Image from the National Museum of the United States Air Force, Dayton, Ohio via https://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=1591 .
“The lead-up to World War 2 for the United States saw a period of constant progression for its bomber force… [The B-23] prototype went airborne for the first time on July 27th, 1939 – just months ahead of the official start of World War 2 in Europe (September 1st). Serial production was begun that same month and ended in September of 1940 with all 38 aircraft completed.
“By the time of the American entry into the war [in 1941], the B-23 had already met its performance match as newer, better medium types were taken into USAAC service. As such, the B-23 was never seen as an active combat performer during the war but instead relegated for service use as a trainer, stateside maritime patrol, and transport.”
Excerpt from https://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=1591 .
“The maiden flight of the B-23 took place from Clover Field at Santa Monica on July 27, 1939. After being evaluated by the Materiel Division at Wright Field in Ohio, the B-23 entered service with the 89th Reconnaissance Squadron based at March Field in California.”
Excerpt from http://www.joebaugher.com/usaf_bombers/b23.html .
On this date in 1939 Igor Sikorsky piloted the first successful helicopter which he also designed. While he was a pioneer in vertical flight he was not the inventor of the helicopter. However, his improvements of a single lift rotor and a tail rotor made the craft controllable. This prototype led to the first production helicopter.
Although this test occurred in Connecticut, it influenced flight around the world.
See more at http://inventors.about.com/od/hstartinventions/a/helicopter.htm
National Aviation Day, August 19, celebrates the development of aviation.
“The holiday was established in 1939 by Franklin Delano Roosevelt, who issued a presidential proclamation which designated the anniversary of Orville Wright’s birthday to be National Aviation Day (Mr. Wright, born in 1871, was still alive when the proclamation was first issued, and would live another nine years). The proclamation was codified (USC 36:I:A:1:118), and it allows the sitting US President to proclaim August 19 as National Aviation Day each year, if desired. Their proclamation may direct all federal buildings and installations to fly the US flag on that day, and may encourage citizens to observe the day with activities that promote interest in aviation.”
Excerpt from https://en.wikipedia.org/wiki/National_Aviation_Day .
Image retouched from August 1939 Popular Science magazine article on a Los Angeles model airport: https://books.google.com/books?id=yCwDAAAAMBAJ&lpg=PA112&hl=ru&pg=PA112#v=onepage&q&f=false .
1939 activities honoring Wilbur and Orville Wright can be seen here: http://www.centennialofflight.net/chrono/1939.htm . None were in southern California, though.
Image: 1939 postcard.
Learn more about the Burbank airport in the Thirties at http://wesclark.com/burbank/batchelor.html . See a color Trans World Airways 1939 map and company information at https://mappingmovement.newberry.org/selection/twa-airway-map-1939 .