Narrative:

On departure from sjc airport after making the turn between 1.8 - 4.0 DME, we leveled off at 5000 ft until south of the 047 degree radial. After crossing the 050 degree radial or so the captain put 12000 ft in the mode control window and said to climb to 12000 ft. I began the climb knowing this was the next step in a busy departure. He rechked the pre departure clearance which said to maintain 5000 ft and instructed me to get back to 5000 ft. We were to wait for radar vectors to climb to 12000 ft and cross over san jose VOR at 12000 ft. I estimate our altitude about 5750 ft before descending back to 5000 ft. PNF comments in supplemental information from acn 452146: I had not previously read the pre departure clearance, probably because just as we were handed the final paperwork, including the pre departure clearance, a passenger discovered that she had left her cell phone in the terminal and asked us to check on it. Since it was the copilot's leg and he had impressed me as very competent, I let him take care of the paperwork, and I tried to run down the cell phone and still get out on schedule. I failed to review the pre departure clearance. Going on experience from previous sjc departures and the loupe 9 procedure description, and because I hadn't actually read the pre departure clearance, I believed we should climb after crossing the 047 degree radial to make our 12000 ft VOR crossing. I am not aware of any loss of separation and the controller did not comment on our altitude deviation.

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Original NASA ASRS Text

Title: ACR LEAVES ASSIGNED ALT WHEN FLYING SID WITHOUT CLRNC.

Narrative: ON DEP FROM SJC ARPT AFTER MAKING THE TURN BTWN 1.8 - 4.0 DME, WE LEVELED OFF AT 5000 FT UNTIL S OF THE 047 DEG RADIAL. AFTER XING THE 050 DEG RADIAL OR SO THE CAPT PUT 12000 FT IN THE MODE CTL WINDOW AND SAID TO CLB TO 12000 FT. I BEGAN THE CLB KNOWING THIS WAS THE NEXT STEP IN A BUSY DEP. HE RECHKED THE PDC WHICH SAID TO MAINTAIN 5000 FT AND INSTRUCTED ME TO GET BACK TO 5000 FT. WE WERE TO WAIT FOR RADAR VECTORS TO CLB TO 12000 FT AND CROSS OVER SAN JOSE VOR AT 12000 FT. I ESTIMATE OUR ALT ABOUT 5750 FT BEFORE DSNDING BACK TO 5000 FT. PNF COMMENTS IN SUPPLEMENTAL INFO FROM ACN 452146: I HAD NOT PREVIOUSLY READ THE PDC, PROBABLY BECAUSE JUST AS WE WERE HANDED THE FINAL PAPERWORK, INCLUDING THE PDC, A PAX DISCOVERED THAT SHE HAD LEFT HER CELL PHONE IN THE TERMINAL AND ASKED US TO CHK ON IT. SINCE IT WAS THE COPLT'S LEG AND HE HAD IMPRESSED ME AS VERY COMPETENT, I LET HIM TAKE CARE OF THE PAPERWORK, AND I TRIED TO RUN DOWN THE CELL PHONE AND STILL GET OUT ON SCHEDULE. I FAILED TO REVIEW THE PDC. GOING ON EXPERIENCE FROM PREVIOUS SJC DEPS AND THE LOUPE 9 PROC DESCRIPTION, AND BECAUSE I HADN'T ACTUALLY READ THE PDC, I BELIEVED WE SHOULD CLB AFTER XING THE 047 DEG RADIAL TO MAKE OUR 12000 FT VOR XING. I AM NOT AWARE OF ANY LOSS OF SEPARATION AND THE CTLR DID NOT COMMENT ON OUR ALTDEV.

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.