Global Transportation 93 



The Rocket Motor 



Reports from Britain say that the Nazis use rocket power to 

 get JU-88's off the ground with a three thousand-pound over- 

 load. The rockets are carried under the fuselage belly and are 

 dropped when the plane attains the required take-off speed. 

 Besides the use of rocket power (jet propulsion) there are 

 indications that the Nazis also use tow lines as well as cata- 

 pults to hurl their heavy planes into the air. 



Experiments with small jet motors, conducted by Dr. R. H. 

 Goddard, the American Rocket Society, and others, appear 

 to prove that these motors warrant consideration as auxiliary 

 booster motors to function during take-off or at any other 

 time that a burst of great power is needed. 



The jet or rocket motor is internal combustion in its sim- 

 plest form. It usually consists only of a combustion chamber 

 and a nozzle. Liquid fuels, usually hydrocarbons and liquid 

 oxygen, are fed into the chamber under pressure. Upon igni- 

 tion, by spark plug or other means, the combustion is con- 

 tinuous and the exhaust leaves the nozzle at great velocity, 

 thereby creating an equal reaction in the opposite direction 

 like the recoil of a gun when it is fired. The force of this 

 reaction depends upon the velocity of jet. Jet velocities have 

 reached sixty-five hundred feet in a second (over four thou- 

 sand miles per hour), which would be the speed of the rocket 

 in an absolute vacuum. The rocket engine is the most ineffi- 

 cient of all motors at low speeds, but this should not hamper 

 its use now. Effectiveness is more important than efficiency in 

 wartime. 



A jet-propelled aircraft, designed by Signor Campini and 

 built by the Caproni Airplane Company of Milan, Italy, flew 

 one hundred and sixty-eight miles at an average speed of one 

 hundred and thirty miles per hour in December, 1941. Air is 

 taken in at the hollow nose of this propellerless plane and ac- 



