In today's society, we rely on air travel so much we don't think about it. I use it all the time when I have to get in and out of the village. I still travel on such small planes, the pilot is the one who gives the safety talk as he's getting the small Navajo 6 or 9 seater warmed up for take off.
They use some sort of system which tells them where they are at all times. It gives them headings. Tells them when to turn. Just about everything they need to make it from point A to point B but how did those early planes make it from New York to San Francisco before this technology?
In the early days of air service when the Post Office began flying mail across the country, most airplanes could only fly during the day because there were no street lights, nothing for them to follow. When the post office began air mail, it took 83 hours for a letter to travel from New York City to San Francisco since they could only fly during the day. Once daylight started waning, they landed and the mail was put on trains to travel through the night. When dawn came, the mail was once again transported by plane. The postal service used this hybrid system until they figured out a way to place markers across the country.
Beginning in the mid 1920's, the United States government decided to build a series of light houses on cement arrows to point the direction from the east to the west coasts. Prior to this, pilots had to follow railroad tracks to fly across country but with this system of light houses, they could fly at night instead of off loading the mail to the train. Once the system was finished, it reduced the time to 33 hours for the letter to fly from New York city to San Francisco.
The Transcontinental Airway System was built during the 1920's. Originally the first towers used acetylene gas powered lights fed by fuel kept in the sheds but eventually these were replaced by a 60 foot lighthouse with a revolving motorized light on top standing on a 50 to 70 foot cement arrow that pointed to the next station. Each beacon had a small generator shed with the beacon number based on mileage painted on one side of the roof and the route destination on the other half. Eventually, most of the beacons were built in the west since that was more sparsely populated.
Although the primary white light could be seen from about 10 miles away in good weather, the beacons used a secondary system of red and green lights to flash the Morris code letters as a way of identifying the beacon to the pilots. In addition, the government built several emergency landing fields with lights that could be seen from 75 miles away.
The government built 1,550 light houses across 18,000 miles by the time the system was completed. It made the country feel smaller and safer. The down side to this system was the maintenance cost which included paying for the rented land, paying for someone to keep an eye on the station, the light bulbs, and the mechanical parts. One magazine estimated the cost at $110 per month or about $1500 in today's dollars. Take that cost and multiply it by the number of light houses and you are talking in adjust dollars over 2 million per month to maintain these beacons.
As technology improved, planes soon flew without the need to use visual based systems because of the development of the low frequency radio range system. The government began shutting down beacon system was shut down in 1933 but some continued operating into the 1940's and the very ast ones were shut down in 1973.
So if you ever come across a cement arrow in the middle of nowhere, this is its story from a slice of American History. Let me know what you think. I'd love to hear.
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