A GREAT AIRSHIP

Dominion, Volume 18, Issue 149, 18 March 1924, Page 8

A GREAT AIRSHIP

THE SHENANDOAH. Floating majestically overhead, its silver sides gleaming against a blue white sky, tlio Shenandoah or ZR —1, sailed recently over several Eastern cities of America on its maiden voyage. Quite appropriately, it was christened “Daughter of the Stars,” for that is the Indian meaning of the word “Shenandoah.” This giant dirigible foretells an ora of transportation which, by comparison, will make the wildest dreams of years ago, commonplace. Tho Shenandoah was built at Lakehurst, N.J., by the United States Navy. It is 680 feet Idug, 7S feet in diameter, and from the bottom of its cars to tho top of tho bag, it is 96 feet. It is powered by six 300 horse-power specially-built Packard motors (1800 h.p. in all), which, it if> estimated, will give the huge craft a speed of 70 miles an hour. Its 5000 gallons of fuel is carried in tanks placed along a centre keel compart ment. The cruising range is over 4000 miles. Instead of hydrogen, which has been used as tho supporting gas for dirigibles and all other lighter-than-air craft for many years past, helium gas has been used to inflate the Shenandoah. Helium gas forms 1 per cent, to 3 per cent, certain natural gases found in the Texas and Kansas oil fields. Of this valuable gas 2,150,000 cubic feet are needed to fill the bag of the Shenandoah. Though nearly as buoyant, it has not the explosive qualities of the hydrogen gas. Contrary to the general belief, the Shenandoah’s gas is enclosed in twenty gas cells within tho outer covering, and not in one bag. These individual gas cells were made from the intestines of nearly a million cattle. Tho sole purpose of the outer covering is to give tho ship u stream-line effect and to protect the interior gas cells from the sun’s rays and from rain and snow. Tho metal framework is made of duralumin, a metal compound of aluminium, copper, and manganese. It is as strong as mild steel, weighs only one-third as much, but its cost is about fifty times greater. In the outside cars are contained the six engines. Tho forward car is called tho control car, and, in addition to containing its engine, it is to tho airship what tho bridge is to the battle"hip. It contains the lilt controls, steering controls, telegraphs, radio, gyroscopic and magnetic compasses, etc., and is the point from which the ship will be steered, piloted, and navigated in the air. Special 12-volt exido batteries are used to furnish cm rent for engine ignition and running lights. These batteries in order to combine high capacity with light-weight, ’have very thin plates, assembled in hard rubber containers. One battery is located in each of the six engine cars. For radio, where tho demand for current may require 200 amperes or more for a few minutes, four Exido batteries of the canio type as used for ignition and running light are used in seriesparalleled on a 24-volt circuit. The series-parallel arrangement was adopted instead of using larger batteries, in order to insure absolute interchangeability of nil batteries on the ship. The radio batteries are located, together with all the radio equipments', in the control car. All the batteries receive their charge from a generator system m much the .same manner as an automobile starting and lighting battery receives its charge. Tho huge building in which the Shenandoah is housed cost approximately 2,001),1)00 dollars. Ir, is 962 feet long, 3IS feet wide, and 200 feet high. Tho clear door opening is 258 foot wide.