Sahreiber^ Bentkowsky and Kerr 



Fig. 32. Mating Geometry 



A TYPICAL SIMULATION RUN 



The mating situation to be described is depicted schemati- 

 cally in Fig. 32. The DISSUB is rolled 225 degrees in an athwart- 

 ship current, so that the DSRV is required to mate bow up. With 

 the DSRV heading into the free stream, the interaction forces and 

 moments are as depicted in Fig. 33. Deflection of current off the 

 sail of the DISSUB causes a starboard sway force on the DSRV. 

 The corresponding yaw moment is counterclockwise at large separa- 

 tions, but becomes clockwise as the DSRV approaches the DISSUB. 

 The normal force provides a suction effect at relatively large dis- 

 placements, but becomes destabilizing as the DSRV approaches the 

 DISSUB. Thus the normal force, due to interaction, adds to the 

 force due to the free stream and tends to push the DSRV away from 

 the hatch. Pitch moments remain rather constant over the distance 

 Included in the run. 



In performing the mating operation the pilot attempts to head 

 into the local stream rather than into the free streain. He sees and 

 "feels" the DSRV sway and adjusts his heading to minimize the sway 

 motions. Thus, the relative heading Is not Into the free stream but 



1174 



