America's Concrete Arrows Guided Early Airmail Pilots
🕓 Estimated Reading Time: 5 minutes Overview In the vast expanse of the American landscape, remnants of a forgotten era lie scattered, silent testaments to human ingenuity and the dawn of commercial aviation. These are the colossal concrete arrows , massive ground markers strategically placed across the continental United States almost a century ago. Before the advent of advanced radio navigation systems, these physical pointers served as indispensable guides for pioneering airmail pilots , enabling them to navigate rudimentary air routes and deliver mail with unprecedented speed. Their story is a captivating chapter in the broader narrative of American innovation and the relentless pursuit of progress in the skies, often overlooked in modern discussions of flight. From the initial experimental flights of the early 20th century to the establishment of regular airmail service, the challenge of reliable aerial navigation was paramount. Pilots often flew by 'dead reckoning' or fo...