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A late runway change on a STAR to lax resulted in an autoflight configuration error and a track deviation for a B737-300.
| Attributes | |
| ACN | 842469 |
| Time | |
| Date | 200907 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | SCT.TRACON |
| State Reference | CA |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Make Model Name | B737-300 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Descent |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | FMS/FMC |
| Person 1 | |
| Function | Captain |
| Experience | Flight Crew Last 90 Days 240 Flight Crew Type 10000 |
| Events | |
| Anomaly | Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy Deviation - Track / Heading All Types |
Narrative:
Within two miles of riivr intersection; ATC assigned runway 25L. We had previously selected and briefed 24R. The autopilot was on and the first officer selected the new runway from the database with the riivr transition. We reviewed the legs page; closed the discontinuity; and executed with riivr as the active waypoint. We were unaware that between execution and the review of the legs page; the aircraft flew past riivr intersection. Within 60 seconds; ATC said we were off the path and told us to go direct to dymmo intersection. Instantaneously we were able to see the autopilot was in cws roll. Also; krain intersection was at position 1L; but was not highlighted. We complied with the direct to clearance and completed the flight uneventfully. We complied with the company procedure for change of runway as far as selection and review; we neglected to see the active waypoint highlighted because LNAV had disengaged. I find this situation very challenging especially in a single CDU -300. The disengagement of LNAV is insidious; the warnings are a lack of reverse video on the CDU active waypoint and cws roll on the FMA. The fact that no big turn was associated with the change in clearance further masked the error. The map presentation of the -700 is a big help. Further; ATC should give us more time or accept separation responsibility via a vector.
Original NASA ASRS Text
Title: A late runway change on a STAR to LAX resulted in an autoflight configuration error and a track deviation for a B737-300.
Narrative: Within two miles of RIIVR intersection; ATC assigned Runway 25L. We had previously selected and briefed 24R. The autopilot was on and the First Officer selected the new runway from the database with the RIIVR transition. We reviewed the LEGS page; closed the discontinuity; and executed with RIIVR as the active waypoint. We were unaware that between execution and the review of the LEGS page; the aircraft flew past RIIVR intersection. Within 60 seconds; ATC said we were off the path and told us to go direct to DYMMO intersection. Instantaneously we were able to see the autopilot was in CWS Roll. Also; KRAIN intersection was at position 1L; but was not highlighted. We complied with the direct to clearance and completed the flight uneventfully. We complied with the company procedure for change of runway as far as selection and review; we neglected to see the active waypoint highlighted because LNAV had disengaged. I find this situation very challenging especially in a single CDU -300. The disengagement of LNAV is insidious; the warnings are a lack of reverse video on the CDU active waypoint and CWS roll on the FMA. The fact that no big turn was associated with the change in clearance further masked the error. The map presentation of the -700 is a big help. Further; ATC should give us more time or accept separation responsibility via a vector.
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.