Narrative:

Upon climb out, one of my passenger came up to the cockpit stating he heard an unfamiliar noise in the back cabin area. I allowed myself to get distraction by his concern. I was instructed to climb to 9000 ft by rhein control (german controller). My copilot, also distraction, missed the '1000 ft to go' call. The altimeter caught my eye around 9300 ft. I immediately retarded all 4 throttles and pushed the nose of the aircraft down. The passenger immediately returned to his seat with no further comments. I leveled the aircraft back to the assigned altitude and shortly thereafter received instructions to climb. The controller did not acknowledge any altitude deviation. There was no other traffic in the area on our TCASII. The next time a situation like this happens again on a 2-PLT crew, I will fly (or captain) the aircraft while the other pilot tries to understand the problem. Non critical problems such as this one will be handled during low workload (cockpit) and high altitude environment. The noise that ended up bothering the passenger was the stopper to the bathroom sink was not seated and was allowing a small amount of cabin air to exit the aircraft. Bottom line: someone has to be minding the aircraft. Any interruptions below 10000 ft should be for emergencys only! Note: the no smoking, fasten seat belt sign was still on when the passenger approached the cockpit.

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Original NASA ASRS Text

Title: CAPT OF A LOCKHEED JETSTAR 1329 (L329) OVERSHOT ALT DURING DEP DUE TO DISTR OF A PAX GOING INTO THE CABIN AND THE FO MISSING 1000 FT TO GO CALL. THE CAPT RECOGNIZED HIS MISTAKE AND CORRECTED BACK IMMEDIATELY.

Narrative: UPON CLBOUT, ONE OF MY PAX CAME UP TO THE COCKPIT STATING HE HEARD AN UNFAMILIAR NOISE IN THE BACK CABIN AREA. I ALLOWED MYSELF TO GET DISTR BY HIS CONCERN. I WAS INSTRUCTED TO CLB TO 9000 FT BY RHEIN CTL (GERMAN CTLR). MY COPLT, ALSO DISTR, MISSED THE '1000 FT TO GO' CALL. THE ALTIMETER CAUGHT MY EYE AROUND 9300 FT. I IMMEDIATELY RETARDED ALL 4 THROTTLES AND PUSHED THE NOSE OF THE ACFT DOWN. THE PAX IMMEDIATELY RETURNED TO HIS SEAT WITH NO FURTHER COMMENTS. I LEVELED THE ACFT BACK TO THE ASSIGNED ALT AND SHORTLY THEREAFTER RECEIVED INSTRUCTIONS TO CLB. THE CTLR DID NOT ACKNOWLEDGE ANY ALTDEV. THERE WAS NO OTHER TFC IN THE AREA ON OUR TCASII. THE NEXT TIME A SIT LIKE THIS HAPPENS AGAIN ON A 2-PLT CREW, I WILL FLY (OR CAPT) THE ACFT WHILE THE OTHER PLT TRIES TO UNDERSTAND THE PROB. NON CRITICAL PROBS SUCH AS THIS ONE WILL BE HANDLED DURING LOW WORKLOAD (COCKPIT) AND HIGH ALT ENVIRONMENT. THE NOISE THAT ENDED UP BOTHERING THE PAX WAS THE STOPPER TO THE BATHROOM SINK WAS NOT SEATED AND WAS ALLOWING A SMALL AMOUNT OF CABIN AIR TO EXIT THE ACFT. BOTTOM LINE: SOMEONE HAS TO BE MINDING THE ACFT. ANY INTERRUPTIONS BELOW 10000 FT SHOULD BE FOR EMERS ONLY! NOTE: THE NO SMOKING, FASTEN SEAT BELT SIGN WAS STILL ON WHEN THE PAX APCHED THE COCKPIT.

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.