Narrative:

I was working when cpr X departed charlotte and climbed to 8000 ft. Aircraft Y departed another field and was given a climb to 12000 ft. X said was that for us. I said negative aircraft 2 climb and maintain 12000 ft. I then told X to maintain 8000 ft. X read back 12000 ft and I missed it. X climbed through the altitude of air carrier Z at 9000 ft. X and Y were on separate frequencys. The sectors were busy and trying to get split out. Supervisor was talking to me. Clearance being issued off satellite fields. X wanted a climb so bad and thought he heard that. I wanted to correct it, issued 8000 ft, and wanted to hear that. Total responsibility of readback error falls with me. X questioned the altitude once with no response. Question it again. Supplemental information from acn 268323: climbing on assigned heading of 250 degrees to join departure transition. Cleared to 12000 ft by controller. 12000 ft was read back by first officer. Upon topping overcast at approximately 9200 ft, saw dc-9 at 2 - 2:30 O'clock position heading approximately 180 degrees and 200-500 estimated ft above our altitude. Dc-9 approach in level flight. Dc-9 passed approximately 1500-2500 ft to our rear. No evasive action necessary by either aircraft. Controller asked us to verify our assigned altitude to which first officer responded 12000 ft. No other comments from controller. Believe controller had excessive workload. Supplemental information from acn 268313: controller made transmission X turn to 250 degrees for intercept 270 degree radial clt VOR and to climb to 12000 ft. (Transmission was broken toward end.) we acknowledged and repeated instruction to turn to 250 degrees and climb to 12000 ft. Supplemental information from acn 268801: Z was clear of the clouds, above an overcast, on the shine arrival into clt. Approximately 10 NM northwest of clt we were level at our assigned altitude of 9000 ft when the approach controller gave us a left turn to 090 degrees and advised us of traffic at 12 O'clock, same altitude. We then spotted a citation at 2 O'clock passing off our right at what we estimated to be less than 1 mi. Why was the warning not issued earlier and secondly, when the warning was issued, there did not seem to be any sense of urgency. The word 'immediate' was not used. The controller used our call sign and advised us to turn left to 090 degrees at which time my first officer and I were both reaching down to reset our heading bugs to the appropriate heading. I took this as a routine vector and communication until the controller got to the part about 'same altitude.' we had barely initiated the turn when we spotted the traffic already at our 2 O'clock passing off to our right.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR X UNAUTH CLB NON ADHERENCE TO ATC CLRNC CLB THROUGH OCCUPIED ALT HAD LTSS FROM ACR Y. SYS ERROR. PLTDEV.

Narrative: I WAS WORKING WHEN CPR X DEPARTED CHARLOTTE AND CLBED TO 8000 FT. ACFT Y DEPARTED ANOTHER FIELD AND WAS GIVEN A CLB TO 12000 FT. X SAID WAS THAT FOR US. I SAID NEGATIVE ACFT 2 CLB AND MAINTAIN 12000 FT. I THEN TOLD X TO MAINTAIN 8000 FT. X READ BACK 12000 FT AND I MISSED IT. X CLBED THROUGH THE ALT OF ACR Z AT 9000 FT. X AND Y WERE ON SEPARATE FREQS. THE SECTORS WERE BUSY AND TRYING TO GET SPLIT OUT. SUPVR WAS TALKING TO ME. CLRNC BEING ISSUED OFF SATELLITE FIELDS. X WANTED A CLB SO BAD AND THOUGHT HE HEARD THAT. I WANTED TO CORRECT IT, ISSUED 8000 FT, AND WANTED TO HEAR THAT. TOTAL RESPONSIBILITY OF READBACK ERROR FALLS WITH ME. X QUESTIONED THE ALT ONCE WITH NO RESPONSE. QUESTION IT AGAIN. SUPPLEMENTAL INFO FROM ACN 268323: CLBING ON ASSIGNED HDG OF 250 DEGS TO JOIN DEP TRANSITION. CLRED TO 12000 FT BY CTLR. 12000 FT WAS READ BACK BY FO. UPON TOPPING OVCST AT APPROX 9200 FT, SAW DC-9 AT 2 - 2:30 O'CLOCK POS HDG APPROX 180 DEGS AND 200-500 ESTIMATED FT ABOVE OUR ALT. DC-9 APCH IN LEVEL FLT. DC-9 PASSED APPROX 1500-2500 FT TO OUR REAR. NO EVASIVE ACTION NECESSARY BY EITHER ACFT. CTLR ASKED US TO VERIFY OUR ASSIGNED ALT TO WHICH FO RESPONDED 12000 FT. NO OTHER COMMENTS FROM CTLR. BELIEVE CTLR HAD EXCESSIVE WORKLOAD. SUPPLEMENTAL INFO FROM ACN 268313: CTLR MADE XMISSION X TURN TO 250 DEGS FOR INTERCEPT 270 DEG RADIAL CLT VOR AND TO CLB TO 12000 FT. (XMISSION WAS BROKEN TOWARD END.) WE ACKNOWLEDGED AND REPEATED INSTRUCTION TO TURN TO 250 DEGS AND CLB TO 12000 FT. SUPPLEMENTAL INFO FROM ACN 268801: Z WAS CLR OF THE CLOUDS, ABOVE AN OVCST, ON THE SHINE ARR INTO CLT. APPROX 10 NM NW OF CLT WE WERE LEVEL AT OUR ASSIGNED ALT OF 9000 FT WHEN THE APCH CTLR GAVE US A L TURN TO 090 DEGS AND ADVISED US OF TFC AT 12 O'CLOCK, SAME ALT. WE THEN SPOTTED A CITATION AT 2 O'CLOCK PASSING OFF OUR R AT WHAT WE ESTIMATED TO BE LESS THAN 1 MI. WHY WAS THE WARNING NOT ISSUED EARLIER AND SECONDLY, WHEN THE WARNING WAS ISSUED, THERE DID NOT SEEM TO BE ANY SENSE OF URGENCY. THE WORD 'IMMEDIATE' WAS NOT USED. THE CTLR USED OUR CALL SIGN AND ADVISED US TO TURN L TO 090 DEGS AT WHICH TIME MY FO AND I WERE BOTH REACHING DOWN TO RESET OUR HDG BUGS TO THE APPROPRIATE HDG. I TOOK THIS AS A ROUTINE VECTOR AND COM UNTIL THE CTLR GOT TO THE PART ABOUT 'SAME ALT.' WE HAD BARELY INITIATED THE TURN WHEN WE SPOTTED THE TFC ALREADY AT OUR 2 O'CLOCK PASSING OFF TO OUR R.

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.