Narrative:

I was monitoring my trnee during a moderate traffic period. An air carrier departed runway 23 at mc ghee tyson airport. The aircraft was runway heading climbing to 6000'. My trnee instructed the aircraft to turn left heading 1-1-0 and to climb and maintain 1-0-thousand. Later, as my trnee was changing the aircraft to atl center frequency, we noticed the aircraft starting to climb out of 10000'. We instructed the aircraft to maintain 1-0-thousand. The aircraft ended up at 1-1-thousand. Higher altitude was obtained from atl center and the aircraft was changed (frequency) to them. The facility manager was next to us in the TRACON at the time. He and I reviewed the tape. We (my trnee) had issued the correct altitude, but the pilot had read back heading 1-1-0 and maintain 1-1-thousand. Neither the trnee nor myself caught the erroneous altitude readback. I was charged with a system deviation. Perhaps the pilot thought he heard an altitude of 1-1-thousand since the heading issued was 1-1-0. Maybe I would have been more likely to catch the erroneous readback on the altitude if I had been directly communicating and watching the aircraft rather than monitoring my trnee.

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Original NASA ASRS Text

Title: ACR CLIMBED ABOVE ALT INTENDED BY ATC. OPERATIONAL DEVIATION.

Narrative: I WAS MONITORING MY TRNEE DURING A MODERATE TFC PERIOD. AN AIR CARRIER DEPARTED RWY 23 AT MC GHEE TYSON ARPT. THE ACFT WAS RWY HDG CLBING TO 6000'. MY TRNEE INSTRUCTED THE ACFT TO TURN LEFT HDG 1-1-0 AND TO CLB AND MAINTAIN 1-0-THOUSAND. LATER, AS MY TRNEE WAS CHANGING THE ACFT TO ATL CENTER FREQ, WE NOTICED THE ACFT STARTING TO CLB OUT OF 10000'. WE INSTRUCTED THE ACFT TO MAINTAIN 1-0-THOUSAND. THE ACFT ENDED UP AT 1-1-THOUSAND. HIGHER ALT WAS OBTAINED FROM ATL CENTER AND THE ACFT WAS CHANGED (FREQ) TO THEM. THE FAC MGR WAS NEXT TO US IN THE TRACON AT THE TIME. HE AND I REVIEWED THE TAPE. WE (MY TRNEE) HAD ISSUED THE CORRECT ALT, BUT THE PLT HAD READ BACK HDG 1-1-0 AND MAINTAIN 1-1-THOUSAND. NEITHER THE TRNEE NOR MYSELF CAUGHT THE ERRONEOUS ALT READBACK. I WAS CHARGED WITH A SYS DEV. PERHAPS THE PLT THOUGHT HE HEARD AN ALT OF 1-1-THOUSAND SINCE THE HDG ISSUED WAS 1-1-0. MAYBE I WOULD HAVE BEEN MORE LIKELY TO CATCH THE ERRONEOUS READBACK ON THE ALT IF I HAD BEEN DIRECTLY COMMUNICATING AND WATCHING THE ACFT RATHER THAN MONITORING MY TRNEE.

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.