Narrative:

We were cleared to 7000 ft. At 6800 ft, ATC told us to watch for a wbound traffic at 8000 ft. We both looked up and saw the traffic. When I looked back in the cockpit, we were at 7350 ft. I started down to 7000 ft. Within seconds ATC said, 'nxxxx, please maintain 7000!' I said ok. Lesson -- 1 pilot look inside, 1 outside.

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Original NASA ASRS Text

Title: FLC OVERSHOOTS ALT ASSIGNED BY 350 FT.

Narrative: WE WERE CLRED TO 7000 FT. AT 6800 FT, ATC TOLD US TO WATCH FOR A WBOUND TFC AT 8000 FT. WE BOTH LOOKED UP AND SAW THE TFC. WHEN I LOOKED BACK IN THE COCKPIT, WE WERE AT 7350 FT. I STARTED DOWN TO 7000 FT. WITHIN SECONDS ATC SAID, 'NXXXX, PLEASE MAINTAIN 7000!' I SAID OK. LESSON -- 1 PLT LOOK INSIDE, 1 OUTSIDE.

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.