Narrative:

We were cleared for the san mateo 2 arrival to land O5R at mex. Maintaining 12000 ft/240 KTS approaching smo VOR from the nne at approximately 6 mi inbound to VOR we were cleared to 9500 ft (conditions were VFR with good visibility, ground and mountains were in sight). At approximately 3 mi from smo approach control asked what altitude we were descending to. We stated 9500 ft assigned at which time they told us to level at 11000 ft. However, we were already at 10500 ft and starting our outbound turn to 160 degree over smo we stated this fact and were further cleared for the approach descending to 9500 ft as per arrival plate 10-2D mex. We were visual with the ground at all times and did not start our descent out of 12000 ft until past the high ground to the northeast of smo ie, 9840 ft and 10203 ft terrain clearance was maintained at all times.

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Original NASA ASRS Text

Title: ACR LGT ALT DEV EXCURSION FROM CLRNC ALT.

Narrative: WE WERE CLRED FOR THE SAN MATEO 2 ARR TO LAND O5R AT MEX. MAINTAINING 12000 FT/240 KTS APCHING SMO VOR FROM THE NNE AT APPROX 6 MI INBOUND TO VOR WE WERE CLRED TO 9500 FT (CONDITIONS WERE VFR WITH GOOD VISIBILITY, GND AND MOUNTAINS WERE IN SIGHT). AT APPROX 3 MI FROM SMO APCH CTL ASKED WHAT ALT WE WERE DSNDING TO. WE STATED 9500 FT ASSIGNED AT WHICH TIME THEY TOLD US TO LEVEL AT 11000 FT. HOWEVER, WE WERE ALREADY AT 10500 FT AND STARTING OUR OUTBOUND TURN TO 160 DEG OVER SMO WE STATED THIS FACT AND WERE FURTHER CLRED FOR THE APCH DSNDING TO 9500 FT AS PER ARR PLATE 10-2D MEX. WE WERE VISUAL WITH THE GND AT ALL TIMES AND DID NOT START OUR DSCNT OUT OF 12000 FT UNTIL PAST THE HIGH GND TO THE NE OF SMO IE, 9840 FT AND 10203 FT TERRAIN CLRNC WAS MAINTAINED AT ALL TIMES.

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.