Propulsive Effects of a Rotating Mass 



We must add that the immersion tests 

 are rather difficult and that we have dedi- 

 cated very little time to them. To the study 

 of navigation in immersion we must return 

 at another time. 



Tests in Air ' i it.vC • ' ' 



The tests were carried out by placing a 

 small two- mass device on two hydrogen- 

 filled balloons enclosed within a frame of 

 very light wood. The tests were performed 

 in a closed room with the air absolutely still. 



A device (Fig. 4) placed at one end of 

 the two balloons with the y axis horizontal, 

 made the balloons turn around vertical axes. 

 With the device rotating 180° around the y 

 axis, the balloons rotated in the opposite di- 

 rection. The device has the capacity to im- 

 part a forward motion to the balloons, but at 

 a very low speed. 



nn. a. i 4- 



'W).S.«4 



Fig. 20 - Diagram of 

 the turn of a model 

 destroyer 



These tests were also very difficult. We had to avoid the formation of air 

 currents, eliminate the vibrations of the two balloons, reduce to a minimum the 

 propulsive effect of the apparatus which stirs up the air, and limit the weight of 

 the apparatus as much as possible. 



Fig. Zl - Long device having 

 R = T = 0.80 meters for navi- 

 gation testing on the open sea 



1387 



