Unusual Two-Propeller Arrangements 



INTERLOCKING PROPELLERS 

 1 PROPELLER 

 INWARD 

 16 KNOTS 



INTERLOCKING PROPELLERS 

 2 PROPELLERS 

 INWARD 

 16 KNOTS 



.._.-i 



INTERLOCKING PROPELLERS 

 1 PROPELLER 

 OUTWARD 

 16 KNOTS 



'ss^mm. . 



INTERLOCKING PROPELLERS 

 2 PROPELLERS 

 OUTWARD 

 16 KNOTS 



Fig. 12 - Propeller blade stress recordings (Continued) 



1537 



