Narrative:

Cleared for takeoff from hou, runway 22R, turn to heading 030 degrees. (Altitude cleared to with clearance was 4000 ft.) during takeoff brief by me, I verified 4000 ft level off. After takeoff we began our climb and right turn to 030 degrees. In our climb we were given traffic, an light transport at 2 O'clock climbing, has us in sight. I had the light transport on TCASII closing from 3 O'clock, 1000 plus below, first officer had a visual on the light transport. Tower cleared us to departure. At that time we were climbing through 5500 ft. Checking in with departure I reported climbing to 6000 ft through 5600 ft (6000 ft was set in the window). Departure control asked who cleared us to 6000 ft. We were caught, said nothing. Departure immediately cleared us to a higher altitude. After checking with the tower, no one had cleared us to 6000 ft. I believe we had the wrong altitude set in the altitude window, even though I looked at it, and reported 4000 ft during the takeoff brief. There was no conflict, as reported by departure. We continued without incident to our destination. Copilot was flying the aircraft. We may have caught the error had we not been concentrating on the light transport traffic.

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Original NASA ASRS Text

Title: FLC OF AN MLG ACR ACFT OVERSHOT ASSIGNED CLB ALT DUE TO MISSETTING THE ALT ALERTER.

Narrative: CLRED FOR TKOF FROM HOU, RWY 22R, TURN TO HDG 030 DEGS. (ALT CLRED TO WITH CLRNC WAS 4000 FT.) DURING TKOF BRIEF BY ME, I VERIFIED 4000 FT LEVEL OFF. AFTER TKOF WE BEGAN OUR CLB AND R TURN TO 030 DEGS. IN OUR CLB WE WERE GIVEN TFC, AN LTT AT 2 O'CLOCK CLBING, HAS US IN SIGHT. I HAD THE LTT ON TCASII CLOSING FROM 3 O'CLOCK, 1000 PLUS BELOW, FO HAD A VISUAL ON THE LTT. TWR CLRED US TO DEP. AT THAT TIME WE WERE CLBING THROUGH 5500 FT. CHKING IN WITH DEP I RPTED CLBING TO 6000 FT THROUGH 5600 FT (6000 FT WAS SET IN THE WINDOW). DEP CTL ASKED WHO CLRED US TO 6000 FT. WE WERE CAUGHT, SAID NOTHING. DEP IMMEDIATELY CLRED US TO A HIGHER ALT. AFTER CHKING WITH THE TWR, NO ONE HAD CLRED US TO 6000 FT. I BELIEVE WE HAD THE WRONG ALT SET IN THE ALT WINDOW, EVEN THOUGH I LOOKED AT IT, AND RPTED 4000 FT DURING THE TKOF BRIEF. THERE WAS NO CONFLICT, AS RPTED BY DEP. WE CONTINUED WITHOUT INCIDENT TO OUR DEST. COPLT WAS FLYING THE ACFT. WE MAY HAVE CAUGHT THE ERROR HAD WE NOT BEEN CONCENTRATING ON THE LTT TFC.

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.