By Stars, Beacons, and Satellites

The lost art-and intimidating science-of aerial navigation.

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(Continued from page 3)

Unlike the NDBs, which pointed a finger, human-like, at the transmitting station (“It’s over there!”), VORs gave you a number, an abstraction that required you to refer to a map to convert the number to a line of position, called a radial. Most aircraft had two VORs, and an exact position could be obtained by the intersection of two radials at a reasonably large angle to each other or, alternatively, by a radial and a distance provided by a radio ranging gadget called distance measuring equipment, or DME.

By the mid-1950s the country was thickly dotted with VOR and DME transmitters—low circular structures, each with a slender truncated cone rising from the center. Dead reckoning sank into disuse, surviving only in questions on the private pilot written test, as pilots came to depend on VORs as stepping stones from one place to another.

VORs made it unnecessary to monitor the wind. With non-directional beacons, if the pilot did not include drift in his heading, a crosswind would push the airplane off track. The automatic direction finder needle would swing progressively to the side as the pilot, continually adjusting his heading, flew an unintentional curved line toward the station. VOR radials are fixed tracks in space; a pilot automatically compensates for wind drift if he merely keeps the OBS needle centered.

One of the unintended side effects of the VOR network was to superimpose upon the familiar map of the United States one that accorded to little-known places like Wink, Texas, or Hector, California, the same familiarity as St. Louis and Indianapolis. It drilled their names into the consciousness of pilots who, droning along, often at night, over a featureless landscape, fastened their attention upon, for lack of anything better, a Morse code identifier and a faint, scratchy tenor intoning, over and over, “Wink...VOR...”

I Once Was Lost, But Now Am Found
Each advance in navigational technique brought an improvement in accuracy, reliability, or ease of use. Each was in one way or another a simplification, but it also required new learning and new insights from its users. And then came GPS, the satellite-based system, originally intended for military tracking and targeting, that identified the location of anything on or near Earth within a few feet.

GPS changed everything. It was GPS—or rather the boundless varieties of digital processing of raw GPS data—that brought navigation to maturity, and the great historical traditions of navigation to their knees. A drug irresistible to even the fiercest Luddite, GPS at one infantalizes and deifies us. With GPS there are no landmarks, no beacons, no airways, except as relics of earlier times. There is only the surface of the planet. GPS makes skill, intuition, and judgment unnecessary. Navigation, that great and noble art, whose traditions reach back into the darkness of prehistory, has degenerated into a computer game. Orientation, sense of direction, dead reckoning, line of position, pilotage, weather sense, drift, heading, track, course, VOR, NDB, precession, magnetic variation, estimation, latitude, longitude, azimuth, elevation, lost, found—relics all.


Sidebar: Where the Beacons Beckon

“There it is!”

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