Narrative:

Aircraft descended below approach chart MSA altitude at krain on the ILS runway 25L approach; los angeles; ca. Pilot monitoring called altitude deviation. Pilot flying engaged dec mode; aircraft leveled off and reestablished descent profile. After passing riivr at 12;000 ft; an approach clearance for ILS runway 25L was received. The FMGC was previously set up for an ILS 24R and the late approach procedure change required the pilot monitoring to be heads down activating the secondary flight plan; and inserting approach performance data n the mcdu. Pilot flying selected FAF crossing altitude without pushing the FCU altitude selector and vertical guidance reverted to vertical speed mode due to altitude mode engagement immediately before lower altitude selection. (Pilot flying stated '2000 blue' after resetting the FCU altitude and neither pilot realized the statement should have been '9000 magenta'). This reversion resulted in loss of dec mode; crossing restriction compliance and subsequent altitude deviation at krain. ATC did not acknowledge the altitude deviation. 1) remove the requirement to call operations in range for gate assignments and specials. (ACARS provides gate information and stations convey passenger specific needs.) 2) encourage use of the rotate chart feature of the efb to display the large lax approach chart clearly. 3) train magenta altitude callouts passing each intersection on a STAR with descend via or early approach clearances. 4) avoid setting FCU altitudes below altitude restrictions in descent. This; however; would create additional vertical speed revisions. 5) turn off speakers in descent. Speaker noise with headsets on; contributed to missing vertical mode reversion chine. 6) push the FCU altitude selector after selecting every new altitude to maintain dec mode vertical guidance and reset undesired vertical speed mode reversion. 7) refrain from changing database crossing altitude restriction information as a technique to refine aircraft descent path. This diverted pilot flying's attention to efb terminal charts to confirm and crosscheck restrictions and contributed to the event. 8) ATC assigning landing runway on initiation of STAR would reduce pilot monitoring's workload in critical approach phase. 9) emphasize monitoring of vdev symbol during secondary flight plan activation workload. 11) ATC should notify pilots of MSA deviations immediately if they are aware of the event.

Google
 

Original NASA ASRS Text

Title: An A320 flight crew on arrival to LAX descended below charted altitude at a fix following a runway change and improper vertical mode management.

Narrative: Aircraft descended below approach chart MSA altitude at KRAIN on the ILS Runway 25L approach; Los Angeles; CA. Pilot monitoring called altitude deviation. Pilot flying engaged DEC mode; aircraft leveled off and reestablished descent profile. After passing RIIVR at 12;000 FT; an approach clearance for ILS Runway 25L was received. The FMGC was previously set up for an ILS 24R and the late approach procedure change required the pilot monitoring to be heads down activating the secondary flight plan; and inserting Approach performance data n the MCDU. Pilot flying selected FAF crossing altitude without pushing the FCU Altitude selector and vertical guidance reverted to vertical speed mode due to Altitude mode engagement immediately before lower altitude selection. (pilot flying stated '2000 blue' after resetting the FCU altitude and neither pilot realized the statement should have been '9000 magenta'). This reversion resulted in loss of DEC mode; crossing restriction compliance and subsequent altitude deviation at KRAIN. ATC did not acknowledge the altitude deviation. 1) Remove the requirement to call operations in range for gate assignments and specials. (ACARS provides gate information and stations convey passenger specific needs.) 2) Encourage use of the Rotate chart feature of the EFB to display the large LAX approach chart clearly. 3) Train magenta altitude callouts passing each intersection on a STAR with descend via or early approach clearances. 4) Avoid setting FCU altitudes below altitude restrictions in descent. This; however; would create additional vertical speed revisions. 5) Turn off speakers in descent. Speaker noise with headsets on; contributed to missing vertical mode reversion chine. 6) Push the FCU altitude selector after selecting every new altitude to maintain DEC mode vertical guidance and reset undesired vertical speed mode reversion. 7) Refrain from changing database crossing altitude restriction information as a technique to refine aircraft descent path. This diverted pilot flying's attention to EFB Terminal charts to confirm and crosscheck restrictions and contributed to the event. 8) ATC assigning landing runway on initiation of STAR would reduce pilot monitoring's workload in critical approach phase. 9) Emphasize monitoring of VDEV symbol during secondary flight plan activation workload. 11) ATC should notify pilots of MSA deviations immediately if they are aware of the event.

Data retrieved from NASA's ASRS site as of April 2012 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.