World’s Highest-Powered Beacon

Sun (Auckland), Volume II, Issue 412, 21 July 1928, Page 24

World’s HighestPowered Beacon

Visible for 100 Miles from the Air X aviation beacon O! any in the world is now Jn M flashing from the sumId! mit of Mt. Diablo, neat Owing to the fact that the mountain is sorrounded by such vast areas of relatively level land and. with the expanses of the Pacific Ocean to the westward, the placing of a beacon on the summit of Mount Diablo is equivalent to putting one on a tower nearly 4,000 ft high. There is no other place in the world where an airway beacon could be placed more advantageously. Mount Diablo stands virtually at the intersection of the .transcontinental airwa> from San Francisco and Oakland eastward and the airways which traverse ; California north and south. This summer new air mail schedules will provide for night flying and then the | Mount Diablo light will be of inestim- | able value.

The Standard Oil Company of California, at the suggestion of the Department of Commerce, erected the beacon and another of equal power in the Merced hills near Los Angeles. These two beacons are the first of their type and the highest powered incandescent beacons in the country. Each of these beacons develops 10,000,000 candlepower and is visible from the air for between 100 and 150 miles. They are placed on top of 75ft steel towers, and they revolve six times a minute.

The Department of Commerce gave the official symbols “SD” and **SL” to these lights, the former standing for “Standard-Diablo” and the latter signifying “Standard-Los Angeles.” In order to identify the beacons these symbols, in letters 12ft high and illuminated by neon lights hang on the sides of the towers. The reflector and lens of the beacon are 36in in diameter. Immediately in front of the reflector there is a 1.500 watt incandescent lamb, which furnishes the light. Has Automatic Substitute Tlie beacon is equipped with an ingenious device holding two of the incandescent lamps—one directly in front of the focal point of the reflector. In the event of this lamp burning out the second lamp is automatically thrown over to take the place of the one that has gone out. This is done

almost instantly, so that there is no interruption in the operation of the beacon. An automatic astronomical clock turns the beacon on at sunset and off at sunrise. This clock automatically compensates for the constantly changing hours of sunset and sunrise.

These lights complement the existing system of daylight airway signs which the Standard Oil Company maintains at some 500 points on the Pacific Coast. The signs are painted on the roofs of its warehouses and give the name of the town in which located. They can be read by aviators at a height of several thousand feet.