Narrative:

Arrival into dubai was darax 3A and was uneventful until talvi. Approach had brought another airplane over talvi 2;000 ft below us and was about 1/2-1 mile in front of us. He cleared us to descend from 6;000 to 4;000. We told approach that we had traffic at 12 o'clock and he said we were going to follow him. As we started descent; the previous plane turned base leg and we continued toward alnet. He then gave us a 210 heading; followed shortly by a 140 heading and descent from 4;000-2;000. I selected flch and speed brakes to get us on down to 2;000 since approach was getting rushed. He then cleared us the RNAV 12L approach. He also told us to slow to final approach speed. The 140 heading was going to put us just outside of DB601 FAF. After cleared; and established on final; and protected in FMS; I selected LNAV and selected 570 (561) in MCP altitude window. I then mistakenly pushed app. I was still slowing with boards and descending. If I'd selected VNAV we would've been truly protected to 2;000 till DB601. By selecting app; I had taken out the 2;000 protection. With letting myself get rushed and trying to slow I descended several hundred feet below the planned path of 2;000 ft. My first officer said we were low and I disconnected the autopilot and climbed to 2;000 just by DB601. I reconnected the autopilot and continued approach to landing. ATC seemed to be trying to rush us and I let them; which led to me making errors. I also just finished HUD training; and I think that added a little extra distraction. Not trying to put blame on ATC or HUD; just pointing out possible factors that could've contributed. I could've not let ATC put us so close to other plane which caused us to slow down while trying to get down. Should've just had them extend our downwind leg. Obvious selecting app instead of VNAV is primary reason of breakdown. Turning off HUD/EFIS would've eliminated an unnecessary distraction.

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Original NASA ASRS Text

Title: A widebody crew on the OMDB RNAV Runway 12L became rushed attempting to slow and descend behind traffic. The Captain selected APP while descending to the 2;000 FT FAF crossing constraint and the busy First Officer detected the aircraft descending at 1;200 FT prior to the FAF and alerted the Captain who climbed to 2;000 FT.

Narrative: Arrival into Dubai was DARAX 3A and was uneventful until TALVI. Approach had brought another airplane over TALVI 2;000 FT below us and was about 1/2-1 mile in front of us. He cleared us to descend from 6;000 to 4;000. We told Approach that we had traffic at 12 o'clock and he said we were going to follow him. As we started descent; the previous plane turned base leg and we continued toward ALNET. He then gave us a 210 heading; followed shortly by a 140 heading and descent from 4;000-2;000. I selected FLCH and speed brakes to get us on down to 2;000 since approach was getting rushed. He then cleared us the RNAV 12L Approach. He also told us to slow to final approach speed. The 140 heading was going to put us just outside of DB601 FAF. After cleared; and established on final; and protected in FMS; I selected LNAV and selected 570 (561) in MCP ALT window. I then mistakenly pushed APP. I was still slowing with boards and descending. If I'd selected VNAV we would've been truly protected to 2;000 till DB601. By selecting APP; I had taken out the 2;000 protection. With letting myself get rushed and trying to slow I descended several hundred feet below the planned path of 2;000 FT. My First Officer said we were low and I disconnected the autopilot and climbed to 2;000 just by DB601. I reconnected the autopilot and continued approach to landing. ATC seemed to be trying to rush us and I let them; which led to me making errors. I also just finished HUD training; and I think that added a little extra distraction. Not trying to put blame on ATC or HUD; just pointing out possible factors that could've contributed. I could've not let ATC put us so close to other plane which caused us to slow down while trying to get down. Should've just had them extend our downwind leg. Obvious selecting APP instead of VNAV is primary reason of breakdown. Turning OFF HUD/EFIS would've eliminated an unnecessary distraction.

Data retrieved from NASA's ASRS site 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.