THE NORGE.

Hawera Star, Volume XLVI, 19 April 1926, Page 10

THE NORGE.

AMUN D,SEN’S AIRSHIP DESCRIBED.

The Norge is the first of a. series of Italian semi-rigid dirigibles, dpsigned and constructed 'by Colonel Nobile, iit which tlip aerodynamic characteristics of rigid dirigibles are obtained without sacrificing the advantages ol the non-rigid types. The semirigid dirigibles are composed merely of a backbone or keel of steel tubing, above which an envelope containing liy. drogen is attached, while the pilots and engine cabins hang below. The envelope is flexible and only maintains -its shape through the pressure of the hydrogen inside. This lessens the danger of buckling in storms. Destined to fly in the Polar regions, the Norge has undergone some adaptions to render it more suitable for this difficult flight. Such ail enterprise presents two chief difficulties — the severity of the climate and the necessity to alight on the sea with the aid only of tlie means on board. The length of the journey cannot be considered a technical difficulty, as the dirigible can fly just as long as the fuel supplying the engines lasts. If it can can v •sufficient fuel it can .undertake the flight. Otherwise it cannot. Tlie problem depends on tlie excellence of tlie design of the dirigible, which must be made as light as possible without compromising its strength and size.

The Norge carries 30 tanks for fuel, each containing 67 gallons, the tanks alone weighing only mi trifle over 1100 pounds. The total contents of the fuel tanks are 2000 gallons. or 13,000 pounds. Another 400 pounds of fuel is carried in tins. AVith this amount of fuel the dirigible can travel 65 hours at a. speed of 50 miles, covering a distance is well over 3000 miles, while Lie distance from Spitzbergen to Alaska is less than 2000 miles. There is no water ballast. The kind of ballast, which is used chiefly in landing, can in extreme eases be replaced by fuel in tins carried in the pilot’s cabin. Even if the' hydrogen esc a jies from the envelope, the dirigible tends to rise continually, owing to the decreased weight* corresponding .to the fuel consumed, consequently it is possible to do without ballast

The envelope of the dirigible is made of very strong three-ply rubberised fabric. * The keel is of steel tubing of great strength. The front part of the keel carries a shield-shaped structure, the purpose of which is to resist aerodynamic pressure on the envelope. The rear end of the keel supports a system of rings, which in turn carry the appendages and the rudder in such a way that the proper functionings of the triplane and rudder is independent of the pressure of gas on the envelope. The pilot’s cabin is small in size, though comprising a. comfortable navigating room and radio station, and possessing great visibility in all directions. From the pilot’s cabin it is possible to see the entire length of the keel, and even to pass into it. The whole length of the keel, from prow to stern; may be travelled on an extremely light corrugated duck walk resting on the lower steel 1 tube of the keel, which is divided in'- two over the pilot’s cabin. At the prow of the dirigible an extremely light duraluminum ladder permits access to the air valves and tlie top of the envelope Inside the keel are the thirty fuel tanks, with very light suspensions. Two longitudinal copper tubes collect the. gasoline from right to left tanks and lead it to the engine cabins. It is possible to transfer fuel from one tank to another in order to insure perfect equilibrium in.the dirigible under all conditions.

There are three engine cabins, two lateral and one at tlie stern in the centre. They are suspended with steel cables from the keel. They each have room for one motorman, who is well protected from the wind. Each engine, is fitted with a central radiator, which may be exposed in varying degree to the wind by means of shutters, and two lateral radiators, which' can lie removed.

These dismountable radiators aye necessary in a temperate climate, but in the polar regions . are superfluous and can be left behind. The engine in the stern cabin is equipped with a device lor inverting the propeller. Oil tanks are in the engine cabins, with double walls and intermediate felt insulation to (prevent the oil from freezing

Another difficulty, mentioned before, is landing or alighting on the sea with only the means available on board. The great difficulty is to find a way to attach a cable to the earth oi) ice wherewith to pull the dirigible down. For alighting on the sea a great sack has been made, which, when thrown into the sea and filled with water, pulls the dirigible down. As the dirigible must travel over regions covered with ice, a special anchor in the shape of a projectile also has been made. This anchor, dropped from the dirigible, penetrates the ice by the force, acquired during tlie fall. .When tlie cable to .which it is attached is pulled from the dirigible, steel points shoot .out from the sides of the anchor, holding it firmly to the ice. The cables attached to the sack for alighting on the sea; and the anchor for landing are passed over a pulley in the keel to a hand operated winch. The iiroiv of the dirigible lias been slightly modified to make mooring at a mast possible. One such mast has been specially built at station No. 2 in Nor wav.