The dusty landscape of the American West is dotted with enormous concrete arrows. They look like cryptic messages from a primitive civilization — a civilization that was obsessed with westward expansion. And that assessment wouldn't be altogether wrong. But these enormous arrows pointing west tell only part of the story. Because at the dawn of aviation, they were part of America's highway of light — a high-tech system of lighthouses showing pilots how to get from New York City all the way to San Francisco.
"[Airmail is an] impractical sort of fad and has no place in the serious job of postal transportation." - Second Assistant U.S. Postmaster General Paul Henderson in 1922
When the U.S. Postal Service opened up airmail routes during the early 1920s, many people saw it as a frivolous novelty. What good was sending mail by air? Sure, planes could travel faster than trains. But airplanes could only operate safely during the daytime, whereas trains could run all night.
As a result, early transcontinental airmail delivery was a hybrid system. In 1922, letters sent by airmail would have to leapfrog the country, traveling by air during the day and by train at night. Using this process, a letter moving at its absolute fastest might take about 83 hours to get from New York to San Francisco.
The few pilots who did try to travel at night during this time were taking their lives in their hands. Nearly 1 in 10 early airmail pilots died during the early days of the postal service's airmail initiative, and emergency landings were common. There had to be a safer way.
Enter the highway of light — a system of airmail beacons that spanned the country.
Built by the U.S. government, the airmail beacons of the mid-1920s helped pilots find their way much more safely — whether it was day or night. Spaced out every few miles, from New York to San Francisco, each site consisted of a revolving motor-driven light which sat at the top of a 60-foot tower. The 1931 illustration above from the FAA archives shows how the light tower sat in between a concrete arrow on the ground and a building that contained a generator, which powered the entire thing.
Originally approved by Congress in 1921, the light beacon system was planned to cross the entire United States by mid-decade. Unfortunately, President Warren G. Harding slashed funding and the issue wouldn't gain steam again until the mid-1920s.
Previously, the most reliable method of navigation for pilots was to use their old fashioned rivals as a guide; following the railroad routes ensured that they were staying on track. But this new system of towers — inland lighthouses with gigantic concrete arrows pointing the way — allowed air pilots to navigate without depending solely on yesterday's infrastructure.
Once the new lighted airway was in place, that same letter that used to take 83 hours took just 33 hours to get from New York to San Francisco. By 1926, the Transcontinental Airway System's light beacons were brought under the authority of the Bureau of Lighthouses and crossing the country by air (day or night) was considered much safer.