Our First Scouting Dirigibles 



We have copied the British "Blimps." 

 Here the construction is explained 



WHEN German submarines began to 

 render even the high seas danger- 

 ous to shipping, England found 

 herself in a very perilous position. To 

 patrol the waters around England by 

 small craft was the immediate remedy 

 adopted. But the area to be covered 

 was so vast that literally thousands of 

 vessels would have been required. Air- 

 planes were out of the question because 

 they lacked the necessary endurance and 

 because of the demands made on the pilot. 

 It was clear that airships might answer, but 

 England had only very small ones, slow 



flying and very unhandy for the purpose. 

 Some unknown genius hit upon the 

 "Blimp" as a solution of the problem. 

 England was building airplane bodies, or 

 fuselages, as they are called, by the thou- 

 sands — building them as we build auto- 

 mobiles in this country. She was also 

 producing hundreds of gas envelopes. 

 Why not suspend an airplane fuselage from 

 a gasbag? The question was brilliantly 

 answered by the "Blimp." 



Envelope inflated with 

 hydrogen gas 



Air filled 

 balloneV 



Ballonet 

 suspension 



Water trimming 1 

 tank. \ \ 



The gas envelope is much like that of other non- 

 rigid dirigibles. As the vessel rises the gas expands 

 and some of it escapes through a safety valve to 

 prevent bursting. To preserve the shape when 

 the gas contracts, ballonets are used, one in front 

 and one in the rear, as explained on next page 



Kapok floats 



Blower 

 intake 



The Forty-Five-Mile-An-Hour "Blimp" Which Was Considered a Makeshift in the 



The gasbag is 160 feet long and 31 H feet in diameter, 

 with a capacity of 77,000 cubic feet of gas. There is 

 a standard 100-HP motor provided with duplicate 

 controls so that the two passengers can run the ship 

 alternately. Wheels are not needed under the car or 



fuselage. Even with more load than the gas can lift 

 the vessel can be made to rise easily without a pre- 

 liminary run on the ground, simply by pointing the 

 nose up (through air trimming) and letting the propeller 

 exert an upward thrust. The chief difficulty with all 



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