NAVIGATION PLAN "A" 



Sequence of Operations (See figure G-1) 



1. MIZAR arrives on station using Loran A and/or other surface navigation aids. 



2. MIZAR conducts local area bathymetry survey to establish best estimate of ALVIN 

 location. Bottom marker No. 1 is dropped as near ALVIN as possible (accuracy goal is 300- 

 400 yards). 



3. MIZAR stays on station using her three-dimensional computer system. 



4. MIZAR tracks ALUMINAUT on the surface with radar. 



5. MIZAR talks ALUMINAUT into position over marker No. 1. 



6. ALUMINAUT dives to bottom. MIZAR tracks ALUMINAUT during descent. 



7. ALUMINAUT is given courses to steer to home in on marker No. 1. 



8. ALUMINAUT conducts CTFM sonar search for ALVIN. During this search she uses 

 the CTFM transponder as a local navigation bottom reference. The surface also tracks ALU- 

 MINAUT. Depth contours will be a valuable guide. 



9. ALUMINAUT finds ALVIN and her position relative to marker No. 1 is recorded. 



Failure Mode Reactions for Navigation Plan "A" 



L If AMF transponder on marker No. 1 nearest ALVIN fails, call it back and set an- 

 other. 



2. If the CTFM transponder on marker No. 1 fails, continue with ALUMINAUT search 

 using surface tracking navigation. Set another if required. 



3. If the CTFM sonar on ALUMINAUT fails and if ALUMINAUT is on the bottom, 

 continue with a visual search using surface tracking navigation. Repair ALUMINAUT's 

 CTFM sonar. Install WHOI backup SM500 CTFM sonar. 



4. If MIZAR's computer tracking fails, shift to Navigation Plan "B". 



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