358 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1961 



Each engine will be considered separately from the standpoints of 

 history, specifications, capabilities, and survival value. Two of them 

 were used in heavier-than-air craft, and one powered a lighter-than- 

 air craft. All three were ancestors of distinct types of heavier-than- 

 air craft powerplants. 



THE CLEMENT ENGINE 



The first of these engines to power an aircraft was the Brazilian 

 Santos Dumont's French built and designed Clement motor (made by 

 Adolphe Clement, who later founded the famous Clement-Bayard 

 firm) which propelled his airship No. 9 during the summer of 1903. 

 To quote from his book, "My Air-ships" : 



I determined to build a small airship runabout for my pleasure and conven- 

 ience only. ... So I built my number 9, the smallest of possible dirigibles, yet 

 very practical indeed. As originally constructed, its balloon capacity was but 

 7,770 cubic feet, permitting me to take up less than 66 pounds of ballast; and 

 thus I navigated it for weeks, without inconvenience. Even when I enlarged 

 its balloon to 9,218 cubic feet, the balloon of my number 6, in which I won 

 the Deutsch Prize, would have made almost three of it, while that of my 

 Omnibus is fully eight times its size. As I have already stated, its 3 horse- 

 power Clement motor weighs but 261/^ pounds. With such a motor one cannot 

 expect great speed ; nevertheless, this handy little runabout takes me over the 

 Bois [Paris] at between 12 and 15 miles per hour, and this notwithstanding its 

 egg-shaped form, which would seemingly be little calculated for cutting the air. 



Further information is given in an article which appeared in the 

 Scientific American for July 11, 1903 : 



The new Clement gasoline motor used on the number 9 has proved especially 

 satisfactory. The little motor with its cylinders joined in the form of a V to 

 a round aluminum crank box, seems like a toy and weighs but 26^^ pounds, 

 although it will develop 3 horse power. The weight per horse power (8.8 

 pounds), the smallest that has yet been reached, is the result of long experience 

 in racing cars, where the weight must be cut down to a minimum. Current 

 for the spark is supplied by a battery and induction coil of the motor-bicycle 

 pattern. The motor is connected through a light friction clutch to the long 

 shaft which passes back of the propeller. A bicycle wheel with a heavy rim 

 (without the tire) forms the flywheel and lies next to the motor. ... An aii'- 

 bag of 60 cubic yards lies along the inside of the balloon at the bottom, forming 

 a pocket which can be filled out with air by a fan [blower] mounted on the motor 

 shaft. The balloon is [therefore] always kept in shape as the gas escapes. 



SPECIFICATIONS 



Cylinders 2 arranged in the form of a V. 



Cooling Air. 



Carburetion Automobile-type carburetor. 



Ignition Battery, induction coil, spark plug (high-tension). 



Horsepower 3. 



Bore and stroke 2^4 x 2% in. 



Displacement 21.8 cu. in. 



Dimensions 17 in. high x 9^2 in. wide x 9 in. long. 



Weight 261/^ lb. 



Weight/hp. ratio 8.8 lb. per hp. 



Country of manufacture France. 



