Narrative:

Our flight was being vectored around WX east of boulder city VOR. After clearing the WX we requested a radar vector to civet intersection--a heading of 215 degrees was given and later a heading of 225 degrees was assigned. At 132 DME lax a descent to FL240 at pilot's discretion was assigned, followed by 'begin your descent.' then the altitude FL220 was assigned. The next clearance was where the confusion began. On a heading of 215 or 225 degrees, we were cleared to intercept lax 25L localizer and fly it inbound, maintain 14000' until on the localizer. The lax runway 25L localizer was intercepted 65 DME lax at 14000'. We were asked to increase airspeed from 280 KTS to 300 KTS and increase airspeed again to 320 KTS. I do not recall being assigned a final altitude or being cleared for the profile descent. At the high airspeed (320 KTS) and the arnes intersection restrictions of 10000' and 250 KTS were given. The flight crew understood the clearance to mean 'cleared down to 10000' when on the lax runway 25L localizer.' if an altitude restriction of 14000' until civet intersection or cleared for the profile descent maintain 14000' until civet was given, this incident would not have happened. After passing approximately 12500' our altitude was questioned and we were instructed to return to 14000', cross civet at 14000', arnes 10000'/250 KTS, fueler 8000'/250 KTS, and maintain 210 KTS to downe. I am not placing blame on anyone, but my crew and I felt the clearance meant to continue the descent to 10000' once on the 25L localizer. It has been my policy, when in doubt ask. In this situation we felt center wanted us to continue our descent once on the lax 25L localizer. Supplemental information from acn 92908: there was no mention of crossing civet at 14000'. At 14000' both pilots asked each other about the altitude and both thought we were to intercept the localizer at 14000' or above and then continue down. If there had been a question about the altitude we would have questioned the controller. With the increased airspeed and the understanding of continuing the descent on the localizer and no mention of a civet altitude we felt the controller was keeping our speed up for sep (as stated earlier) and expecting us to be in a position to land at lax. In order to do this it looked like he had set us up for this by not mentioning a civet crossing restriction so we could be at arnes at 10000'/250 KTS. A position we would have to be in to make a successful approach at lax.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR HVT OVERSHOT CROSSING ALT ON PROFILE DESCENT.

Narrative: OUR FLT WAS BEING VECTORED AROUND WX E OF BOULDER CITY VOR. AFTER CLRING THE WX WE REQUESTED A RADAR VECTOR TO CIVET INTXN--A HDG OF 215 DEGS WAS GIVEN AND LATER A HDG OF 225 DEGS WAS ASSIGNED. AT 132 DME LAX A DSCNT TO FL240 AT PLT'S DISCRETION WAS ASSIGNED, FOLLOWED BY 'BEGIN YOUR DSCNT.' THEN THE ALT FL220 WAS ASSIGNED. THE NEXT CLRNC WAS WHERE THE CONFUSION BEGAN. ON A HDG OF 215 OR 225 DEGS, WE WERE CLRED TO INTERCEPT LAX 25L LOC AND FLY IT INBND, MAINTAIN 14000' UNTIL ON THE LOC. THE LAX RWY 25L LOC WAS INTERCEPTED 65 DME LAX AT 14000'. WE WERE ASKED TO INCREASE AIRSPD FROM 280 KTS TO 300 KTS AND INCREASE AIRSPD AGAIN TO 320 KTS. I DO NOT RECALL BEING ASSIGNED A FINAL ALT OR BEING CLRED FOR THE PROFILE DSCNT. AT THE HIGH AIRSPD (320 KTS) AND THE ARNES INTXN RESTRICTIONS OF 10000' AND 250 KTS WERE GIVEN. THE FLT CREW UNDERSTOOD THE CLRNC TO MEAN 'CLRED DOWN TO 10000' WHEN ON THE LAX RWY 25L LOC.' IF AN ALT RESTRICTION OF 14000' UNTIL CIVET INTXN OR CLRED FOR THE PROFILE DSCNT MAINTAIN 14000' UNTIL CIVET WAS GIVEN, THIS INCIDENT WOULD NOT HAVE HAPPENED. AFTER PASSING APPROX 12500' OUR ALT WAS QUESTIONED AND WE WERE INSTRUCTED TO RETURN TO 14000', CROSS CIVET AT 14000', ARNES 10000'/250 KTS, FUELER 8000'/250 KTS, AND MAINTAIN 210 KTS TO DOWNE. I AM NOT PLACING BLAME ON ANYONE, BUT MY CREW AND I FELT THE CLRNC MEANT TO CONTINUE THE DSCNT TO 10000' ONCE ON THE 25L LOC. IT HAS BEEN MY POLICY, WHEN IN DOUBT ASK. IN THIS SITUATION WE FELT CENTER WANTED US TO CONTINUE OUR DSCNT ONCE ON THE LAX 25L LOC. SUPPLEMENTAL INFO FROM ACN 92908: THERE WAS NO MENTION OF XING CIVET AT 14000'. AT 14000' BOTH PLTS ASKED EACH OTHER ABOUT THE ALT AND BOTH THOUGHT WE WERE TO INTERCEPT THE LOC AT 14000' OR ABOVE AND THEN CONTINUE DOWN. IF THERE HAD BEEN A QUESTION ABOUT THE ALT WE WOULD HAVE QUESTIONED THE CTLR. WITH THE INCREASED AIRSPD AND THE UNDERSTANDING OF CONTINUING THE DSCNT ON THE LOC AND NO MENTION OF A CIVET ALT WE FELT THE CTLR WAS KEEPING OUR SPD UP FOR SEP (AS STATED EARLIER) AND EXPECTING US TO BE IN A POS TO LAND AT LAX. IN ORDER TO DO THIS IT LOOKED LIKE HE HAD SET US UP FOR THIS BY NOT MENTIONING A CIVET XING RESTRICTION SO WE COULD BE AT ARNES AT 10000'/250 KTS. A POS WE WOULD HAVE TO BE IN TO MAKE A SUCCESSFUL APCH AT LAX.

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.