Narrative:

Were cleared for a runway 25L profile descent, then about tnp were cleared to intercept runway 24R approach. It puts the pilot free at that time to no longer go by the runway 25L profile descent, which has a 14000' and 18000' at civet. We crossed abeam civet at around 12500' and the center got very upset. The clearance to intercept runway 24R approach does not include runway 25L profile descent. There was no conflict of any traffic, alarms or anything, but a low altitude at abeam civet going to runway 24R, which is not the runway 25L profile. Callback conversation with reporter revealed the following: PIC called center after landing and they stated they had about 6 similar busts at civet that day. Later when they returned on another trip the center was issuing the clearance in a different way. Reporter stated that they should also have a profile for the runway 24 complex which would help do away with confusion. Claims runway 24 localizer too unstable that far out to use for navigation. Also stated that when clearance thought they should have requested clarification, but frequency was so busy did not want to bust in.

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Original NASA ASRS Text

Title: CLRNC INTERP RESULTS IN ACR WDB MISSING ALT RESTRICTION ON LAX PROFILE APCH.

Narrative: WERE CLRED FOR A RWY 25L PROFILE DSCNT, THEN ABOUT TNP WERE CLRED TO INTERCEPT RWY 24R APCH. IT PUTS THE PLT FREE AT THAT TIME TO NO LONGER GO BY THE RWY 25L PROFILE DSCNT, WHICH HAS A 14000' AND 18000' AT CIVET. WE CROSSED ABEAM CIVET AT AROUND 12500' AND THE CENTER GOT VERY UPSET. THE CLRNC TO INTERCEPT RWY 24R APCH DOES NOT INCLUDE RWY 25L PROFILE DSCNT. THERE WAS NO CONFLICT OF ANY TFC, ALARMS OR ANYTHING, BUT A LOW ALT AT ABEAM CIVET GOING TO RWY 24R, WHICH IS NOT THE RWY 25L PROFILE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: PIC CALLED CENTER AFTER LNDG AND THEY STATED THEY HAD ABOUT 6 SIMILAR BUSTS AT CIVET THAT DAY. LATER WHEN THEY RETURNED ON ANOTHER TRIP THE CENTER WAS ISSUING THE CLRNC IN A DIFFERENT WAY. RPTR STATED THAT THEY SHOULD ALSO HAVE A PROFILE FOR THE RWY 24 COMPLEX WHICH WOULD HELP DO AWAY WITH CONFUSION. CLAIMS RWY 24 LOC TOO UNSTABLE THAT FAR OUT TO USE FOR NAV. ALSO STATED THAT WHEN CLRNC THOUGHT THEY SHOULD HAVE REQUESTED CLARIFICATION, BUT FREQ WAS SO BUSY DID NOT WANT TO BUST IN.

Data retrieved from NASA's ASRS site as of August 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.