AIRCRAFT PROPULSION — TAYLOR 253 



in use for aircraft engines from tlie beginning, has just recently 

 come into use for some automobiles. After being in England for a 

 number of years, No. 1 Wright engine is now on display in the origi- 

 nal airplane in the National Air Museum, Smithsonian Institution. 

 It was my good fortune to know Orville Wright, and to see him 

 frequently during the period 1919 to 1923 when I was engineer-in- 

 charge of the aircraft-engine laboratory of the U.S. Army Air Serv- 

 ice in Dayton, Ohio. He had previously retired from active 

 participation in aeronautics, and had become a very modest, very 

 quiet, much beloved member of the Dayton community, and of the 

 famous Dayton Engineers Club. 



THE 19 03 MANLY ENGLNE 



Considering the then state of the art, this 52-hp. 5-cylinder water- 

 cooled radial engine represents one of the most remarkable pieces of 

 engineering design and construction ever achieved. Manly, a young 

 graduate of Cornell University, was hired by S. P. Langley, to super- 

 vise the design and construction of his "aerodromes" and to pilot the 

 1903 machine. 



The history of this engine is interesting. In December 1898 Langley 

 contracted with a New York City automobile builder, Stephen M. 

 Balzer, for a 12-hp. engine to be completed in 3 months. Consider- 

 ing that even now, the development of a reliable gasoline engine is a 

 matter of at least 2 years, this contract must stand as one of the 

 most optimistic on record ! 



In May 1900 Manly worked with the Balzer engine, a rotary radial, 

 and came to the conclusion that it was, to say the least, unpromising. 

 At this point Langley and Manly spent 3 months in America and Eu- 

 rope trying to obtain at least the promise of an engine to meet their 

 requirements, but without success. It was decided therefore that 

 Manly should take up the further development of the Balzer engine. 

 Balzer had been working on both the quarter-scale and the full-scale 

 engines. All Balzer's engines were of the rotating-radial type, but 

 Manly decided, quite wisely, to use the stationary radial principle. 

 Using a number of parts made by Balzer, the full-scale engine which 

 he finally completed late in 1901 is shown in plate 5 with statistics in 

 table 1, page 294. 



This engine, described in detail in the Langley Memoirs, is now 

 displayed in the Smithsonian removed from the "aerodrome." Power 

 was carefully measured on a dynamometer and, most remarkably, sus- 

 tained for three consecutive 10-hour tests. The specific weight, 2.58 

 pounds per hp.,^ remained as a low record until the Liberty engine of 



' Without water or flywheels, but with Ignition battery. This condition Is the same as 

 for the weights quoted for other liquid-cooled engines. 



