Narrative:

Descent into lima peru. ATC facility: lima center. Location: 115 mi north of sls VOR. On arrival into lima peru on the SLS1 arrival tokan transition there is a fix named WPT16. FMC shows to cross this fix at FL250 or above. The only fix on the arrival page of the commercial chart says to cross 110 mi from lima VOR at FL250 or above. This fix is approximately 56 mi too far north for the crossing on the approach plate. This fix is approximately 115 mi north of sls VOR, not lim VOR as it should be. This could let a crew think it is safe to descend 56 mi too early. Callback conversation with reporter revealed the following information: this reporter noticed the crossing restriction was drawn from sls instead of lim. In the program the flight crew uses, it gave a WPT16, which can be symbolic for 116 mi north of sls. However, the distance should be from lim, not sls. With the distance drawn from sls, this places aircraft at a lower altitude in mountainous terrain. Reporter feels that FMC was misprogrammed by the ground crew or dispatch. This programming update occurs on an every 5 to 6 week basis. Reporter has made contact with his dispatch office and they stated they were working on the problem. Dispatch has the responsibility for this type of problem.

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Original NASA ASRS Text

Title: A B757 DSNDING INTO LIMA, PERU, HAS AN INTERSECTION CROSSING RESTRICTION DRAWN TOO FAR AWAY FROM DESTINATION. THIS PLACES ACFT AT LOWER ALT IN MOUNTAINOUS TERRAIN.

Narrative: DSCNT INTO LIMA PERU. ATC FACILITY: LIMA CENTER. LOCATION: 115 MI N OF SLS VOR. ON ARRIVAL INTO LIMA PERU ON THE SLS1 ARRIVAL TOKAN TRANSITION THERE IS A FIX NAMED WPT16. FMC SHOWS TO CROSS THIS FIX AT FL250 OR ABOVE. THE ONLY FIX ON THE ARRIVAL PAGE OF THE COMMERCIAL CHART SAYS TO CROSS 110 MI FROM LIMA VOR AT FL250 OR ABOVE. THIS FIX IS APPROX 56 MI TOO FAR N FOR THE CROSSING ON THE APCH PLATE. THIS FIX IS APPROX 115 MI N OF SLS VOR, NOT LIM VOR AS IT SHOULD BE. THIS COULD LET A CREW THINK IT IS SAFE TO DSND 56 MI TOO EARLY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS RPTR NOTICED THE CROSSING RESTRICTION WAS DRAWN FROM SLS INSTEAD OF LIM. IN THE PROGRAM THE FLT CREW USES, IT GAVE A WPT16, WHICH CAN BE SYMBOLIC FOR 116 MI N OF SLS. HOWEVER, THE DISTANCE SHOULD BE FROM LIM, NOT SLS. WITH THE DISTANCE DRAWN FROM SLS, THIS PLACES ACFT AT A LOWER ALT IN MOUNTAINOUS TERRAIN. RPTR FEELS THAT FMC WAS MISPROGRAMMED BY THE GND CREW OR DISPATCH. THIS PROGRAMMING UPDATE OCCURS ON AN EVERY 5 TO 6 WEEK BASIS. RPTR HAS MADE CONTACT WITH HIS DISPATCH OFFICE AND THEY STATED THEY WERE WORKING ON THE PROBLEM. DISPATCH HAS THE RESPONSIBILITY FOR THIS TYPE OF PROBLEM.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.