Narrative:

We accidentally leveled off at 34720 ft instead of FL350. We took off with an altimeter setting of 30.22. Both crew members missed resetting the altimeter to 29.92 passing through FL180. Distractions in the cockpit more than likely distracted us. Crew members from the back asking questions, etc. We discovered the problem when ATC informed us they had showed us level below assigned altitude for 30 seconds. We then discovered the altimeter setting was not 29.92, reset it, and climbed 280 ft to level at FL350. Supplemental information from acn 468751: leveled off at 34,720 ft due to not setting 29.92 passing the transition altitude. Altimeter setting of 30.22 gave us our filed altitude of FL350 until center said we were 'a couple hundred ft low' for about 30 seconds. A more sterile cockpit for the entire climb profile and a procedure of waiting until the transition altitude would have prevented this.

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Original NASA ASRS Text

Title: MIL DC9 CREW DID NOT SET QNE AT THE TRANSITION LEVEL.

Narrative: WE ACCIDENTALLY LEVELED OFF AT 34720 FT INSTEAD OF FL350. WE TOOK OFF WITH AN ALTIMETER SETTING OF 30.22. BOTH CREW MEMBERS MISSED RESETTING THE ALTIMETER TO 29.92 PASSING THROUGH FL180. DISTRACTIONS IN THE COCKPIT MORE THAN LIKELY DISTRACTED US. CREW MEMBERS FROM THE BACK ASKING QUESTIONS, ETC. WE DISCOVERED THE PROB WHEN ATC INFORMED US THEY HAD SHOWED US LEVEL BELOW ASSIGNED ALT FOR 30 SECONDS. WE THEN DISCOVERED THE ALTIMETER SETTING WAS NOT 29.92, RESET IT, AND CLBED 280 FT TO LEVEL AT FL350. SUPPLEMENTAL INFO FROM ACN 468751: LEVELED OFF AT 34,720 FT DUE TO NOT SETTING 29.92 PASSING THE TRANSITION ALT. ALTIMETER SETTING OF 30.22 GAVE US OUR FILED ALT OF FL350 UNTIL CTR SAID WE WERE 'A COUPLE HUNDRED FT LOW' FOR ABOUT 30 SECONDS. A MORE STERILE COCKPIT FOR THE ENTIRE CLB PROFILE AND A PROC OF WAITING UNTIL THE TRANSITION ALT WOULD HAVE PREVENTED THIS.

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.