November 26, 2013 Pointing the way

The Liberty Gazette

November 26, 2913

Ely Air Lines
By Mike Ely and Linda Street-Ely

Mike: Hunkered down in his open cockpit the aviator is wrapped in a heavy jumpsuit, fleece-lined leather jacket and helmet, goggles, and a silk scarf tied securely around his neck for wiping engine oil from his goggles. He peers out into the nighttime blizzard looking for a farmer’s bonfire. Once he sees it he continues on looking for the next as he crosses the countryside flying the U.S. Mail.

Linda: Early methods of air navigation included following railroads, using road maps and looking for easily identifiable objects on the ground, even farmers’ bonfires, in this method known as pilotage. Barns and water tanks that had a town name with an arrow painted on them proved helpful in regaining one’s bearings. Another system of early air navigation relied on a compass and watch. Flight planning for a particular heading at a specific speed for a certain amount of time results in a predictable flight even without fancy equipment. In the first days of airmail cockpits were unlit so reading instruments was difficult, and locating ground markers in the dark not so easy either. Most flying was done in the daytime.

Experimenting with bonfires in 1920 and then beacons in 1923 proved to the U.S. Mail service that it was possible to fly successfully at night along preplanned routes, even in marginal weather. This made operating mail routes with airplanes more efficient than trains, prompting Congress to fund a navigation system using beacons to light the way across the nation. Mail planes were served by an arrangement of beacons mounted on towers every ten miles to cross the nation’s midsection. Four years after construction of the beacons began the Federal Airway system was turned over to the Commerce Department’s Bureau of Lighthouses, the obvious choice for people with experience creating safe travel in the dark. Within 10 years 1,550 beacons covered 18,000 miles.

Mike: Often placed at remote locations each beacon site was built upon a concrete foundation in the form of an arrow pointing in the direction of the next beacon site. Mounted on the arrow was a tower that housed the rotating beacon. At the feather end of the concrete arrow was a shack protecting two generators; if one failed the other would continue on – pilots like redundancy. The beacons’ automatic bulb changing system swung a spare bulb into place when the other burned out. If a pilot had to land to wait out inclement weather or deal with a mechanical problem, the beacons were a welcome sight during those dark nights; their flashing green or red light signaling whether there was an adjacent landing strip. Many of the arrows still exist.

Ground-based navigation aids evolved over the years and the jump to GPS (satellite based navigation) equipment began offering precision positioning, but there are those who still use good old-fashioned pilotage as a preferred form of navigation. The Montana State Department of Aeronautics operates 17 of those original beacons to help pilots travel through the mountain passes that can be confusing and disorienting, even with GPS.

Who knows, maybe good old-fashioned pilotage would have been more helpful to the pilots of the 747 that landed at the wrong airport last week – using GPS. Oops.

www.ElyAirLines.blogspot.com