B767 ACFT FLYING INTO FOREIGN ARPT; SCL; RECEIVED CLRNC DIRECT TO A FIX AND THEN WHEN SWITCHING TO APCH CTL THEY GIVE CLRNC FOR AN ARR AND 5000 FT. RPTR STATES THAT IT IS A TRAP THAT FLCS WILL ASSUME THEY CAN COMMENCE DSCNT ON THE DIRECT ROUTING WHICH IS NOT WHAT THE CTLRS EXPECT AND THE FLC COULD BE DSNDING TOO SOON INTO HIGH TERRAIN.

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IN LATIN AMERICA THE ATC USE OF THE WORDS 'FLY DIRECT' OR 'CLRED TO A FIX' ARE VERY COMMON; BUT OFTEN THEY MEAN 'MAINTAIN YOUR FLT PLAN RTE.' PLTS OFTEN FLY DIRECT. WE REALLY NEED TO RE-ADDRESS THIS GOTCHA. HERE IS A PRIME EXAMPLE. YOU ARE FLYING INTO SCL AND SANTIAGO CTR SAYS CLRED DIRECT TABON. A FEW SECONDS LATER YOU SWITCH TO SANTIAGO APCH AND THEY SAY CLRED THE ANDES 2 ARR 5000 FT. NOW THERE ARE SOME DETAILED NOTES IN THE FLT PLAN ABOUT HOW TO PROPERLY LOAD THE ANDES 2; BUT THEY DO NOT APPLY TO YOUR RTE OF FLT; BUT TO ANOTHER RTE SOMETIMES USED. YOUR RTE OF FLT GOES FROM TONGOY TO SOME FIX NOT EVEN ON THE ANDES 2 ARR. SO WHEN YOU GET CLRED DIRECT TABON ANDES 2 ARR; IT SOUNDS JUST LIKE CLRED DIRECT JUNUR FOWEE 3 ARR. BUT I GUARANTEE YOU THAT SANTIAGO CTR AND APCH DO NOT WANT YOU TO FLY DIRECT TABON AND IGNORE THE ANDES 2 STEPDOWN FIXES AND DSND TO 5000 FT. MANY; MANY PLTS THINK THAT CLRED DIRECT MEANS FLY DIRECT. SO WHEN YOU ARE COMING IN OVER THE WATER AND THE SIT IS SOMEWHAT CONFUSING BECAUSE THE DETAILED NOTES DO NOT REALLY APPLY; YOUR FLT PLAN FLIES TO SOME MADE UP FIX THAT IS NOT EVEN ON THE ARR; AND SANTIAGO WITH RADAR COVERAGE GIVES A SIMPLE CLRNC LIKE FLY DIRECT TABON ANDES 2 ARR -- WELL YOU COULD EASILY END UP IN THE ROCKS OR OFF COURSE. IT IS A DEFINITE GOTCHA THAT NEEDS TO BE ADDRESSED BECAUSE SOME PLTS DO EXACTLY WHAT ATC SAYS AND START DOWN EARLY. YIKES.