Black May (54 page)

In the Admiralty’s Naval Staff wash-up on this convoy it was decided that the successful passage was owed to four factors: (1) the heavy air support during the time that U-boats were in contact; (2) the timely arrival of the First Support Group on the 19th; (3) the accurate appreciation of the situation throughout by the Senior Officer escorts; and (4) the successful evasive steering of the convoy both away from known U-boat positions and immediately before dawn each day while in contact in order to hook or slice submerged boats into the rough.
⁶⁷
What might well have been added was: (5) the efficient use by
Duncan, Tay, Sennen,
and
Zamalek
of HF/DF, which enabled Gretton at considerable distances to vector his air and sea assets economically to fixed targets. Said Gretton in his Comments of Senior Officer, Close Escort: “Directing an escort without reliable HF/DF information is like entering a ring blindfolded.”
⁶⁸

In the retrospect of a half-century and more, SC.13o’s was one of the more significant convoy passages of May, since it demonstrated dramatically both how effective Allied escort operations had become and how far the U-boat fortunes, so promising at the beginning of the month, had declined. It is striking also how few of the
Donau
and
Oder
boats dared to run the Allied gantlet. Were their Commanders practicing a caution approaching timidity, or were they simply denied every chance to advance? We shall probably never know, since the few survivors among them today would not be able to speak for all or even most.
⁶⁹
What is clear is that an already grim exchange rate worsened further, falling from one-to-one in Convoy ONS.7 to a negative balance of three U-boats (counting U-273 but not U-3
81)
lost for zero merchant ships sunk in SC.130. The bar graphs at BdU could be hung with black crepe for the dire tale they told. The mighty U-Bootwaffe,
once the scourge of the oceans, only twenty-five days after its strongest-ever month’s start, wallowed at worsening discount.
Fortuna secunda, denique adversa, uti
⁷⁰

On 21, 22, and 23 May the Allies pulled off what might be called a trifecta. On those three days, successively, a British submarine sank a U-boat; an American escort carrier (CVE), U.S.S.
Bogue,
got its first kill; and a U-boat was sunk by the first rocket used successfully in naval warfare. Although it may not seem obvious that one side’s submarine might sink another side’s submarine, since they were two scorpions that rarely got into the same bottle, it was hardly unknown for that to happen: since the war’s start eight U-boats had been sunk by British submarines, the most recent being U
-644
(Oblt.z.S. Kurt Jensen), sunk by H.M.S. (submarine)
Tuna
on 7 April in the North Sea northwest of Narvik. In fact, on the 18th of the same month, the German boat U
-123
(Oblt.z.S. Horst von Schroeter) sank a British submarine, H.M.S.
P.
615, south of Freetown. On 21 May, H.M.S.
Sickle
was patrolling in the Mediterranean off the southern coast of France when, at 1456, she sighted a Type VIIC boat leaving the port of Toulon on a test run.
Sickle
closed the range to 2,600 yards and, at 1510.29, launched two Mark VIII torpedoes 2½ seconds apart set to depths of 8 and 10 feet. One torpedo struck the U-boat about 30 feet abaft the conning tower, sending up a towering detonation column of water and smoke. The boat settled by the stern and the crew were seen jumping into the sea. The bows of the boat stood up at an angle of 50° and then slid under at 1512.20.
Sickle
made no attempt to pick up survivors, since it would have “unnecessarily hazarded” the submarine. The victim was
U-303
(Kptlt. Karl-Franz Heine). Twenty of the forty-four-man crew were lost.
⁷¹

On 20 May the U.S. Navy created the Tenth Fleet, a paper organization with no warships of its own, which would allow Admiral King, by that date heavily committed to ASW, to bring together all anti-submarine ships, aircraft, weapons, radar and HF/DF, Intelligence, operations research, communications, convoy routing, and tactical attack doctrine and training under one overall command—his own. While a Tenth Fleet chief of staff, Rear Admiral Francis S. “Frog” Low, handled day-by-day administrative duties, and Admiral Royal E. Ingersoll,
Commander in Chief Atlantic Fleet (CINCLANT), directed operations at sea, King supervised Tenth Fleet and Low in much the same way that his German counterpart, Dönitz, superintended BdU and Godt. On the date of Tenth Fleet’s epiphany—long-awaited, it should be said, by critics, particularly in the Army and USAAF, who thought that the Naval service’s approach to the U-boat threat had been too random, reactive, and unstructured
⁷²
—the Tenth Fleet’s prize Atlantic weapons platform was in mid-Atlantic steaming toward a pack of twelve wolves. This was U.S.S.
Bogue,
the first American-built escort carrier to fight U-boats under the United States flag.

Converted from a C-3 merchant hull at Tacoma, Washington, named after Bogue Sound in North Carolina, launched on 15 January 1942, and commissioned by Captain Giles E. Short on 26 September of that year,
Bogue
was classified an ACV for Auxiliary Aircraft Carrier (until July 1943, when the classification would be changed to CVE for Escort Carrier). In service she would be designated CVE-9. Popularly, she would be known as a “Jeep” carrier.
Bogue’
s flight deck was 442 feet 3 inches long. A narrow “island” (five feet wide, twenty-five long, fifteen high) stood on the starboard side. The vessel’s steam turbines and single screw produced a maximum speed in open water of 17.75 knots. Her normal crew complement was 890, but it quickly grew to a crowded 97 officers and 921 men.
⁷³
In November 1942, at San Diego,
Bogue
embarked her aircraft: nine Grumman TBF—1 Avenger torpedo-bombers and twelve Grumman F4F4 Wildcat fighters. Together they formed the Escort Scouting Squadron Nine (VGS-9), redesignated Composite Squadron Nine (CV—9) on 1 March 1943. Commanding Officer was Lieut.-Comdr. William M. Drane, U.S.N.

In many ways, though not all, the Avenger represented an advance over the
Archers
and
Biters
Fairey Swordfish. Where the latter, a fabric-covered biplane, had a weight of 9,250 lbs., a maximum speed of 139 mph, and a range of 546 miles, the aluminum monoplane Avenger had a weight of 15,905 lbs., a top speed of 270 mph, and a range of 1,215 miles. On two counts, however, they were similar: the Swordfish had a crew of two or three and the Avenger a crew of three (pilot, radioman, and gunner); and both had a bomb load capacity of 1,600 lbs.

The Avenger’s speed enabled it to deliver an attack before the
targeted U-boat could submerge, while exposing the aircraft to flak for the shortest possible time. Again, the Avenger’s endurance permitted it to remain on patrol or over a target for an effective period of time. The preferred type of attack, worked out in theory and practice, was a long power glide at maximum speed out of cloud or cloud bases, followed in the final stage by a pushed-over 20° dive with wheels lowered to reduce speed for the D/C drop. While the D/C depth was set to 25 feet in keeping with the doctrine learned at the Fleet Air Arm Anti-Subma-rine School, Ballykelly, Northern Ireland, which all of
Bogue
’s TBF-I pilots would attend, Squadron Nine chose to reduce the 100-foot spacing recommended there to 75 feet because of the speed of their aircraft.

The purpose of the Wildcats was primarily to provide defense against air attacks, not likely in midocean but possible when operating near the U.K., and secondarily to strafe surfaced U-boats in coordinated attacks with the TBF-Is. In the latter case Lt.-Cmdr. Drane was insistent that the Wildcats restrain themselves by not engaging in highspeed maneuvers that condensed vapor in humid air and gave away the attack, and by not dashing about madly without orders from the accompanying Avenger and thus compromising an attack by driving a U-boat down prematurely. Ideally, a Wildcat should be available on call to strafe the U-boat from three to five seconds before the D/Cs were dropped. The operational endurance of each aircraft type was, for the TBF-16 hours at 125 knots, for the F4F4 3.5 to 4 hours at 125 knots. Both types could be launched by the flight deck catapult without the carrier having to turn into the wind, a wind component of only 16½ knots along the track being required by a fully loaded TBF—1, and a component of only 6 knots being required by an F4F4. Without the catapult, wind velocity over the deck necessary to fly off aircraft was 31 and 24 knots, respectively.
⁷⁴

Bogue
was named the centerpiece of a pioneer aggressive USN sea force called the “Hunter-Killer Group.” Her mission, not unlike that of
Archer
and
Biter
, was to hunt down U-boats in the vicinity of convoys and destroy them. It was thought at first by Ingersoll that
Bogue
s best use was on the Central Atlantic routes to and from Gibraltar, where generally good weather conditions favored aircraft launches and
recoveries, but as it happened,
Bogue
found herself from the outset in the thick weather and heaving seas of the North Atlantic lanes. On 6 March 1943, out of Argentia, Newfoundland, accompanied by two “flush-deck” destroyer escorts, U.S.S.
Belknap
and
George E. Badger,
she joined the U.K.-bound Convoy HX.228. Four days later, Avenger pilot Ensign Alexander C. “Goose” McAuslan, U.S.N.R., sighted a U-boat and dove to attack it. Both D/Cs he was carrying hung up in their racks. (In pitching seas the squadron was fitting only two D/Cs in the TBF-
IS
to assist takeoff.) The U-boat initiated a dive while McAuslan swung around for a second run. Again his D/Cs failed to release.
Bogue
was ordered to return to Argentia; on the way, TBF-1 pilot Lt. H. S. “Stinky” Roberts, U.S.N.R., mistook a gam of porpoises for a U-boat and had yet another bomb rack failure, to the very good fortune of the sea mammals. Something would have to be done about the bomb hangups, and it was.

On 20 March,
Bogue
began a second partial crossing as air escort to SC.123, but rough seas and wet gray curtains caused her aircraft to stand useless in their lashings for most of the voyage. On the 26th she began a return to Argentia, arriving there four days later. On 25 April she joined Convoy, HX.235, which was routed to the southward through better weather. This time, with the addition of three more flush-deck destroyers, U.S.S.
Greene, Lea,
and
Osmond Ingram,
the carrier had a five-escort screen. The entire support force was designated Task Group 92.3. Their passage was uneventful until the afternoon of the 28th, when Lt. Roger “Stomp” Santee, U.S.N.R., in an Avenger, caught a fully surfaced U-boat about 50 miles distant from the convoy and attacked it with two D/Cs that released well enough but ricocheted off the surface, owing to too much speed on the dive, and went under to explode too far from the target.

Two days later, TG 92.3 was detached to make for Belfast, where, during the following two weeks,
Bogue’
s officers passed through the Anti-Submarine School at Ballykelly, a British HF/DF set was installed in the carrier’s island (see chapter 2), and VC-9's TBF-I quota was increased from nine to twelve, while the F4F4 fighter complement was reduced from twelve to six.
⁷⁵
Interestingly, in his comments on the
new aircraft composition, Captain Short suggested that four slower type-aircraft, such as the Swordfish, be substituted for three TBF-is: “The Swordfish, for instance, can be operated in weather which precludes the landing and take-off (except by catapult) of the TBF. They could be used for night operations and rough water work when the employment of the heavy and faster TBF would be unduly hazardous in this class of vessel. Further, a slow aircraft at night would prove more effective in spotting submarines than a fast one.”
⁷⁶
The suggestion was not followed.

Bogue
departed Belfast Lough at 1837 on 15 May. Three and a half hours later she rendezvoused with her surface escorts, minus
Lea,
to form the Sixth Escort Group, and proceeded to Iceland. From there, on the 18th, the Group, taking with it the freighter S.S.
Toltec,
intersected the route of the westbound convoy ON.184, which it was to accompany in support of the close screen. Destroyer
Lea
overtook the remainder of the Group on the 18th, and at dawn the next day,
Bogue
and her four-stackers took assigned convoy stations,
Bogue
in the Commodore’s column astern of the escort tanker. Heavy weather made flying impossible until the 21st when, coincidentally, ON.184 stumbled on a pack of U-boats that had been assembled not to meet it, but another, eastbound, convoy, HX.239 (escorted by
Archer),
crossing 30 miles to the south, which had been betrayed by Naval Cipher No. 3. Again, as in the case of Convoy SC.130 in the middle of the month, B-Dienst had decrypted HX.239's position, course, and speed, and BdU had formed a patrol line of twenty-one boats named
Mosel
(after the river) across it.
⁷⁷

Subsequent decryptions by B-Dienst enabled BdU to know the convoy’s estimated positions for the 20th, 21st, and 22nd.
⁷⁸
Since these positions were farther to the south than BdU had anticipated, twelve
Mosel
boats were instructed to proceed southeastward to make contact. Boats of the
Donau
group withdrawing from SC.130 were also vectored to intercept at AK 97 (51°25'N, 30°15'W). None of these orders was decrypted by the Allies before 22 May, and some signals relating to the dispositions of southern
Mosel
were not read until 3 June.
⁷⁹
On the 20th, B-Dienst intercepted a signal giving the position of convoy
ON
.184 as 51°01'N, 33°5O’W.
⁸⁰
Ironically, it was the carrier escort of
ON.
184 that the southern
Mosel
boats would encounter first as the two convoys passed in opposite directions some 520 miles southeast of Cape Farewell.