CHAPTER XII 

 FIELD-TRIALS IN 1903 



The extended series of shop tests which had occupied a considerable por- 

 tion of the late winter and early spring of 1903 had demonstrated the following 

 facts: First, with the aerodrome mounted on the launching car, a propeller 

 thrust of from 450 to 475 pounds could he maintained indefinitely by the en- 

 gine, and even when the engine was delivering its full power to the propellers, 

 the vibration was so small as to cause no apprehension that the wings ami rud- 

 der would be made to vibrate sufficiently to produce undue strains in them. 

 Second, with the aerodrome suspended from the ceiling by springs at the points 

 at which the wings would be attached, the vibration produced by the engine de- 

 veloping its full power was even less than when the machine was mounted on 

 the launching car, and there was, consequently, even less cause for concern that 

 the wings and rudder might be set in vibration when the machine was free in 

 the air. Third, the engine could be depended upon to deliver something over 

 52 horse-power when the five cylinders were working properly, and even with 

 one cylinder not working, but acting as a dead load against the others, approx- 

 imately 35 horse-power could be developed, while with two cylinders not work- 

 ing at all, the three which were working would deliver about 25 horse-power. 

 Therefore, even assuming that two of the five cylinders misjht become deranged 

 during a flight, there should still be sufficient power to propel the machine. 

 These tests, some of which had been witnessed by members of the Board of 

 Ordnance and Fortification, clearly demonstrated that the time had arrived when 

 it was safe to give the aerodrome a test in free flight. The machine itself, to- 

 gether with all its appurtenances and much extra material for repairs in case 

 of breakages, which previous experience had shown to be almost certain, was 

 accordingly taken from the shop and placed on the house-boat preparatory to 

 taking it down the river to the point opposite Widewater, Va., which had al- 

 ready been selected as the " experimental ground." 



Owing to the limited size of the shops it had been impossible to place the 

 wings and rudder in their proper positions on the aerodrome and determine its 

 balancing in a way similar to that practiced with the models. The approximate 

 settings for the wings and rudder had, however, been determined by calcula- 

 tion from the data obtained in the test of the quarter-size model, so that it re 

 mained onlv to place the wings and a weight to represent the rudder actually 

 on the machine in the large space of the house-boat (which, however, was not 

 large enough to permit the rudder to be assembled along with the wings), and 

 thus check the balancing previously determined by calculation. There were very 



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