Narrative:

During slowing, turning descent on dogleg to downwind runway 4R ord, we busted a 7000 ft altitude clearance and were called by ATC approaching 6600 ft with an aircraft passing underneath at 5000 ft MSL right to left. Captain climbed back to 7000 ft and approach was uneventful thereafter. Contributing factors: continually changing assigned leveloff altitude in the descent without ever reaching one before it was changed lower. First officer and so both attempting to identify the ILS set on the captain's VHF navigation. Loss of awareness of cleared altitude on my part due to the continual changes and other duties (opening pack doors).

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Original NASA ASRS Text

Title: B727 SO UNABLE TO ASSIST OTHER CREW MEMBERS TO KEEP UP WITH CHANGING COCKPIT DEMANDS DUTIES RESULTED IN THE ALT OVERSHOOT UNDER C90 CTL AND CONFLICTING WITH OTHER TFC IN THE IMMEDIATE AREA.

Narrative: DURING SLOWING, TURNING DSCNT ON DOGLEG TO DOWNWIND RWY 4R ORD, WE BUSTED A 7000 FT ALT CLRNC AND WERE CALLED BY ATC APCHING 6600 FT WITH AN ACFT PASSING UNDERNEATH AT 5000 FT MSL R TO L. CAPT CLBED BACK TO 7000 FT AND APCH WAS UNEVENTFUL THEREAFTER. CONTRIBUTING FACTORS: CONTINUALLY CHANGING ASSIGNED LEVELOFF ALT IN THE DSCNT WITHOUT EVER REACHING ONE BEFORE IT WAS CHANGED LOWER. FO AND SO BOTH ATTEMPTING TO IDENT THE ILS SET ON THE CAPT'S VHF NAV. LOSS OF AWARENESS OF CLRED ALT ON MY PART DUE TO THE CONTINUAL CHANGES AND OTHER DUTIES (OPENING PACK DOORS).

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.