RPT ADVISED THAT RNAV (GPS) Z RWY 10 MISSED APCH PROC AT STT CAN NOT BE FLOWN AS DESCRIBED ON THE PUBLISHED NACO AND COMMERCIAL VENDOR APCH CHARTS.

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I HAVE BEEN REVIEWING THE STT RNAV (GPS) Z RWY 10 SIAP IN CONJUNCTION WITH A PROPOSED AERONAUTICAL STUDY. DURING MY REVIEW I NOTICED THAT THE MISSED APCH INSTRUCTIONS APPEAR TO BE IN ERROR AND IMPOSSIBLE TO EXECUTE AS DIRECTED. HERE ARE MY THOUGHTS. THE MISSED APCH POINT IS THE LOGVY WP AND IS EXECUTED AT THAT POINT. THE INSTRUCTIONS DIRECT YOU TO CLB TO 2800 FT VIA LOGVY; THE R TURN VIA 166 DEG COURSE TO OSSEL AND HOLD. ALSO THE NEW 'GRAPHIC' MISSED APCH INSTRUCTIONS NOW INCLUDED WITH THE PROFILE VIEW SHOW A STRAIGHT CLB TO LOGVY THEN A R TURN TO 166 DEG TO OSSEL. I WONDER HOW YOU CAN CLB STRAIGHT TO A POINT YOU HAVE JUST PASSED AND FROM WHICH YOU ARE EXECUTING YOUR MISSED APCH. THE SYMBOL 'UP POINTING ARROW WITH AN ALT' INDICATES TO CLB STRAIGHT AHEAD TO AN ALT. IN THIS CASE I; AS THE PLT WOULD LOOK AT THIS AS 'STRAIGHT AHEAD UNTIL 2800 FT; THEN TO LOGVY'; BUT; 'OOPS LOGVY IS BEHIND ME'; THEN R TURN CRS 166 DEGS TO OSSEL. THIS ALMOST MAKE THE ASSUMPTION THAT THE PLT IS GOING TO GO MISSED APCH PRIOR TO LOGVY. IN ALL MY TRAINING; I DID NOT TRAIN TO GO MISSED APCH UNTIL THE MISSED APCH POINT (WHICH NEARLY ALL THE OTHER MISSED APCH INSTRUCTIONS INDICATE) WITH INSTRUCTIONS FROM THIS POINT. I WOULD THINK THAT THE MORE CORRECT INSTRUCTION (IN THIS CASE) IS A CLBING R TURN AT THE MISSED APCH POINT TO 2800 FT VIA CRS 166 DEGS TO OSSEL.