Narrative:

On descent into den, cleared direct den VOR to maintain 11000 ft -- expecting vectors to land runway 17R. Traffic departing runway 17L caused an RA forcing a level off at 11400 ft. Once clear of conflict, captain continued descent (non-autoflt) to 11000 ft. We were told to expect runway 7. I advised approach of the RA, and they responded ok, but questioned me about our current altitude. When I looked up, the captain was still in a descent, and we were indicating 10700 ft. Approach re-emphasized we were cleared to 11000 ft and switched us to the next controller. In retrospect, non-use of autoflt, coupled with a change in runway assignment, and an RA distraction us from the primary responsibility of 'fly the aircraft first,' resulting in a momentary altitude deviation. As a PNF, I should have been more aware of the level off prior to busying myself with setting up for runway 7.

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Original NASA ASRS Text

Title: B737 FLT CREW HAS ALTDEV DURING APCH TO DEN.

Narrative: ON DSCNT INTO DEN, CLRED DIRECT DEN VOR TO MAINTAIN 11000 FT -- EXPECTING VECTORS TO LAND RWY 17R. TFC DEPARTING RWY 17L CAUSED AN RA FORCING A LEVEL OFF AT 11400 FT. ONCE CLR OF CONFLICT, CAPT CONTINUED DSCNT (NON-AUTOFLT) TO 11000 FT. WE WERE TOLD TO EXPECT RWY 7. I ADVISED APCH OF THE RA, AND THEY RESPONDED OK, BUT QUESTIONED ME ABOUT OUR CURRENT ALT. WHEN I LOOKED UP, THE CAPT WAS STILL IN A DSCNT, AND WE WERE INDICATING 10700 FT. APCH RE-EMPHASIZED WE WERE CLRED TO 11000 FT AND SWITCHED US TO THE NEXT CTLR. IN RETROSPECT, NON-USE OF AUTOFLT, COUPLED WITH A CHANGE IN RWY ASSIGNMENT, AND AN RA DISTR US FROM THE PRIMARY RESPONSIBILITY OF 'FLY THE ACFT FIRST,' RESULTING IN A MOMENTARY ALTDEV. AS A PNF, I SHOULD HAVE BEEN MORE AWARE OF THE LEVEL OFF PRIOR TO BUSYING MYSELF WITH SETTING UP FOR RWY 7.

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.