falloff in Coastal sightings, both day and night, together with intelligence drawn by Winn and Beesly from naval Enigma, gave Northwood a strong clue to what had happened. The value of the Bay campaign in these circumstances came under strong questioning, and AOC-in-C Joubert pressed London hard for 10-centimeter equipment with which to defeat the German Search Receiver (G.S.R.). But the first squadron to be so equipped did not become operational until the following March. In the meantime, Coastal relied on the only expedient available: flooding. In this tactic all the aircraft over the Bay except the L/L Wellingtons, which, it was hoped, might catch a U-boat off its guard, were to use their A.S.V. continuously. The expectation was that with the G.S.R. alarm ringing without stop, U-boats woul
d not know when they were being targeted—an alarm that rang all the time was as useless as one that rang not at all—and so might become complacent or careless. But the tactic did not lead to additional sightings and attacks. In fact, during January 1943 a total of 3,136 day hours led to only five sightings, and 827 hours of combined L/L and conventional night patrols produced only three sightings.40 These were a new low record in the Bay.

  During the U-boats’ six-month-long picnic on the North American seaboard, overstretched and weary RN surface escorts had a respite in which to fit new detection gear, practice use of weapons, including, on some ships, the new Hedgehog, and train ranks and ratings. The ratings’ first training experience, and in many cases, their first glimpse of the sea came when newly commissioned escort vessels received their working up at H.M.S. Western Isles in Tobermory harbor on the Isle of Mull off the west coast of Scotland. There the legendary (and quirky) Commodore Gilbert “Puggy” (or “Monkey”) Stephenson took callow “Hostilities Only” landlubbers—1,132 groups in all during the war— and, within two to three weeks’ time, shaped them into disciplined, semiskilled seamen who went directly into convoy escort service.41‘