| Date | Text | |
|---|---|---|
14 Oct 1947
Air pollution control district |
Air pollution control district In 1947, the Los Angeles County Board of Supervisors established the first U.S. air pollution control program by creating the L.A. County Air Pollution Control District. It responsed to the serious smog in the city on 26 Jul 1943 when a noxious haze of smoke and exhaust fumes reduced visibility to under three blocks. From Oct 1943, a Smoke and Fumes Commission studied the problem. It named many cause: locomotive smoke, diesel truck fumes, back-yard rubbish burning plus the mountain topography, stagnant winds and atmospheric temperature inversions. On 31 Jul 1954, a six-year research program reported that the smog was caused by the chemical reaction of sunlight on auto and industrial emissions. London's killer Great Smog on 5 Dec 1952, led to the Clean Air Act of 1956. |
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14 Oct 1947
First supersonic flight |
First supersonic flight In 1947, Chuck Yeager, a WW II fighter pilot, became the first human to fly faster than the speed of sound, breaking through the sound barrier in a rocket powered Bell XS-1 airplane over Murac Dry Lake, California. The four rocket motors of this tiny needle-nosed research craft could gulp an entire supply of fuel in 2-1/2 minutes. To save fuel, the Bell XS-1 was carried aloft by a B-29 then released, and Yeager fired its rockets. At 37,000 feet the X-1 flew well, but began to buffet as it approached the sound barrier. When an airplane travels at the speed of sound the air particles ahead are compressed into an invisible “wall of thick air.” Others flying with less powerful engines could not push through this wall, with hazardous and deadly results. Yeager succeeded. |
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