If WWII is such a turning point for technology, how far had technology gotten before the war?

• communications had taken off--particularly radio broadcasting
• The automobile has become the dominant form of transportation
• intercontinental shipping became relatively quick and cheap
• beginnings of drugs that could cure--sulfa drugs
• people much more lived in cities, worked in offices or factories women had new job opportunities, new household technologies
• big businesses increasingly dominate
• development of consumer society
• people saw technology changing the world rapidly
• rise of modernism

pencil sharpener by Raymond Loewy, 1933
 

World War II started in 1939, the US entered in the fall of 1941

• it grew out of the desperate economic situation and finally provided an end to the depression
• scientists and engineers were eager to put their skill to work and the military moved more quickly this time, organizing a National Defense Research Committee in 1940
• the NDRC concentrated on placing contracts at universities, not building new research centers
• In May 1941 NDRC changed its name to the Office of Scientific Research and Development
• sponsored many important wartime research projects

 radar set on airplane

• radar research had begun in the 1930s after some scientifists had observed reflections of radio waves from objects
• by 1937 the British had a continuous chain of stations but these used long waves and required two large antennas
• N. L. Oliphant invented the resonant cavity magnetron, first tube capable of sufficient power for radar at wavelengths less than 50 cm (therefore allowing much smaller antennas and also more accurate results)
• this new idea was brought to the US in 1940 and a major research effort started to develop microwave radar
• the Radiation Lab at MIT designed 150 different radar systems--three generations of systems went into use before the war ended
• invented a junction box to transmit and receive from the same antenna
• invented Loran--a way to determine your location by triangulating from special radio signals
• developed the Microwave Early Warning system with a range of 200 miles
• the Radio Lab at Harvard worked on radar countermeasures--jamming, straw

 antiaircraft fire

• in 1940 anti-aircraft fire using timed fused brought down one plane per 2500 rounds fired
• you need the shell to explode even without a direct hit
• many possible technological approaches for detecting when the shell is close to the airplane--radar, sonar, passive acoustic, photelectric...
• very hard to detect anything from a shell not just moving rapidly through the air but also spinning at 475 RPS.  During development it was jokingly called "the world's most complicated form of self-detroying ammunition"
• radar seemed like the best bet, but how to make a device with vacuum tubes that would fit in a space the size of an icecream cone and survive a force of 20,000 g when fired?
• at one point scientists were dropping tubes from the roof of a 3 story building onto a concrete driveway to test their impact resistance
• development went amazingly fast: pilot production started in Nov. 1941, simulated combat tests in Aug. 1942, in use by Jan. 1943
• mass production of 2 million fuses reduced the cost to $16-23
• results: 6 times more effective than timed fuses

• sulfa drugs developed in 1932 were the first antibiotics, but effective only against one class of bacteria
• Penicillin was discovered by Alexander Fleming in 1929 but no one could figure out how to produce it
• in 1939 two British scientists, Howard Florey and Ernest Chain, figured out how to produce a stable preparation and showed its value (treating 5 patients)
• the US was asked in the summer of 1941 to develop mass production
• seen as of tremendous military value
• factory production began in Dec. 1943, though it was restricted to military use until March 1945