Old Before She Was Launched 



There are styles in airships as well as in derby hats. The 

 D. N. 1, our new navy schoolship-dirigible, is new and yet so old 



TWO years ago, the United States Navy 

 contracted for a small dirigible 

 to serve as a schoolship. Now that the 

 craft has been finished, now that it can 

 be judged in the light of the European war, 

 it must be wholeheartedly 

 condemned as well-nigh 

 useless. 



Thedesignersof 

 the D. N. 1 were 

 not daringly original. 

 They simply copied an 

 Austrian airship, the 

 Koerting, destroyed short- 

 ly before the war in a 

 collision with an airplane. 

 A few fea- 

 tures of some 

 utterly use- 

 less British 

 airships (des- 

 ignated by 

 Greek letters 



Alpha, Beta, *ggg 



etc.) were in- 

 corporated . 



In the 

 Koerting, the 

 car was elon- 

 gated fore 

 and aft to receive front and rear suspension 

 ropes. Thus the strain on the tender gas 

 envelope was lessened. In the D. N. 1 that 

 system of suspension is copied. The 

 Koerting had two motors so that it was 

 safeguarded to a certain extent against 

 breakdowns; but the D. N. 1 must make 

 the best of a single motor. The two pro- 

 pellers of the D. N. 1 are driven by bevel 

 gearing, the arrangement being such that 

 they can be swiveled. Hence, the craft 

 can be pushed up or down by its propellers 

 while it is making very little headway — a 

 decided advantage in landing and starting. 

 The D.N.I can be tethered by the nose of 

 the gas envelope to a tall mast so as to 

 ride out storms — a good idea because the 

 ropes distribute the strain evenly over 

 the envelope. 



The Koerting was never regarded in 

 Europe as a model to be followed. The 

 D. N. 1 is worse than the Koerting. Its fuel 

 capacity is sufficient only for two hours 



© Int. Film Serv. 



The D.N. 1, the navy schoolship-dirigible, is 175 feet 

 long. It has a 140-HP engine to drive it at a speed of 25 

 miles an hour. Although new it is hopelessly antiquated 



so that it may carry an apprentice crew of 

 seven. Three or four apprentices would 

 have been a more reasonable number. 



The whole idea of the D. N. 1 is funda- 

 mentally wrong. There may be some justi- 

 fication in degrading an old diri- 

 gible, which has seen active 

 service, to the level of a 

 schoolship, but there 

 seems no excuse- for 

 designing an en- 

 tirely new dirigible 

 which is so slow 

 that the experience 

 to be gained in it is 

 not even remotely 

 similar to that re- 

 quired of the 

 men in full- 

 sized fast 

 militaryorna- 

 val airships. 

 An air- 

 plane has 

 what is called 

 dynamic lift; 

 that is, it 

 rises by vir- 

 tue of its own 

 fast motion. 

 A dirigible, too, has dynamic lift when it is 

 fast. A slow dirigible has little or no dyna- 

 mic lift. The whole science of piloting a 

 dirigible is founded on the proper utilization 

 of dynamic lift — a fact which we have 

 learned in this country although the ex- 

 tensive German literature on the subject 

 has harped on it constantly. In a dirigible 

 of twenty-five miles an hour (the speed of 

 the D. N. 1) little more can be learned than 

 in an ordinary spherical balloon. 



The faster the dirigible, the safer will 

 it prove to be for an apprentice. Its 

 dynamic lift makes it easy to overcome 

 mistakes in managing gas and ballast. 

 Moreover, a fast dirigible is not easily 

 forced to land; and an enforced landing 

 is the worst danger because no dirigible 

 can come down anywhere in safety like 

 a spherical balloon. Even the English Alpha, 

 Beta, and Gamma ships have been discarded 

 in favor of the " Blimps." — small dirigibles 

 whose cars are wingless airplane bodies. 



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