Narrative:

We were climbing out of dtw to 20000 ft, in contact with zle. I was the PNF. The captain was flying. I was completing the climb checklist, which included briefing the passenger. I told the captain I was going off communication #1. The captain said she had control of communication #2 radio and control of the aircraft. At the time I left the radio we were climbing through 16500 ft. I did the briefing and returned to communication #1 as we were leveling off at 19000 ft. This was the new altitude that was received while I was off the radios. The altimeters were not reset to 29.92 inches as we passed 18000 ft. We leveled off 400 ft high. It is normal procedure to do the briefing during the climb. From now on I will brief only during level flight.

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Original NASA ASRS Text

Title: FAILURE TO SET ALTIMETER TO 29.92 INCHES AFTER FL180 RESULTED IN ALTDEV ALT OVERSHOT.

Narrative: WE WERE CLBING OUT OF DTW TO 20000 FT, IN CONTACT WITH ZLE. I WAS THE PNF. THE CAPT WAS FLYING. I WAS COMPLETING THE CLB CHKLIST, WHICH INCLUDED BRIEFING THE PAX. I TOLD THE CAPT I WAS GOING OFF COM #1. THE CAPT SAID SHE HAD CTL OF COM #2 RADIO AND CTL OF THE ACFT. AT THE TIME I LEFT THE RADIO WE WERE CLBING THROUGH 16500 FT. I DID THE BRIEFING AND RETURNED TO COM #1 AS WE WERE LEVELING OFF AT 19000 FT. THIS WAS THE NEW ALT THAT WAS RECEIVED WHILE I WAS OFF THE RADIOS. THE ALTIMETERS WERE NOT RESET TO 29.92 INCHES AS WE PASSED 18000 FT. WE LEVELED OFF 400 FT HIGH. IT IS NORMAL PROC TO DO THE BRIEFING DURING THE CLB. FROM NOW ON I WILL BRIEF ONLY DURING LEVEL FLT.

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.