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Introduction

In 1942 the Allied powers faced the most serious

challenge to their control of the seas encountered in the

Second World War: the menace of the U-boat. Fast, wellarmed, and long-ranged, Hitler's submarines attacked

shipping throughout the North Atlantic, often within sight of

America's coastal towns and cities.

Eventually, the combination of intelligence, land and seabased air power, and surface vessel operations from both

North American and British bases ended this threat, making

possible the Allied build-up for the invasion of Europe in

1944.

This booklet, by A. Timothy Warnock of the Air Force

Historical Research Agency, is one of a series tracing selected

Army Air Forces activities in the Second World War. It

describes the Army Air Forces' contribution to the Battle of

the Atlantic from the American Theater. A subsequent booklet

will examine the campaign in the eastern Atlantic and the

Mediterranean.

Flying radar-equipped long-range patrol planes, AAF

airmen demonstrated the value of land-based air power

against naval threats. This success has been reaffirmed

consistently since the Second World War, from Vietnam and

crises such as the Mayaguez incident to operations in Desert

Shield and Desert Storm. The Harpoon-armed B-52s

of our present-day global Air Force are the heirs of a seacontrol tradition dating to the AAF's A-29s and B-24s of the

Second World War.

Richard P. Hallion

Air Force Historian

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The Battle Against the U-Boat

in the American Theater

December 7, 1941-September 2, 1945

The political settlement ending World War I left a bitter legacy

that poisoned international relations and led within twenty years to an

even more devastating war. By the 1930s, totalitarian regimes in

central Europe and Japan threatened their neighbors. In the Far East,

Japan occupied Manchuria in 1931 and 1932, a first step in seeking the

domination of China over the next dozen years. In Europe, Adolf Hitler

assumed dictatorial power in Germany in 1933 and rebuilt that

country's military forces. Between March 1938 and September 1939,

Hitler annexed Austria, dismembered Czechoslovakia, and, with the

acquiescence of the Soviet Union, invaded Poland on September 1,

1939. Having guaranteed the integrity of Poland's borders, Great

Britain and France declared war against Germany on September 3.

Between February and June 1940, Germany overran Denmark,

Norway, the Netherlands, Belgium, and France, leaving only Great

Britain to oppose Hitler's ambitions in western Europe.

As the world edged closer to another major conflict, the United

States maintained a strong isolationist position in the international

community. By 1939, however, President Franklin D. Roosevelt

realized that the United States could not remain neutral indefinitely as

the Axis Powers-Germany, Italy, and Japan-gradually escalated their

aggression and violence. While the United States remained unwilling to

wage war, President Roosevelt gave China in the Far East and Great

Britain in Europe all the encouragement and support possible.

While providing aid to China and Great Britain, the United States

began to build its war industry and rearm, thus preparing for entry into

the war. President Roosevelt sought to make the United States an

"arsenal for democracy." The Allies obtained armaments and supplies

from United States manufacturers, at first on a "cash and carry" basis,

later on credit under the Lend-Lease program.

By 1941, the German submarine offensive against Allied shipping

in the Atlantic threatened to starve Great Britain. Like Japan, she was

dependent on ocean-borne commerce to sustain her economy and

defend herself. The British population depended on imports for a third

of its food and for oil from North America and Venezuela to sustain

its lifeblood, but German submarines in 1940 and 1941 were sinking
merchant ships and tankers faster than the British could replace them.

Consequently, the United States gradually undertook a greater role in

the campaign that British Prime Minister Winston Churchill named the

Battle of the Atlantic. In September 1941, the U.S. Navy began to

escort convoys in the western part of the North Atlantic. Within a

month, a German submarine attacked a U.S. destroyer escorting a

convoy near Iceland, leaving several sailors dead or wounded. On

October 31, a German submarine sank a U.S. destroyer six hundred

miles west of Ireland, killing 115 of the crew.

Despite this loss of life, events in the Far East rather than in

Europe pushed the United States into World War II. By July 1941,

Japanese forces had occupied French Indochina, and U.S. economic

sanctions had cut off much of Japan's oil and other imported resources.

In October, the Japanese government decided on war, even as it

negotiated with the United States. Japanese military leaders hoped to

strike a blow that would paralyze the U.S. fleet in Hawaii long enough

to establish a defensive ring from Southeast Asia through the East

Indies and eastward in the Pacific as far as Wake Island. This strategic

plan would have provided Japan with unlimited access to the rich

resources of Southeast Asia. As the opening stage of this plan, a

Japanese aircraft-carrier task force attacked the American naval base at

Pearl Harbor and nearby facilities in Hawaii on December 7, 1941.

The Role of The Army Air Forces in the

Antisubmarine Campaign

The United States was not prepared for war. Though the Battle of

the Atlantic had raged since September 1939, the United States lacked

ships, aircraft, equipment, trained personnel, and a master plan to

counter any serious submarine offensive. However, steps taken just

before and shortly after the Pearl Harbor attack helped the U.S. Navy

enhance its submarine defenses. The U.S. Coast Guard was transferred

to the Navy in November 1941, and the next month President

Roosevelt named Adm. Ernest J. King Commander in Chief, United

States Fleet. In March, the admiral became Chief of Naval Operations

as well, giving him the authority and means to direct the U.S. effort in

the Battle of the Atlantic, particularly in the American Theater.

This theater included the North and South American continents,

except Alaska and Greenland, and the waters about the continents to

mid-Atlantic and mid-Pacific Oceans. After Pearl Harbor, the Navy

organized its existing East Coast naval districts into sea frontiers, with

the Eastern Sea Frontier extending from the Canadian border to

northern Florida. The Gulf Sea Frontier encompassed the Gulf of

Mexico as far south as the border between Mexico and Guatemala,

2
A Boeing B-17 Flying Fortress beginning an ocean

patrol from its base in the Panama Canal Zone.

most of the Florida Coast, the northern half of the Bahamas, and the

eastern half of Cuba. The Panama Sea Frontier covered the Pacific and

Atlantic coasts of Central America and Colombia, and the Caribbean Sea

Frontier included the rest of the Caribbean and the northeast coast of

South America.

To provide adequate antisubmarine measures in this vast area, the

Navy needed trained manpower and specialized surface vessels. As early

as 1937, it started training personnel for convoy escort duty in surface

vessels, but by 1941 had only a few qualified officers for this duty.

Shortly before the United States entered the war, the Navy's General

Board chose the Hamilton Class Coast Guard Cutter as the ideal

antisubmarine ship. It proved to be an outstanding American escort vessel,

but as late as October 1942 only five were on antisubmarine convoy patrol

in the North Atlantic. The Navy also had too few destroyers for its needs,

even with the use of World War I-era ships, and for the first few months

of the war had to rely on smaller craft, including civilian yachts, for

antisubmarine patrols.

The Navy's air arm in 1941-1942 was as inadequate as its

antisubmarine surface fleet. Initially, the Navy had no escort carrier,

a type that eventually was very effective against the German submarines.

It also lacked aircraft capable of long-range (radius of 400-600 miles) or

very-long-range (radius up to 1,000 miles) patrols over the ocean.

3
Pre-war plans called for the Army Air Forces (AAF) to support

naval forces in case of an emergency. To supplement its meager

antisubmarine forces, the Navy turned to the AAF, commanded by

General Henry ("Hap") H. Arnold. AAF doctrine, however, emphasized

strategic bombing, and the AAF had no equipment or trained personnel

for the specialized job of patrolling against, detecting, and attacking

submarines from the air.

The AAF's medium and long-range bombers, including the twinengine Douglas B-I 8 Bolos and North American B-25 Mitchells and

the four-engine Boeing B-17 Flying Fortresses and ConsolidatedVultee B-24 Liberators, were potentially capable of an antisubmarine

role. These carried bombs rather than depth charges and lacked radar or

other special submarine detection equipment. Also, like the Navy, the

AAF had many demands for the few aircraft on hand. The shortage of

aircraft equipped for antisubmarine war continued into mid-1943, with

fighters and light bombers often used as antisubmarine aircraft.

Initially, the AAF leadership considered the AAF's role in

antisubmarine war to be temporary, and the major thrust of its efforts

remained strategic bombing. Thus the AAF somewhat reluctantly began

flying antisubmarine missions in a two-front naval war waged off both

the East and West Coasts of the United States.

Operations off the West Coast

December 1941-February 1943

After the attack on Pearl Harbor, the greatest danger of submarine

attack apparently was along the West Coast of the United States, but

the Japanese submarine fleet never presented much of a threat.

Japanese strategic policy limited submarines primarily to attacks on

enemy naval forces, with merchant shipping being a purely secondary

target. Even if naval policy had been different, in December 1941

Japan had only twenty submarines capable of traveling from Japan to

the West Coast.

During December nine of these patrolled off the West Coast,

attacking ten commercial vessels and sinking one merchant ship and

three tankers. Then, between February and October 1942, four other

Japanese submarines patrolled off the West Coast up to a month at a

time. They sank seven ships, including a submarine, and on at least

three occasions attacked installations ashore, inflicting little damage.

No Japanese submarines operated off the West Coast again until late

1944, when one sank two more ships.

On November 28, 1941, the AAF ordered the Second and Fourth

Air Forces, the two organizations that shared responsibility for West

4
Adversaries in the Battle of the Atlantic

Relative Sizes of USAAF Aircraft and German Submarines

Lockheed A-29

North American B-25

Douglas B-18

Consolidated B-24

Boeing B-17

German Type VII

100'

The Type VII U-Boats were the most numerous German submarines in the North Atlantic.

5
Coast air training and defense, to support the Navy in patrolling against

submarines. Their commanders worked closely with Navy authorities to

institute offshore patrols that avoided duplication of effort and still

covered essential areas of coastal waters.

Lack of experience and different administrative and operational

methods initially clouded liaison between the AAF and the Navy. The.

establishment of a joint information center in late December 1941 at

San Francisco helped solve the liaison problems. Differing methods of

patrol created some interservice tension. The Navy used a search

pattern shaped like a fan, with every aircraft branching out from a

central point on diverging courses, while the Army Air Forces flew a

parallel track search pattern, with each aircraft on patrol flying parallel

within sight of the aircraft on either side. The AAF pilots soon adopted

the fan pattern in the interest of interservice cooperation and more

efficient coverage of the patrol areas. The Navy flew patrols close to

the shore, but the AAF antisubmarine missions ranged up to 600 miles

offshore from Seattle, Washington, in the north all the way south to the

coastline of Lower (Baja) California.

In December 1941, the AAF had only forty-five modem fighter

aircraft-thirty-five medium bombers and ten long-range

bombers-stationed on the West Coast. To meet the immediate need

for more long-range aircraft, on December 8, the AAF created a

temporary collection agency of aircrews and B-17s formerly bound for

the Philippine Islands. This "Sierra Bombardment Group" participated

in off-shore patrols until early January 1942 when the absence of

an immediate threat became obvious and scheduled movements of

aircraft to the Southwest Pacific could resume.

While the Sierra Bombardment Group provided short-term relief

from personnel and aircraft shortages, it did not solve problems

presented by untrained, inexperienced personnel and lack of

submarine detection equipment. The available aircraft were not

equipped with radar or other devices, and detection of enemy

submarines depended solely on eyesight. The antisubmarine aircrews

occasionally mistook whales and floating logs for Japanese submarines,

They frequently reported and attacked enemy submarines, but rarely

confirmed results. A B-25 crew of the 17th Bombardment Group

(Medium), Second Air Force, bombed a submarine near the mouth

of the Columbia River on December 24, 1941. They claimed it sank,

but in fact no Japanese submarine was sunk off the West Coast during

World War II.

In February 1943, the AAF ceased flying antisubmarine patrols

off the West Coast. Japanese submarines had not appeared off the coast

since October 1942, and Navy aircraft and surface vessel strength had

grown sufficiently strong to handle any new threats.

6
Operations off the East Coast

December 1941-June 1942

In complete contrast to the West Coast, German submarine

forces posed a deadly threat to U.S., British, Canadian, and other

Allied shipping off the East Coast of the United States. Because of

British reliance on imports, Germany's leaders sought to destroy

Allied shipping. Admiral Karl Doenitz, commander of Germany's

submarine force, had formulated a strategy of attacking Allied

shipping at weakly defended points to achieve the greatest destruction

at the least cost. Furthermore, Germany had the submarine force to

pursue Admiral Doenitz's strategy. It began 1942 with 91 operational

submarines; at the peak of its strength a year later, it had 212. These

submarines, sailing from bases in France, took about three weeks to

reach American waters. Modified to carry an extra twenty tons of fuel,

they could remain on patrol two to three weeks, and averaged fortyone days at sea. Admiral Doenitz managed to extend this time by

refueling and resupplying the operational submarines from specially

modified submarines. Called "milch cows," they carried enough fuel

and supplies to resupply other boats and extend their time at sea to an

average of sixty-two days with one refueling and eighty-one days with

a second refueling. The first submarine "milch cow" deployed at sea

in March 1942.

The sudden entry of the United States into World War II caught

Admiral Doenitz by surprise, with no submarines immediately

available to send to American waters. He allocated five long-distance

submarines, all he could quickly make ready, to Operation

DRUMBEAT, his code name for operations against shipping in U.S.

coastal sea-lanes. These sailed from Lorient, France, between

December 23 and 27, 1941. On January 11, 1942, some three hundred

miles east of Cape Cod, the leading submarine, U-123, commanded

by Captain Reinhard Hardegen, sank an Allied merchant ship, the first

combat loss in the American Theater. Three days later, Captain

Hardegen sank another ship just off the coast of Massachusetts.

Captain Hardegen and the rest of the German submariners used

tactics that Admiral Doenitz had developed during the interwar years.

Usually, the submarine would lie on the shallow continental shelf in as

little as 30 meters (100 feet) of water during the day, then surface to

attack at night. The submarine operated on the surface to obtain a

favorable position, then hit the target with two to four torpedoes. If the

ship did not immediately sink, the Germans sometimes gave the ship's

crew time to abandon ship, then finished the vessel off with shells

from the deck gun. As German submarine commanders realized the

vulnerability of Allied merchant shipping and the inability of the U. S.

.7
antisubmarine forces to respond or patrol, they sometimes attacked

from the surface in the daytime.

Using these tactics, the Germans between mid-January 1942 and

the end of June sank 171 ships off the East Coast, many of them

tankers. For several months, the German submarine offensive gravely

threatened the cargo carrying capability of the Allies. Not until the last

quarter of 1942 did the United States build merchant ships rapidly

enough to offset losses inflicted by the German submariners. During

the first half of 1942, the Allies lost three million tons of shipping,

mostly in American waters. The submarine attacks claimed about

5,000 lives, and the loss of irreplaceable cargoes grievously

endangered Great Britain's ability to continue the war.

This perilous situation resulted in part from the tragic U.S. delay in

taking such precautionary measures as controlling maritime traffic and

organizing submarine defenses. German submarine captains arriving in

American waters in the first half of 1942 found merchant ships following

peacetime sea-lanes and sailing practices. The ships, sailing

independently instead of in convoys, were silhouetted at night against the

brightly lit coast, making the job of the enemy much easier. U.S. military

leaders until May 1942 undertook little effective action to find and attack

submarines whose positions were known through distress signals from

torpedoed ships or to redirect merchant shipping away from waters where

attacks had taken place. While no one reason can be cited for the delay in

instituting defensive measures, the general state of American

unpreparedness is perhaps the best explanation.

Early in the war the AAF and the Navy pooled their meager

resources for antisubmarine patrols. In response to a Navy request, the

AAF on December 8, 1941, directed the I Air Support Command and I

Bomber Command to initiate patrols in the Eastern Sea Frontier. Ile I

Air Support Command's observation and pursuit (fighter) aircraft

patrolled out to 40 miles offshore from Portland, Maine, south to

Wilmington, North Carolina, but usually had fewer than ten aircraft per

day on patrol. The I Bomber Command relied on its medium B-25 and

B-I 8 bombers to fly up to 300 miles offshore and its heavy B-I 7s to

cover up to 600 miles out. On the average, however, until March 1942

this command had only three aircraft flying each day from Westover

Field, Massachusetts, and three from Mitchel Field, New York, not

nearly enough to patrol the Eastern Sea Frontier effectively.

Ile Army Air Forces obtained the assistance of the Civil Air Patrol

(CAP) to augment I Bomber Command's efforts. Organized a week

before the war began, the CAP consisted of civilian pilots willing to fly

their own aircraft off the coast to look for submarines and to assist in the

rescue of survivors. Receiving only aviation gasoline from the AAF, the

CAP began patrolling on March 8, 1942, eventually establishing

8
Two crewmembers fire the antiaircraft guns of a

German submarine at the attacking AAF aircraft.

twenty-one stations from Bar Harbor, Maine, to Brownsville, Texas.

With the help of the CAP, the I Bomber Command flew almost 8,000

hours in March, about as much as in January and February combined.

The additional patrols forced German submarines to remain submerged

except on the darkest nights.

As the number of patrols increased, the AAF overcame numerous

deficiencies in its antisubmarine efforts. Originally, aircraft were

unarmed or armed with bombs instead of depth charges. They could

not fly at night and none had radar before March 1942. The aircrews

lacked training in navigation, recognition of ships, and antisubmarine

attack tactics. In December 1941, forced to rely on eyesight alone,

they often reported incorrectly the sighting of surfaced and submerged

submarines. On December 29 near Newport, Rhode Island, an AAF

bomber dropped four bombs on a U.S. Navy destroyer that the aircrew

had mistaken for a submarine. Fortunately, the bombs exploded

harmlessly.

The United States sought the guidance of Great Britain, which

had been waging antisubmarine war against Germany since 1939. As

suggested by the British, the AAF and the Navy established a Joint

Control and Information Center in New York City on December 31,

1941. The center tracked the movements of merchant shipping, plotted

enemy contacts, and determined the locations of all surface and air

antisubmarine patrols.

One British capability the Americans remained unable to exploit

until mid-1943 was intelligence that virtually pinpointed the locations

of enemy submarines. During the interwar period, Germany developed

9
a machine, called Enigma, to encipher the military codes used to

transmit radio messages. Early in World War T1 the British, in

cooperation with the French and Polish governments-in-exile,

developed the means to break the German codes enciphered by the

Enigma, with intelligence derived from the broken codes known as

ULTRA. The British routed convoys around the locations of enemy

submarine wolfpacks, using ULTRA information as well as

intelligence derived from aerial reconnaissance, radio fingerprinting

(identification of individual enemy radiomen by their distinctive

method of sending messages), and radio direction-finding.

Shortly after the United States entered the war, Great Britain agreed

to provide pertinent ULTRA intelligence to the U.S. military. However,

on February 1, 1942, Germany replaced its original Enigma machines on

the Atlantic U-boat net with a new, more complex machine employing

more encrypting rotors, resulting in codes that the British could not

decipher. Not until December 13, 1942, six weeks after the capture of

German code books related to the new Enigma from a badly damaged

enemy submarine, were the British able to again read the German U-boat

code. (They soon discovered that the Germans had broken the Allied

code directing convoy traffic, a discovery that resulted in a new British

code in March 1943.) By August, the British and Americans were

reading German messages almost as soon as they were intercepted, but

for much of the time between January 1942 and October 1943, when the

Army Air Forces participated extensively in the antisubmarine war,

ULTRA intelligence was sporadic or non-existent.

To add to the intelligence woes of the Americans in 1942, the

Navy initially failed to send the information it did receive from the

British to the using commands. Consequently, the intelligence was not

being used in operations against the enemy, Even if it were

disseminated, intelligence data often lost its usefulness because it was

not quickly communicated from Navy to Army organizations or down

the chain of command in either service.

In large part, the intelligence lapse stemmed from the chaos and

confusion that Army and Navy commands suffered in the first few

months of the war. This confusion also led to faulty tactics that usually

resulted in unsuccessful attacks on enemy submarines. Attacked

submarines often escaped because the aerial and surface attacks were

sporadic rather than sustained. Through inexperience, poor training, and

lack of adequate forces, both Navy surface forces and AAF aircrews

often failed to follow up initial antisubmarine attacks.

Once again the AAF and the Navy turned to the British for applied

lessons in tactics. British tactics exploited the weaknesses of the

submarine, which had to surface, usually at night, to recharge its batteries,

10
ventilate the boat, and permit crewmembers a chance to come topside.

Constant aerial patrolling to as far as 600 miles out to sea restricted

opportunities for submarines to operate on the surface. Until the first

AAF aircraft received radar sets in March 1942, the submarines could

surface and attack almost at will during dark nights or inclement weather,

but the advent of night flights using radar to locate surfaced submarines

added considerably to the value of the routine antisubmarine air patrol.

By June 1942, I Bomber Command aircraft had vastly increased

sightings of and attacks on German submarines.

As the British had learned, when an aircrew sighted an enemy

submarine, it had to act quickly to achieve surprise. An attack later than

fifteen to thirty-five seconds after the submarine submerged usually

proved unsuccessful. By flying in clouds and attacking at an angle from

fifteen to forty-five degrees, the pilot increased the chances of a hit or

near-miss. The attack itself required the aircraft to fly as low as possible,

preferably about fifty feet above the water, and to drop the depth bomb

within twenty feet of the submarine's pressure hull. As the aircraft passed

over the submarine, the aircrew would fire the machine guns in an

attempt to damage it and suppress antiaircraft fire.

The first successful AAF aircraft attack on a German submarine,

U-701, on July 7, 1942, incorporated these tactics. The official history

of I Bomber Command records the attack from an

A-29 piloted by Lt. Harry J. Kane of the 396th Bombardment

Squadron.

Lt. Kane attacked by the book. He was flying a routine patrol

from Cherry Point, N.C. He sighted a submarine seven miles

away. Since he was using cloud cover, he was able to approach

it undetected, closing in on a course of zero degrees relative to

the track of the submarine. He attacked from fifty feet at 220

miles per hour, releasing three MK XVII depth charges in train

about twenty seconds after the target submerged. The

submarine was still visible underwater as the bombs fell. The

first hit short of the stem; the second, just abaft of the conning

tower; the third, just forward of the conning tower. Fifteen

seconds after the explosions, large quantities of air came to the

surface, followed by seventeen members of the crew.

Accumulated experience-coupled with British coaching,

improved radar, depth bombs, and other equipment-resulted in

noticeably higher levels of success for AAF antisubmarine patrols

during July, August, and September 1942. In the previous quarter,

only seven of fifty-four attacks resulted in damage to submarines, but

in the third quarter, eight of twenty-four attacks damaged submarines,

not counting the one sunk on July 7.

11
A Lockheed A-29, the type of aircraft flown by the crew

that made the first successful Army Air Forces attack

on a German submarine in the American Theater.

By this time, the Americans owed a great deal to the British for

sharing their antisubmarine experience. But in one area they appeared

slow to assimilate British methods. Early in the Battle of the Atlantic,

Great Britain had recognized the need for close cooperation between

sea and air antisubmarine forces at higher as well as operational levels

of command. But such cooperation at the higher levels of the AAF

and the Navy was frequently elusive, partly because of historical

rivalry. Between World Wars I and II, the two services had argued

bitterly over the roles of their respective air arms, the Navy insisting

on responsibility for all missions over the ocean and the Army

insisting on controlling all long-range, land-based aircraft. The

jurisdictional problem continued into the war and at times

handicapped efforts to counter enemy submarine attacks in American

waters.

Partially as a result of the jurisdictional dispute, multiple

headquarters had overlapping responsibility for antisubmarine

operations. Since its doctrine emphasized centralized operational

control of aircraft, the AAF found this situation objectionable. To

achieve centralization, General Arnold in March 1942 proposed to

Admiral King the establishment within the AAF of an organization to

conduct all air operations against submarines. The Navy did not accept

this idea because it would give the Army a traditionally Navy mission

and bring naval aircraft under Army control. Most AAF units involved

in antisubmarine operations came under I Bomber Command, and, in

12
an effort to reduce organizational confusion, I Bomber Command was

placed under the operational control of the Eastern Sea Frontier on

March 26. Gradually, I Bomber Command reoriented the training of

its flying personnel, obtained additional aircraft, and adapted its

equipment to the antisubmarine mission. General Arnold, along with

most other AAF leaders, believed that progress in bringing the

AAF's antisubmarine resources and operations under one

headquarters was largely offset by Navy policies. The Navy allocated

the AAF antisubmarine squadrons to the sea sector commanders and

would not ordinarily allow aircraft allocated to one sea sector or

frontier to operate in another. Transfer of aircraft from one sea

frontier to another to meet changing submarine threats proved

difficult and usually too late.

This significant difference in Navy and AAF doctrine

aggravated disputes caused by interservice rivalry. The AAF

perceived the Navy command structure as inflexible and its strategic

concept as essentially defensive. The Navy confirmed these

perceptions as it built up its forces until it could institute a coastal

convoy system, one of the most important and effective defensive

measures. The first convoy sailed from Hampton Roads, Virginia,

southward bound, on May 14, 1942. Admiral King sought increased

support from the AAF for convoy escort duties. The Army Air

Forces preferred to concentrate on long-range over-water patrols, but

until mid-1943, the AAF had to divert considerable aircraft to

convoy escort duties, probably the best use of scarce resources.

The formation, equipping, and training of effective sea and air

antisubmarine forces against the German offensive on the East Coast

required time. The Navy, supported by the AAF, gradually

progressed with various defensive measures and increasingly

effective air patrols forced the Germans to greater caution in the

waters of the Eastern Sea Frontier. By June 1942, German

submariners had turned to the less dangerous waters of the Gulf of

Mexico and the Caribbean Sea.

Operations in the Gulf of Mexico and the Caribbean Sea

January-October 1942

Only five ships had been sunk in the Gulf Sea Frontier in the

first four months of 1942, but in May 1942, submarines sank fortyone ships, totalling 219,867 gross tons, with 55 percent tanker

tonnage. By July 1942, the enemy had sunk sixty-two ships in the

Gulf. As many as four enemy submarines at a time prowled the Gulf

of Mexico between May and August 1942, taking advantage of

skimpy air patrols and the lack of a convoy system.

13
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The shift of the German submarine offensive to the Gulf

overwhelmed the resources of the Navy and the AAF, which were

barely adequate to defend against submarines in the Eastern Sea

Frontier. The Navy had created the Gulf Sea Frontier in February

1942 with minimal surface and air forces, and the AAF had

contributed only fourteen observation aircraft and two worn-out

B-18s. To counter increased submarine attacks, the AAF, between

May 8 and 10, sent a squadron of light bombers (A-29s) to

Jacksonville, Florida, and six medium bombers (B-25s) to Miami

and on May 20-21 sent a detachment of B-25s to Havana, Cuba, to

patrol the Yucatan Channel. On May 26, the First Air Force created

the Gulf Task Force and stationed it at Miami. This organization,

which continued to operate until November 1942, cooperated with

the Commander, Gulf Sea Frontier, to provide operational control of

all AAF aircraft that flew antisubmarine patrols in the area. At the

end of July 1942 the Navy instituted a convoy system in the Gulf of

Mexico, and German submarines faced the same dangers they had

off the East Coast. On September 4, 1942, the United States lost the

last ship sunk by enemy action in the Gulf of Mexico, as Admiral

Doenitz withdrew all submarines from the Gulf.

The devastation of German submarine attacks in the Caribbean

Sea Frontier matched that in the Gulf Sea Frontier. Having dispatched

a sizeable force to the U.S. East Coast, Admiral Doenitz fixed the

opening of the Caribbean operation for the new moon period of

February 1942. On the 16th, a German submarine sank two tankers

off San Nicholas, Aruba, then moved into the harbor and shelled a

refinery, inflicting little damage but killing four people. In February

and March, the Germans operated six submarines in the Caribbean

Sea, each patrolling for two to three weeks before returning to France.

Then, in April, a second wave of submarines arrived in the area;

some, refueled and replenished northeast of Bermuda by "milch cow"

submarines, stayed up to six weeks. By July, the German submarines

had sunk some 141 ships and sank another 173 ships in the Caribbean

Sea Frontier and its approaches by September. Between February and

September, the German submarines sank an average of one and a half

ships each day, destroying over one million gross tons in the

Caribbean and adjacent waters.

U.S. military leaders had been aware of possible threats in the

Caribbean and the Gulf at the beginning of the war. The Army Air

Forces, fearing an attack on the Panama Canal, in December 1941

transferred to the Canal Zone eighty additional fighter aircraft, nine

heavy bombers, and four mobile radar sets. In February 1942, the

Sixth Air Force assumed responsibility for the aerial defense of the

Panama Canal. Major General Davenport Johnson, Commander of the

16
A depth bomb exploding near the stem of a U-boat

caught on the surface sends spray high in the air.

Sixth Air Force, concentrated aerial patrols on the Pacific side in fear

of a carrier-borne Japanese attack. Then in April 1942, when the

German submarine threat became evident, the Sixth Air Force,

cooperating with the Navy, instituted antisubmarine patrol flights as far

east as Curagao. Most flights were by tactical aircraft, such as Bell P39 Airacobras and Northrup A-17s, which could fly only during

daylight; lacking radar and trained observers, the pilots had little luck

in spotting enemy submarines. On the other hand, Sixth Air Force

aircraft occasionally attacked friendly ships and submarines, fortunately

without damaging them.

The AAF in February 1942 organized a provisional force, later

designated the Antilles Air Task Force. Scattered about the Caribbean

in Trinidad, Curaqao, Aruba, St. Lucia, Surinam, British Guiana,

Puerto Rico, St. Croix, and Antigua, it consisted of about forty B-18

medium bombers, seven Douglas A-20 Havoc light bombers, and

several fighter aircraft. Although remaining substantially the same size

through the year, the task force obtained radar-equipped aircraft, vastly

increasing its antisubmarine capability. Prior to July the aircrews

reported few sightings of or attacks on submarines, but in July and

August attacked twenty. To supplement these efforts, the First Air

Force sent six B-18s equipped with radar to the Caribbean Sea

Frontier. This unit, shuffled from one island and commander to another

from August to November 1942, accomplished little.

17
The Navy extended the convoy system to the Caribbean Sea

Frontier, with the first convoy sailing on July 10, 1942, between

Guantanamo, Cuba, and the Canal Zone. In reaction, Admiral Doenitz

redeployed his submarines to the Trinidad area where targets were

lucrative and relatively unprotected. In August, the submarines sank

only one ship in the rest of the Caribbean while destroying ten near

Trinidad. Because of the extensive Caribbean air patrols, the

submarines attacked independently, continuing their success into

September, sinking an additional twenty-nine ships totaling 143,000

tons.

The AAF stationed detachments of B-I 8s at Trinidad, Curaqao,

Dutch Guiana, and British Guiana in June 1942; but these aircraft,

lacking radar, could not stem the German efforts in the area during

July and August. On August 17, to aid the Caribbean Sea Frontier, the

AAF sent a detachment of B-I 8s equipped with microwave radar to

Key West, Florida. The detachment, which always patrolled the

Trinidad area, moved to other bases in the Caribbean and was based at

Trinidad between September 22 and October 16, 1942.

Operations of the AAF Antisubmarine Command

October 1942-August 1943

By October 1942, the AAF had been engaged in antisubmarine war

for almost a year. During that time it had laid the basis for an effective

organization and made plans for a larger antisubmarine force. To take

advantage of these plans, the AAF on October 15, 1942, activated the

Army Air Forces Antisubmarine Command (AAFAC) to replace I

Bomber Command, which held most of the AAF's antisubmarine

resources. I Bomber Command furnished the personnel, aircraft, and

equipment for the new organization, which remained under Navy

operational control. The AAFAC provided a greater unity of command of

antisubmarine forces in the War Department, resulting in increased

flexibility and more effective operations. The I Bomber Command had

been handicapped in its efforts because its primary mission remained

long-range bombardment. The antisubmarine task was secondary and

presumably temporary. "Now," in the words of the official history of the

Army Air Forces in World War II, "as an officially constituted

antisubmarine unit, the AAFAC was able to attack its problems with

undivided energy, free at least from any immediate uncertainty as to its

mission." The reorganization extended to subordinate elements as well.

By November 20, 1942, the AAFAC had organized the squadrons it had

inherited from I Bomber Command into the 25th and 26th Antisubmarine

Wings with headquarters at New York and Miami respectively.

18
In January 1943, the command had only nineteen squadrons and

only twenty B-24s, the aircraft type most useful for long-range

antisubmarine patrolling. The command grew rapidly until, by September

1943, there were twenty-five antisubmarine squadrons, most of which

flew B-24s modified for antisubmarine war. At the end of 1942, most of

these squadrons operated in the Gulf, Caribbean, and Eastern Sea

Frontiers on endless patrols with few sightings and fewer attacks. The

Navy continued to require the AAFAC to commit sizeable forces in these

areas to counter what was a diminishing German threat-the five to ten

submarines that Admiral Doenitz kept along the U.S. coast and in the

Caribbean Sea. From September 1942 until mid-1944 these few

submarines maintained pressure on the American antisubmarine forces.

To counter the submarine threat in the Caribbean, the AAF

Antisubmarine Command continued to fly patrols and escort coverage

from Cuba. These operations, which had begun as early as June 1942,

generally kept the German submariners from making successful attacks

in the Caribbean Sea Frontier, although two ships were sunk there as late

as July 1943.

The Germans found the hunting more profitable in the area of

Trinidad until mid-year 1943. The AAFAC consequently based

B-18s at Edinburgh Field, Trinidad, from early January until August

1943. In November and December 1942, German submarines sank

eighteen ships. Increased aerial patrols paid off with no losses of

friendly ships near Trinidad from January to July 1943. During this

time, the AAF B-18s engaged mostly in convoy escort and coverage

missions. In July-August, German submarines sank four merchant

vessels. The AAF antisubmarine squadrons, flying both B-24s and B18s, made six attacks and participated in two killer hunts to foil the

enemy offensive in Trinidad waters.

In addition to the Trinidad area, the German submarines operated

extensively in the South Atlantic Ocean in 1943, where merchant

vessels sailed independently because there was no convoy system; The

AAFAC sent a detachment of B-24 aircraft in May from Trinidad to

Natal, Brazil, to patrol the South Atlantic sea-lanes at ranges beyond

the reach of the Brazilian Air Force. The next month, the detachment

moved to Ascension Island, added two more aircraft, and flew patrols

over the South Atlantic Ocean until August 1943.

Although important, the AAFAC's operations from October

1942 in the Eastern Sea Frontier, the Gulf Sea Frontier, and the

Caribbean Sea Frontier constituted only a small part of the war against

the German submarines. In fact, by mid-summer 1942, the U.S.

Navy's and the AAF's antisubmarine warfare efforts had forced

Admiral Doenitz to withdraw most of his forces from these areas. The

German submarines moved back to the North Atlantic to exploit

19
weaknesses in Allied antisubmarine efforts there. Consequently, the

AAFAC turned to the reinforcement of the meager antisubmarine air

forces in Newfoundland.

Operations from Newfoundland

October 1941-July 1943

In October 1941, far to the north, an AAF detachment of four to

six B-17s had begun antisubmarine patrols over the northwest Atlantic

Ocean from Gander Lake, Newfoundland. The B-I 7s were armed with

machine guns and bombs but carried no radar or depth charges. In

July 1942, the 421st Bombardment Squadron, also flying B-17s and

with a primary mission of long-range bombardment training, replaced

the detachment. The squadron cooperated with Royal Canadian and

U.S. Navy organizations in Newfoundland to carry on its secondary

mission of antisubmarine war. Then, in the fall of 1942, the AAF

Antisubmarine Command made antisubmarine patrol the squadron's

primary mission, redesignating it the 20th Antisubmarine Squadron.

The 421st had replaced the B-17 detachment in Newfoundland

even as the Germans increased submarine activity in the 500-mile gap

between 25 and 45 degrees West longitude that the Allies could not

cover with land-based aircraft. This gap in air coverage allowed the

German submarine wolf packs to attack convoys without being spotted

or attacked from the air. Admiral Doenitz organized the submarines in

two screens running in a northwesterly direction at either end to catch

the convoys as they sailed into the gap. The sea-lanes northeast of

Newfoundland, marking the eastern edge of Allied air coverage, were

especially dangerous.

The Allied convoys sailed under several other disadvantages

from September 1942 until March 1943. Fuel shortages kept them

close to the shortest track to and from Great Britain. Winter weather

favored the submarines which often approached the convoys without

being detected until too late. For most of 1942 the British could not

decipher Enigma transmitted code, but the Germans could read the

Allied convoy code. The Germans located and intercepted Allied

convoys more frequently and successfully during this period than at

any other time in the war.

Germany redeployed its submarines to the mid-Atlantic in June

and July 1942, and the offensive became effective in July and August.

By then, the enemy had eighty-six submarines in the North Atlantic,

and approximately this number remained operational there until June

1943. In August and September 1942, the submarines located twentyone of sixty-five convoys that sailed, attacked seven, and sank fortythree Allied ships.

20
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During the Allied Conference in January 1943 at Casablanca,

French Morocco, Great Britain and the United States agreed to deploy

B-24 aircraft to patrol the mid-Atlantic gap. Modified B-24s, with a

radius up to 1,000 miles, could fly day or night in all but the worst

weather to detect and attack submarines. The British immediately began

operating B-24s from bases in Ireland and Iceland to cover the eastern

part of the gap, but the U.S. Navy did not send any aircraft to cover the

western stretches of the mid-Atlantic. During February 1943 twenty-two

ships totalling almost 200,000 tons were lost, mostly in the western gap.

The next month in the Atlantic, the Allies lost thirty-eight ships of

750,000 tons and an escort in four convoys.

On March 18, a B-24 detachment of the 25th Antisubmarine Wing

established a headquarters at St. John's, Newfoundland, and began

antisubmarine patrols on April 3, 1943. By the end of the month the AAF

Antisubmarine Command had three B-24 squadrons operating from St.

John's and Gander Lake, Newfoundland. The squadrons engaged in

convoy coverage and in broad offensive sweeps ahead of the convoys. In

April and May they made twelve sightings of German submarines, which

resulted in three attacks, but the B-24s did not sink a submarine.

During April 1943, Allied long-range B-24 aircraft and escort

carriers closed the mid-Atlantic gap in air coverage, effectively

neutralizing the German submarine offensive. That month the

Germans sank only three Allied merchant vessels while losing four

submarines. In May Germany lost thirty-one submarines in the North

Atlantic, and on May 26, Admiral Doenitz withdrew his boats from

the North Atlantic, essentially conceding victory to the Allies in the

Battle of the Atlantic. Almost 1,700 Allied ships crossed the ocean in

June and July 1943 without a loss.

Development of Antisubmarine Equipment and Tactics

Admiral Doenitz recognized that improvements in Allied tactics

and weapons had turned the tide of war against the German

submarines. He noted in a memorandum dated June 1943:

The war at sea is at present characterized by a decrease in the

victories of our Navy against enemy merchant shipping. The

principal exponent of this type of warfare, the submarine, is

limited in operational capacity by the ever-growing strength of

the enemy's antisubmarine defenses and in particular by the

enemy Air Force, using as yet unknown equipment and weapons.

The "unknown" equipment and weapons owed their existence at

least in part to the I st Sea-Search Attack Group which General Arnold

22
A pre-war Douglas B-18, when equipped with a magnetic anomaly

detector boom and nose radar, was a formidable threat to U-boats.

established on June 17, 1942, at Langley Field, Virginia. The group

engaged in the development of equipment and tactics best suited for

aerial antisubmarine warfare. Among the devices that the group helped

develop or test were the absolute altimeter, the magnetic anomaly

detector (MAD), the radio sonic buoy, improved airborne depth

charges, long-range navigation, and airborne microwave radar.

The absolute altimeter used a modified microwave radar to

determine an aircraft's exact altitude to within ten feet. This altimeter,

replacing the less accurate barometric instrument, permitted aircraft to

fly safely as low as 50 feet. The low altitude attack substantially

improved the chances of destroying the target. This device was

standard equipment on AAF antisubmarine aircraft by 1943.

The magnetic anomaly detector operated by sensing a change in

the magnetic field of the earth, an anomaly that could be produced by

the steel hull of a submarine. Aircraft outfitted with this device would

patrol in an area where a submarine had been spotted but had

submerged. Combined with the use of a radio sonic buoy to listen for

the sounds of a submarine, the MAD permitted an intensive search

with a high probability of success.

Another important development was the use of LORAN (longrange aid to navigation). The aircraft received radio signals from three

known points, allowing the navigator to pinpoint his location to within

four miles at a range of 1,200 to 1,500 miles from transmitters.

LORAN permitted efficient control of converging forces. LORAN

coverage extended over the Eastern Sea Frontier, Gulf Sea Frontier,

and most of the Caribbean Sea and North Atlantic Ocean.

23
The 1st Sea-Search Attack Group also helped develop an

effective depth bomb with shallow fuse settings for about 25 feet.

Eventually, the Americans and British developed a blunt depth bomb

that sank slowly and exploded at the desired depth to destroy the

submarine. This depth bomb became standard in early 1943.

Perhaps the most important task of the Ist Sea-Search Attack

Group was to develop techniques for using Airborne Surface Vessel

Detection (ASV) radar to find surfaced submarines. The radar that

eventually went into production was ten-centimeter wave equipment,

known as ASV-10. The British had developed a long-wave ASV

radar and used it to find submarines in 1941-1942. As early as March

1942, the I Bomber Command had four B-18s outfitted with the longwave radar sets, but the Germans outfitted their submarines with a

long-wave radar detector that effectively countered the British radar.

The United States quickly developed the microwave radar, which the

Germans never effectively countered. The first microwave sets were

hand-manufactured and delivered to the Ist Sea-Search Attack Group

in June 1942. By February 1943, a skilled radar operator could

identify surfaced submarines at more than 40 miles and even the

conning tower of a boat running decks awash at 15 to 30 miles.

Radar sets were notoriously unreliable and difficult to maintain, and

scientists assigned to the 1st Sea-Search Attack Group found much of

their time consumed by seminars in the field on basic functions and

maintenance of equipment. Consequently, the AAF established a unit in

the group to train ground personnel in its proper maintenance.

Initially the ASV-10 radar sets were placed on B-18 medium

bombers flying antisubmarine patrols. Some 90 B-I 8s carried the

equipment by the end of June 1942, but the Allies needed the microwave

radar on the B-24. Equipped with auxiliary fuel tanks, microwave radar,

and a powerful search light, this very long-range bomber was ideal for

extended antisubmarine patrols. The AAF outfitted its first two

microwave radar-equipped B-24s in September 1942, and the 1st SeaSearch Attack Group acquired a squadron of B-24s in December.

Using the B-18s and B-24s assigned to it, the 1st Sea-Search

Attack Group trained combat crews in the tactical employment of new

equipment. In general, the Army Air Forces employed three broad types

of antisubmarine operations: routine aerial patrol of waters in which an

enemy threat might exist; air escort or coverage of convoys within range

of land-based aircraft; and intensive patrol of an area in which one or

more submarines had been spotted, an operation the AAF termed a

"killer hunt" (in contrast to the Navy expression "hunter-killer"). At

various times, each of these operational tactics had its place in the

antisubmarine war.

24
Early in the war, the Army Air Forces usually used the aerial patrol

to restrict and hamper enemy operations. Such flying required precise

navigation and reliable communications, and the crew had to identify

surface craft accurately to avoid attacks on friendly vessels. However, an

aircrew on routine antisubmarine patrol could fly hundreds of hours

without sighting a submarine. As most German submarines withdrew in

the summer of 1942 from American waters, the routine patrols, with

virtually no chance of spotting an enemy submarine, became the nemesis

of the Army aircrews.

Aerial escort of convoys came close to being as resented as the

routine patrols. The AAF considered these antisubmarine operations to

be primarily defensive in character, but they were absolutely essential

to prevent enemy submarines from attacking convoys. After the

institution of the coastal convoy system on May 15, 1942, the Navy

frequently called on the Army Air Forces to protect convoys, initially

between Key West and the Chesapeake Bay, later in the Caribbean.

Although convoy duty was essential, the AAF preferred the

offensively oriented killer hunt. This tactic most effectively used the

newly developed sonic buoys, magnetic anomaly detectors, and

microwave radar. A patrolling aircraft that spotted and unsuccessfully

attacked a German submarine would radio its location to its home

base. The information would be passed on to Navy authorities, who

would dispatch a force of ships and aircraft to maintain contact with

the submarine and attack it as the opportunity arose.

The killer hunt took large numbers of aircraft and surface vessels

from normal convoy escort and patrols, and the Navy did not regularly

employ it until mid-1943. The escort aircraft carriers used this tactic

very effectively against German submarines, including the "milch

cows." The escort carriers coupled with ULTRA allowed the Allies to

attack not just defensively, as in convoy escort, or fortuitously, as in

aerial patrol, but also actively by seeking out the enemy submarines.

Between June and October the escort carriers, guided by ULTRA

intelligence, located and destroyed nine of the ten refueling

submarines operating in the Atlantic Ocean.

The first killer hunt to result in a destroyed submarine occurred

much earlier in the Gulf Sea Frontier on June 10-13, 1942. A German

submarine, U-157, sank a ship north of Cuba on the night of June 10.

Within three hours, a radar-equipped B-18 out of Miami was

patrolling in the vicinity and early on the 11 th unsuccessfully attacked

the surfaced submarine. Other AAF B-18s in the area contacted and

attacked the submarine several times over the next two days.

Meantime, five Navy ships out of Key West sailed to the area.

Making sound contact with the submerged submarine on the 13th, the

Navy crews sank it with depth charges.

25
Dissolution of the AAF Antisubmarine Command

The killer hunt involved close cooperation among the operational

forces of the U.S. Army Air Forces and the U.S. Navy. Unfortunately,

this cooperative attitude did not lessen interservice rivalry concerning

organization, control, and use of land-based aircraft. The AAF deemed

the Navy's continuing operational control of its aircraft an intolerable

situation, especially since the Navy kept most of the Antisubmarine

Command's aircraft on endless patrol off the East Coast. To meet the

AAF's objections and achieve better control and coordination between

the services, U.S. Army Chief of Staff, General George C. Marshall,

proposed in April 1943 a centralized antisubmarine organization under

the Joint Chiefs of Staff. Admiral King rejected this proposal but on

May 20, 1943, established the Tenth Fleet, a Navy command with

jurisdiction over all antisubmarine activities. Although the Tenth Fleet

brought needed order to the American antisubmarine effort, Army

leaders remained unhappy because the AAFAC remained under the

Navy's operational control. Besides, in the opinion of General Arnold

and the AAF leadership, the Navy appeared to be duplicating the AAF's

efforts. By this time, the Navy was receiving large numbers of B-24s to

use on antisubmarine patrols.

On July 9, 1943, after several meetings, the Army and the Navy

agreed that the AAF would withdraw from antisubmarine operations. In

accordance with this agreement, the AAF by October 6 turned over

seventy-seven B-24s configured with antisubmarine equipment to the

Navy in return for an equal number of unmodified B-24s from the Navy

allocation. On August 31, the Army Air Forces redesignated the

AAFAC as the I Bomber Command and assigned it to the First Air

Force, redesignating the antisubmarine squadrons as heavy bombardment

squadrons. The 25th and 26th Antisubmarine Wings were disbanded, but

two antisubmarine groups overseas continued operations into October

1943 before being inactivated. Thus, the AAF ended its antisubmarine

mission, mostly disdained in spite of its strategic significance as

temporary and secondary to the AAF's responsibilities as a strategic

bombing force.

German submarines sank fewer than twenty ships in the Atlantic

Ocean between September 1943 and the end of the war. Still, the

submarine threat tied down large Allied naval and air forces. Hitler

recognized the Atlantic Ocean as his first line of defense in the West and

the danger of the antisubmarine forces if they should be released to

undertake other military tasks against Germany. Thus, the submarines

operated until the end of World War II, even returning in small numbers

from time to time to the Caribbean Sea or the East Coast of the United

States.

26
Death of a Submarine.

Top-the long white wake of

a sub cruising on the surface.

Above-the submarine

desperately attempts to evade

an attack.

Right-exploding depth

bombs straddle the

submarine.

Below-after the attack, only

debris and the bow show as

the sub settles to the bottom.
AAF Contributions to the Antisubmarine War

Statistics underline the menace of the German submarine

offensive. Submarines sank over 2,600 Allied ships, totaling about

15,000,000 tons. Germany built 1,162 submarines, of which 785 were

sunk, 156 surrendered at the end of the war, and the rest scuttled or

otherwise destroyed. German submarines operated between September

1939 and May 1945 not only in the North Atlantic and American

waters but also in the South Atlantic, Caribbean Sea, Gulf of St.

Lawrence, Mediterranean Sea, Indian Ocean, Kola Inlet in North

Russia, as well as around the Cape of Good Hope and along the coasts

of Australia and Brazil.

During the Battle of the Atlantic the Canadians and the British

sank most of the German submarines destroyed in the American

Theater. The U.S. Navy and the AAF cooperated with Canadian and

British forces to stifle the German submarine offensive off the East

Coast, in the Gulf of Mexico and the Caribbean Sea, and in the North

Atlantic Ocean. Since the Japanese made relatively few submarine

attacks off the West Coast, the AAF contributions there mostly

amounted to reassuring the public and governmental officials that

antisubmarine operations were in place to defend shipping and deter

the enemy.

During the war, increasingly effective antisubmarine air patrols

resulted from deployment of modified B-24s, development of various

finding aids and other technological advances, and experience in the

specialized tactics of hunting and attacking submarines. After the war,

Admiral Doenitz cited the radar-equipped very long-range B-24 as a

decisive factor in the defeat of the German submarines in the North

Atlantic. The AAF and the U.S. Navy explored the best tactical

combination of radar, depth bombs, and the magnetic anomaly

detector in the aerial search for submarines. Working together at the

tactical level, the two services conducted a successful offensive action

against enemy submarines, helping to turn the tide of submarine war

against the German submarine fleet within about eighteen months.

As part of the overall Allied antisubmarine effort, the Army Air

Forces significantly affected the outcome of the campaign. In terms of the

force available, the AAF increased its antisubmarine force from a few

obsolete observation aircraft, medium bombers, and B-17s, all without

radar, to 187 operational B-24s, 80 B-25s, 12 B-17s, and 7 Lockheed

B-34 Venturas, most equipped with microwave radar and other detection

equipment. These 286 aircraft were assigned to the Antisubmarine

Command when, on August 24, 1943, the AAF withdrew from

antisubmarine operations in the American Theater. In this theater, AAF

aircraft flew over 135,000 operational combat hours on antisubmarine

28
patrols. Altogether, the Army Air Forces participated in ninety-six attacks

on German submarines between December 7, 1941 and August 24,

1943. These statistics do not include the contribution of the AAFAC

in the Antisubmarine Campaign, European-African-Middle Eastern

Theater, nor of the Army Air Force's bombers which frequently

attacked the German submarine bases and sometimes sank submarines

anchored in their berths.

The AAF's antisubmarine campaign harassed the Germans to the

point of ineffectiveness. Even the efforts of the small unarmed Civil

Air Patrol aircraft in the shallow coastal waters contributed to this

outcome. The German policy from the beginning of the war was to

withdraw from areas that became too dangerous because of heavy

aerial patrols. By May 1943, Germany had lost the strategic initiative

in the Battle of the Atlantic. Aircraft had forced the enemy to

submerge so frequently and stay down for such extended intervals that

their targets escaped and U-boat activity became so handicapped that

the returns barely justified the expense.

Suggested Readings

Wesley F. Craven and James L. Cate, eds., The Army Air Forces

in World War II (Chicago: University of Chicago Press, 1948, reprint

Washington DC: Office of Air Force History, 1983).

Michael Gannon, Operation Drumbeat (New York: Harper &

Row Publishers, 1990).

Guinter Hessler, German Naval History: The U-Boat War in the

Atlantic, 1939-1945 (London: Her Majesty's Stationery Office, 1989).

Terry Hughes and John Costello, The Battle of the Atlantic (New

York: The Dial Press/James Wade, 1977).

David Kahn, Seizing the Enigma (Boston: Houghton Mifflin Co.,

1991).

Montgomery C. Meigs, Slide Rules and Submarines: American

Scientists and Subsurface Warfare in World War II (Washington DC:

National Defense University Press, 1990).

Samuel Eliot Morison, History of the United States Naval

Operations in World War II (Boston: Little, Brown and Co., 1947).

John Winton, Ultra at Sea (New York: William Morrow and

Co., 1988).

William T. Y'Blood, Hunter-Killer (Annapolis: Naval Institute

Press, 1983).

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