 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
B787 captain reported that the auto load function for engine thrust settings was acting improperly and required a manual override.
| Attributes | |
| ACN | 1351196 |
| Time | |
| Date | 201604 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | ZZZZ.Airport |
| State Reference | FO |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Make Model Name | B787-800 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Parked |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | PMC Performance/Thrust Management Computer |
| Person 1 | |
| Function | Captain Pilot Not Flying |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Events | |
| Anomaly | Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy |
Narrative:
During pre-flight; the FMC uplinked takeoff data for runway 01. After receiving tps (takeoff performance system); runway 19 was selected and uploaded. When checking the uplinked FMC data for runway 19 against the tps; the FMC thrust setting showed to at a 38 degree derate vs the tps which showed to 1 with no derate. Furthermore; the thrust reduction altitude input of 1500 ft had changed to 1000 ft. Everything else matched the tps.the crew discussed this odd occurrence; manual inputs to correct FMC to match the tps and noise abatement data were made; and crew planned a coordinated check of uplinked takeoff data after receiving load closeout data. After receiving the post closeout uplink the same data appeared on the thrust page (to with 38 degree derate) and takeoff thrust reduction (changed to 1000 ft). Thinking perhaps something had changed since the original tps was printed; we requested a new tps via ACARS using the current ATIS information. The new tps matched the original; so manual changes were made once again to the FMC to match the tps and to correct thrust reduction altitude. No further discrepancies occurred. Both the fb and fc have seen this anomaly before on both 787 and 777.
Original NASA ASRS Text
Title: B787 Captain reported that the auto load function for engine thrust settings was acting improperly and required a manual override.
Narrative: During pre-flight; the FMC uplinked takeoff data for runway 01. After receiving TPS (Takeoff Performance System); runway 19 was selected and uploaded. When checking the uplinked FMC data for runway 19 against the TPS; the FMC thrust setting showed TO at a 38 degree derate vs the TPS which showed TO 1 with no derate. Furthermore; the thrust reduction altitude input of 1500 ft had changed to 1000 ft. Everything else matched the TPS.The crew discussed this odd occurrence; manual inputs to correct FMC to match the TPS and noise abatement data were made; and crew planned a coordinated check of uplinked takeoff data after receiving load closeout data. After receiving the post closeout uplink the same data appeared on the thrust page (TO with 38 degree derate) and takeoff thrust reduction (changed to 1000 ft). Thinking perhaps something had changed since the original TPS was printed; we requested a new TPS via ACARS using the current ATIS information. The new TPS matched the original; so manual changes were made once again to the FMC to match the TPS and to correct thrust reduction altitude. No further discrepancies occurred. Both the FB and FC have seen this anomaly before on both 787 and 777.
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.