Airbus Industrie Undifferentiated or Other Model
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface; Situational Awareness; Workload
Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Human Factors; Procedure
Descending on the BEREE 1 RNAV arrival into DFW; we were given an initial descent from FL350-FL240; asked to be below FL290 within 4 minutes. Shortly thereafter; told to descend via the arrival (lowest altitude 11;000 FT). Could not use managed descent due to the ATC request for the expedited descent; so I used vertical speed descent. Somewhere prior to MUZZY intersection; passing through about FL210; ATC asked if we were given a different arrival as we were already below the FL240 restriction at MUZZY. I then realized I had never switched back to managed descent from vertical speed once we were below FL290 which meant that the plane would not honor the constraint. The Pilot Not Flying admitted our mistake; and the controller told us to just maintain FL210; then continue to descend via the arrival after MUZZY. There was no loss of separation with any other aircraft that we were aware of. As Pilot Flying; my failure to adequately monitor the aircraft and automation caused this event. The beginning of descent was busy on this flight. We were finishing our crew meals; and still briefing the arrival when we began the descent. I do not recall exactly what I was doing at the moment we passed through FL290 (when I should have selected managed descent); but I was not focused enough on monitoring and controlling the aircraft. It was the last leg of a long day (3 legs with 3 different aircraft; 7 hours flying; and an Operating Experience flight with a check airman). I was tired and concerned with operating into DFW as I have only been there a few times; and not at all recently. Fly the aircraft. As Pilot Flying; my main focus should have been on controlling the flight path of the airplane. If I needed to focus elsewhere; I should have handed control over to the other pilot.
Air carrier pilot reported an altitude overshoot due to automation mismanagement.