The Akron, the Airship of the United States Navy

Abstract

IN the new airship Akron built for the United States Navy there are incorporated several improvements which set new standards of efficiency for subsequent lighter-than-air machines. The ship is larger than most ocean liners and, unlike most of its predecessors, it is largely actuated by electricity and electrical apparatus. Particulars of the ship are given in the Westinghouse International for the first quarter of 1932. The power plant consists of two petrol-driven 11-kilowatt generators, with a motor generator set for battery charging. The total weight allowed for the electrical system on board was only 3000 Ib. Aluminium alloys were largely used for the machines and cables, and all the circuits are controlled from the generator room. The radio system takes the heaviest load from the generators. The antenna system consists of two trailing antennse and a fixed wire antenna. The latter is used for landing manoeuvres and for auxiliary purposes. Fire risk is practically eliminated, the twelve supporting gasbags of the ship being filled with helium; but even if they had been filled with hydrogen there would have been little risk of explosion, as every power outlet on the ship is so constructed that the plug cannot be removed or inserted unless its switch is in the ‘off’ position. Miniature lightning arresters protect the ship from static charges of electricity picked up while the ship is in flight, especially when she changes from one equipotential surface of the earth's electric field to the other. These arresters also drain off any electrostatic charges that might be induced by the ship's radio. The telephone system has seventeen telephones, the switchboard on which the keys and lamps are mounted weighing only thirty pounds. A special feature of the Akron is the powerful searchlight which is used for signalling and for landing. It consists of a 500-watt lamp with a fourteen-inch reflector. In daylight tests its light is brilliantly visible at a distance of four miles.