NO. 3 EUROPEAN AERONAUTICAL LABORATORIES ZAHM II 



dollars per year and to employ 700 men, 400 of them working- on 

 aeroplanes. It has facilities for producing daily one complete 

 aeroplane, excepting the engine, which at present is bought elsewhere. 

 Its air craft are systematically tested on the great flying field nearby, 

 bearing instruments which reveal their complete working in practi- 

 cal maneuver. ( )ne instrument alone, called the " ripograph,"" records 

 simultaneously the angles of pitch, roll and yaw, the speed through 

 air, the altitude, the three control movements and the time. The 

 stress in the wires, the i)ropeller thrust and the pressure distribution 

 on the wings and other surfaces may likewise be recorded.* The 

 establishment does in fact the work j)lanned in the United States 

 for both the field laboratory and the exj)erimental air craft factory. 

 But the Royal Air Craft Factory lacks some of the facilities planned 

 for our plant, such as an expanse of water for testing naval aero- 

 planes, and the immediate accessibility of allied laboratories, work- 

 shops and other resources. 



The result of the full-scale experiments has been to disclose the 

 defects of the leading types of aeroplanes, and to indicate means of 

 betterment. Substantial improvement has been made in the efficiency, 

 stability, factor of safety and range of speed of the aeroplanes 

 specially studied at the factory. The final outcome has been to pro- 

 duce a stable, efiicient and safe biplane having a range of speed of 

 40 to 80 miles an hour. It is expected shortly that a standard control 

 will be adopted after the best types have been given a comparative 

 test. The type at jjresent most in favor is the Deperdussin control, 

 which rotates a wheel for warping, shoves it for elevating, and 

 uses a foot lever for steering. Such practical full-scale work cannot 

 be too strongly recommended for the Smithsonian Institution, es- 

 pecially if the army and navy will, as already intimated, furnish for 

 such tests their typical air craft and their experienced pilots. 



Reports. — The scope and character of the activities of both the 

 factory and the laboratory can best be gathered from the annual 

 reports of the Advisory Committee. These set forth all the work 

 initiated by the committee, including, besides reports of experiments, 

 all the theoretical researches, and all the summaries made by its 

 members, in any form, whether of elaborate memoirs, translations 

 or abstracts. The catholic character of these reports is praiseworthy, 

 but their literary form and editing could well be improved. In this 

 latter respect Eififel's reports form more elegant models. 



' All these measuring and recording devices can be purchased from the Cam- 

 bridge Scientific Instrument Co. 



