Payback: How the Royal Navy Hunted Down Hitler’s U-Boats

Payback: How the Royal Navy Hunted Down Hitler’s U-Boats

United States antisubmarine aircraft played an unsung but vital role in this campaign.

The coming of spring brought both milder weather to the North Atlantic and a corresponding increase in Allied convoy activity. As Admiral Dönitz’ submarines sortied out to strike those convoys, so did Air Marshal Slessor’s maritime patrol aircraft scramble to meet them over the Bay of Biscay’s constricted waters. British bombers sank one boat in March, two more during April, and an impressive seven subs caught transiting the bay during the height of operations in May.

King and Arnold’s Fight Over Anti-Submarine Missions

John Slessor derived great pride from the results of his Biscay Offensive, yet the energetic air marshal could not help but wonder how many more U-boats might have been sunk if a few American patrol bomber squadrons had “joined the party.” In June, Slessor traveled to Washington seeking a renewed U.S. commitment to his summer bay campaign, called Operation Musketry. He arrived to witness a long-simmering dispute over control of antisubmarine aircraft finally boil over between the chiefs of the U.S. Navy and Army Air Forces.

General Arnold and the Navy’s commander in chief, Admiral Ernest King, distrusted one another intensely. These two officers created and maintained a poisonous jurisdictional dispute regarding the employment of antisubmarine aircraft, a quarrel that extended back to the dark days following Pearl Harbor. While the U.S. Navy was responsible for protecting American coastal waterways, the only long-range aircraft then available for patrol and convoy escort duties belonged to the USAAF. In March 1942, Arnold agreed to temporarily place Army antisubmarine planes under naval control, at least until the Navy could obtain its own sub hunters. Yet neither Arnold nor King was happy with this arrangement.

The brilliant, irascible King saw Arnold’s increasing involvement in antisubmarine warfare as a grab for power, an attempt by the USAAF to intrude on what was traditionally a Navy mission. Hap Arnold feared the Navy’s interest in obtaining long-range Liberators was merely a cover for involving itself in strategic bombing operations, which he viewed as the Army Air Forces’ purview. For months the two chiefs danced like boxers around this issue, each spitefully rejecting any attempt at improving antisubmarine organization or cooperation.

Opposing tactical doctrines provoked more ill feelings between the two services. Naval policy dictated that patrol planes closely guard merchant convoys, while USAAF guidelines prescribed a more free-ranging, offensive-minded air operation. King scoffed at the Army’s methodology, likening it to searching for a needle in a haystack. He further argued that by sticking to the convoys patrol planes would be more likely to find the U-boats stalking them.

On the other hand, naval district commanders kept USAAF sub-hunting aircraft out operating over their districts long after German U-boats had moved into more productive waters. Flexibility, the greatest advantage of aerial antisubmarine warfare, remained an unexploited asset so long as patrol bombers were prohibited from following their U-boat prey across sea district boundaries.

Negotiating a Resolution to the Conflict

The two sides may never have reached agreement if it were not for a new factory being built in Renton, Washington. In 1942, Boeing Aircraft raised this structure to make the Navy’s PBB-1 Sea Ranger patrol plane. General Arnold thought it would be better served manufacturing B-29 Superfortress bombers for the USAAF, and in exchange for the Renton facility offered the Navy a percentage of future Liberator deliveries. This deal meant the Navy would finally obtain a land-based patrol aircraft while the Army got its Superfortress plant.

The Navy took another step toward accepting full control of the American antisubmarine effort when, on May 10, 1943, Admiral King stood up the Tenth Fleet. It was a paper fleet, wholly without ships or airplanes, but one that represented King’s determination to finally defeat the U-boat peril. Tenth Fleet had as its charter the mission of directing and coordinating all Navy sub-hunter activities worldwide. Curiously, in all of Tenth Fleet’s organizational charts there was no mention of the U.S. Army Air Force’s Antisubmarine Command or its 286 aircraft.

What happened next surprised no one. In a June conference held between Arnold and senior naval officials, an arrangement was made in which the Army would turn over its antisubmarine-equipped B-24s in exchange for an equal number of unmodified Liberators originally allocated to the Navy. Admiral King formalized the pact, writing to Army Chief of Staff General George Marshall on June 14, “The Navy will be prepared to take over all antisubmarine air operations by 1 September 1943.”

26 U-Boats Sunk

This horse trade did not signal an immediate end to USAAF sub-hunter activities. While in Washington, Air Marshal Slessor had persuaded King to release the Army’s 479th Antisubmarine Group for duty over the bay. Four full squadrons of B-24s (the 4th, 6th, 19th, and 22nd A/S) were set to arrive at St. Eval starting in mid-July, while Navy Liberators (PB4Y-1s in naval parlance) would follow along as soon as their crews could be trained.

The American planes deployed just as Operation Musketry reached its operational crescendo. Much had changed since the first USAAF antisubmarine squadrons in England pulled up stakes four months earlier. Admiral Dönitz’ U-boats were now traveling surfaced in groups during daylight hours and slugging it out with Allied bombers thanks to new quad-barrel 20mm antiaircraft cannons hastily mounted to their conning towers. Even more dangerous was the air threat—swarms of Ju-88 heavy fighters prowling the bay in search of unwary patrol planes. German gunfire compounded the normal hazards of weather, fatigue, and mechanical malfunction faced by all Allied sub hunters.

At least the situation at St. Eval had improved. Learning from past mistakes, Colonel Howard Moore’s 479th Group deployed with adequate maintenance, administrative, and logistics support. In August, the Americans moved to RAF Station Dunkeswell, 100 miles down the road in Devonshire. This newly constructed base, dubbed Mudville Heights by the airmen living there, would remain the hub of U.S. antisubmarine activity for the rest of the war.

Operational patrols commenced on July 13, and soon thereafter the 479th scored its first U-boat kill. On July 20, 1st Lt. Charles Gallmeier’s bomber surprised the surfaced U-558, delivering seven depth charges close aboard. The German vessel fought back, though, its well-aimed antiaircraft fire wounding one of Gallmeier’s gunners as well as disabling an engine. A British Halifax then finished off the U-boat, which went down with all 43 hands.

Team tactics resulted in another kill on July 28, when B-24s piloted by Major Stephen McElroy (commanding officer of the 4th A/S Squadron) and 1st Lt. Arthur Hammer joined a British Liberator to fight U-404 in an epic six-hour battle. The hard-fighting submarine damaged all three sub hunters before succumbing to a barrage of 27 depth charges.

The July Massacre ended for USAAF flight crews five days later when Captain Joseph Hamilton’s B-24 helped Canadian pilots sink U-706 about 400 miles west of the St. Nazaire sub pens. On August 2, Dönitz pulled the plug on his disastrous fight-back tactics. Hereafter, German submarines would hug the Spanish coast—where ASV radar proved less effective—surfacing only to recharge their batteries and then only at night. The Kriegsmarine also greatly restricted submarine operations, preserving its fleet while new wonder weapons were fielded—weapons that could change the course of the war.

Coastal Command’s summer Bay Offensive resulted in 26 U-boats killed by air between April and August 1943. Seventeen more had been damaged, significantly degrading the German Navy’s offensive capability. The U-boats were all but defeated, or so said Prime Minister Churchill when he boasted the Kriegsmarine had not sunk a single Allied merchant ship on North Atlantic convoy routes between May 1 and September 15, 1943. No. 19 Group contributed to this victory by whittling away at the Biscayan “trunk” with aggressive, coordinated attacks on enemy submarines.

Ju-88s Strike Back

Sub-hunter aircraft continued to prowl the bay throughout August and September, but by then Dönitz’s remaining U-boats rarely ventured from their pens. Instead, patrol bomber crews faced increasing numbers of Luftwaffe heavy fighters—cannon-armed Ju-88s operating in packs. The USAAF’s first clash with them occurred on July 26, when a Liberator commanded by Lieutenant S.M. Grider encountered nine fighters over the bay. Thinking quickly, Grider escaped undamaged by ducking into some low-hanging clouds.

The Americans’ luck would not last. On August 8, marauding Ju-88s shot down Captain R.L. Thomas’ bomber, killing all aboard. Ten days later they pounced on another B-24, this one with the luckless Grider aboard as check pilot. Grider and his aircraft commander, Lieutenant Charles Moore, managed to successfully ditch their stricken plane, no simple task given the Liberator’s propensity for breaking apart upon hitting the water. Six survivors were rescued by a British warship after spending four days bobbing around the bay on life rafts.

Altogether, the 479th A/S Group lost four B-24s to enemy fighters during 16 recorded air-to-air encounters. American gunners claimed five German warplanes in return, demonstrating that these battles were not always one sided. Yet the USAAF’s ungainly patrol bombers made excellent targets for prowling Ju-88s despite Coastal Command’s efforts to provide escort coverage.

The Navy Takes Over For the USAAF