The Secret War

World Wars: World War II

1933—Albert Einstein—the World’s leading physicist—flees Europe for America.January 1939—German physicist Otto Hahn

achieves 1st stage of nuclear fission.The first step in the creation of an atomic bomb.

NAZI Atomic Development

August 2, 1939—Leo Szilard and Einstein write FDR warning him about the power of an atomic bomb.A year later FDR sets up

a board of scientists to study the possibility of creating an atomic weapon.

U.S. Atomic Development

August 1939—Germans set up a board of scientists to study the atomic weapon.They were the best in the world despite losing

many great Jewish scientists to immigration.Hitler didn’t fund the program heavily.

U.S. Atomic Development

Hitler felt the War would be over before an atomic bomb was made.Hitler concentrated on funding for the rocket

program.

U.S. Atomic Development

Neither side was sure if a bomb were created, that it would even work.The cost was high

for no assurance of success.

U.S. Atomic Development

May 1941—FDR creates the Office of Scientific Research and Development.Headed by Vannevar Bush—13 months later

goes ahead with bomb project.

U.S. Atomic Development

Two months later the Manhattan Engineering District was established.Headed by brigadier General Leslie R. Groves.

U.S. Atomic Development

Immediately Groves acquired all of the world’s uranium which was need for the project.Uranium 235—fissionable

part of uranium need for the explosion.

Groves selected Physicist J. Robert Oppenheimer as scientific director.

Leslie Groves with Oppenheimer

U.S. Atomic Development

Germans created the bomb first but had no uraniumInstead Hitler decided to focus on the creation

of rockets. “V” Weapons (Vengeance)

V-1 Rocket V-2 Rocket

German Work Toward the Bomb

Project was headed by German scientist Werner Von Braun.The German scientists were way ahead of the

world in rocket research.

German Work Toward the Bomb

Germans created the first intermediate range ballistic missile the V-1Followed this up with the deadlier V-2—

liquid fueled with a 1 ton warhead.8,000 are launched

against Britain but only 1/5 of those hit any targets.

More a weapon of terror due to the inconsistent guidance controls.

German Work Toward the Bomb

The V-1 and V-2 rockets killed 2,500 civilians and injured 30,000 more in England.

German Work Toward the Bomb

The Germans also created the world’s first jet aircraft—the Me 262.Due to Hitler’s obsession with bombing London

—the Me 262 came to late.If used in 1944—the Me262 would have made a

dramatic difference.

German Work Toward the Bomb

British created one of the world’s first computers that helped decode German encryption.Gave the Allies valuable information which

helped in the fight against the Nazis Enigma Code Breaker

The same system was used in the Pacific providing valuable information about Japanese plans.

British Computer Development

Device created that used radio beams which reflect off planes, subs, ships, etc. Bounced back to the sender to reveal an object.

Radar—Radio Detection and Ranging

Used most effectively by the British (won the Battle of Britain)—and then the U.S.

Axis radar was never up to the standards, and the Japanese radar was very poor.

Radar—Radio Detection and Ranging

The proximity fuse was an explosive shell which detonated near or on a target.Used in fighter planes, and with

artillery shells.Greatly increased effectiveness

for the Allies.

Proximity Fuse

The Norden Bombsight—was an optical device that used automatic pilot for precision bombing.Was pinpoint accurate when clear, a little less

effective in overcast conditions.

Norden Bombsight

The Allies also introduced—Jet Aircraft, atomic bombs, ballistic missiles, and the hand held rocket (Bazookas)

Norden Bombsight

Made for much more efficient killing during the war.After the war, these inventions would lead to

spin-offs in science and technology.

Impact of New Technology

Albert Einstein Otto HahnLeo Slizard Office of Scientific Leslie Groves Research and

DevelopmentThe Manhattan Project J. Robert

OppenheimerUranium 235 “V” weaponsWerner Von Braun V-1V-2 Me 262RADAR Proximity FuseNorden Bombsight

Terms, Names, Events