Narrative:

The BE40 checked on my frequency. At first I didn't know who he was or his position. I then located him south of dye at 6000 ft MSL. His data block indicated level at 6000 ft with a temporary altitude of 10000 ft and radar with sector 41. I was working at sector 40 by myself and conducting training for D40. (The sector was fully staffed 5 mins prior; but the r-side was switched to another sector due to traffic load.) the BE40's destination was O48. Sector 40 airspace is surface to 8000 ft MSL. Sector 41's airspace is 9000 ft to FL230; with the same lateral boundaries. O48 is at the north end of both sectors. The operational error occurred at the south end. Initially I thought sector 41 had the handoff and had pushed the aircraft up to me so he could climb through my airspace. Later found out trainee had taken handoff on BE40 put in temporary altitude of 10000 ft and handed off to sector 41. All this quickly without my notice. When the BE40 checked on I told him to maintain 6000 ft. I 'slant okayed' the data block to my sector and told sector 41 I would keep the aircraft and pointed him out for climb/descent. I was scanning the sector; when I was asked a question by sector 41; when the BE40 pilot asked a question at the same time. Without realizing I instructed him to 10000 ft instead of 6000 ft; which he needed to because of the E120 at 7000 ft. I had mistakenly read the temporary altitude inserted by the trainee.

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Original NASA ASRS Text

Title: ZOA CTLR EXPERIENCED OPERROR AT 7000 FT WHEN CLBING ACFT THROUGH OCCUPIED ALT.

Narrative: THE BE40 CHKED ON MY FREQ. AT FIRST I DIDN'T KNOW WHO HE WAS OR HIS POS. I THEN LOCATED HIM S OF DYE AT 6000 FT MSL. HIS DATA BLOCK INDICATED LEVEL AT 6000 FT WITH A TEMPORARY ALT OF 10000 FT AND RADAR WITH SECTOR 41. I WAS WORKING AT SECTOR 40 BY MYSELF AND CONDUCTING TRAINING FOR D40. (THE SECTOR WAS FULLY STAFFED 5 MINS PRIOR; BUT THE R-SIDE WAS SWITCHED TO ANOTHER SECTOR DUE TO TFC LOAD.) THE BE40'S DEST WAS O48. SECTOR 40 AIRSPACE IS SURFACE TO 8000 FT MSL. SECTOR 41'S AIRSPACE IS 9000 FT TO FL230; WITH THE SAME LATERAL BOUNDARIES. O48 IS AT THE N END OF BOTH SECTORS. THE OPERROR OCCURRED AT THE S END. INITIALLY I THOUGHT SECTOR 41 HAD THE HDOF AND HAD PUSHED THE ACFT UP TO ME SO HE COULD CLB THROUGH MY AIRSPACE. LATER FOUND OUT TRAINEE HAD TAKEN HDOF ON BE40 PUT IN TEMPORARY ALT OF 10000 FT AND HANDED OFF TO SECTOR 41. ALL THIS QUICKLY WITHOUT MY NOTICE. WHEN THE BE40 CHKED ON I TOLD HIM TO MAINTAIN 6000 FT. I 'SLANT OKAYED' THE DATA BLOCK TO MY SECTOR AND TOLD SECTOR 41 I WOULD KEEP THE ACFT AND POINTED HIM OUT FOR CLB/DSCNT. I WAS SCANNING THE SECTOR; WHEN I WAS ASKED A QUESTION BY SECTOR 41; WHEN THE BE40 PLT ASKED A QUESTION AT THE SAME TIME. WITHOUT REALIZING I INSTRUCTED HIM TO 10000 FT INSTEAD OF 6000 FT; WHICH HE NEEDED TO BECAUSE OF THE E120 AT 7000 FT. I HAD MISTAKENLY READ THE TEMPORARY ALT INSERTED BY THE TRAINEE.

Data retrieved from NASA's ASRS site as of January 2009 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.