Lesson 22 WW II -- Second Battle of the Atlantic, Pt 2.

Lesson 22

WW II -- Second Battle of the Atlantic, Pt 2

Allied Strategy

• Protect existing shipping

• Build to replace shipping losses, expand fleet

• Go on the offensive against the U-boats• Improve intelligence on U-boat operations

• Close Mid-Atlantic Gap

• Develop Hunter-Killer teams

Signals Intelligence

Source

Enigma

( SIGINT )

Enigma

Source

Enigma

Source

Bletchley Park

Alan Turing’s “Bombe”

Enigma

Source

British intelligence received its first Enigma machine in 1939 from Polish military

Additional machines captured by Royal Navy

• May 9, 1941: U-110 off Iceland

• October 30, 1942: U-559 in the Mediterranean

USN captured U-505, June 4, 1944

Direction Finding

High Frequency Direction Finding (HF/DF)

“Huff-Duff”

( ELINT )

German subs required to report positions

Allies used information to reroute convoys

• Later used to direct Hunter- Killer task forces

Source: The World At WarMid-Atlantic Gap

Maritime Patrol Aircraft

SourceRAF Liberator

USAAF A-29 Hudson

RAF FortressBlimps

Maritime Patrol Aircraft

Caught On The Surface – Robert Taylor

RAF Sunderland Flying Boat – Coastal Command vs. U-461

20 July 1943 – Bay of Biscay

Source

Airborne Detection Tools Leigh Light

Powerful aircraft light for night attacks

Introduced June 1942

Airborne Detection Tools Airborne Radar

Permitted location of submarines in bad weather and at night

First U-boat kill November 1941

RAF Coastal Command Liberator Mk III with ASV radar

Antenna Detail

Pioneering video documentary 1952-53

Going on the Offensive

(0 – 7:04)

Escort Carrier

T-3 Tanker

USS Bogue

Built in Kaiser shipyards on T-3 tanker hulls

Escort Carrier

Comparison With Fleet Carrier

USS BogueCVE-9

Source

Displacement: 7,800 tons standard; 15,700 tons full load (design)Length: 495' 8" (151.1 m) Beam: 111.5'  (34 m)Power plant: 2 boilers (285 psi); 1 steam turbine; 1 shaft; 8,500 shpSpeed: 16.5 knotsArmament: 2 single 5"/51 (later 5"/38) gun mounts; (1943) 8 twin 40-mm/56-cal gun mounts; (1943) 27 single 20-mm/70-cal gun mountsAircraft: 24Aviation facilities: 2 elevators; 1 hydraulic catapultCrew: 890

Laid Down: 1 Oct 41 Launched: 15 Jan 42 Commissioned: 28 Sep 42

Hunter-Killer Team

Hunter Becomes the Hunted

U-118 under attack by aircraft from USS Bogue

June 12, 1943Source

Battle of the Atlantic Won

( 1:48:30 – 1:54:10 )

Capture of U-505

Task Force 22.3

June 4, 1944

Escort carrier Guadalcanal (CVE-60)

Five destroyer escorts:

Pillsbury (DE-133) Pope (DE-134), Flaherty (DE-135), Chatelain (DE-149), Jenks (DE-665)

Captain Dan GalleryCommander

Capture of U-505

( 18:12 – 25:27 )

Capture of U-505

Boarding Party Arrives from USS Pillsbury

June 4, 1944

Capture of U-505

First USN combat prize since War of 1812

Capture of U-505

USS Guadalcanal towing U-505

Players in U-505 Capture

Captain Daniel V. Gallery LT(jg) Albert L. David

Players in U-505 Capture

Captain Daniel V. Gallery

• Commander, Task Group 22.3

• After capture, Navy did not know what to do with him

• Set his sights on capturing a U-boat

• Decorate him

• Court martial him

• Eventually promoted him to rear admiralWhy?

Players in U-505 Capture

LT(jg) Albert L. David

• Asst. Engineering Officer on USS Pillsbury

• Led boarding party to U-505

• Remained inside sub despite threat of scuttling charges & open sea valves

• Awarded Medal of Honor

• Only MOH awarded for Battle of Atlantic

May 1943: The Turning Point

“What is now decisive is that enemy aircraft have been equipped with a new location apparatus … which enables them to detect submarines and attack them in low cloud, bad visibility, or at nights. Much the largest number of submarines now being sunk are being sunk by aircraft. … These losses are too high. We must now husband our resources because, to do anything else, would simply be to play the enemy’s game”

Admiral Dönitz to Hitler, May 1943

U-boat Losses By Month

U-boat.net

Ship Losses 1940 - 1945

Ships Lost vs. Built1939-1945

Source

US Shipbuilding

Source

Ships Built by US Maritime Commission1939-1947

US Maritime Commission

5,500+ ships

Losses

Museum of Science & Industry, Chicago

Victory in the Atlantic

( 25:26 - 26:29)

"The Battle of the Atlantic was the dominating factor all through the war. Never for one moment could we forget that everything happening elsewhere, on land, at sea, in the air, depended ultimately on its outcome.”

Winston S. Churchill,The Second World War, Volume V, Closing the Ring1951

The Second Battle of the Atlantic

“The German people do not understand the sea”

Attributed to Admiral Alfred von Tirpitz (1849-1930)

Lesson 24WW II: America Enters the War

Lesson Objectives

•  Understand the Japanese and American strategies for the war in the Pacific and Asia.

•  Analyze the impact of the military revolution during the interwar years on the war in the Pacific theater.

•  Become familiar with the timeline of events in the Pacific war.

•  Understand the significance of the Battle of Midway and the role of signals intelligence in the outcome.