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MD11 captain experiences the failure of the number two hydraulic system due to fluid loss. Flight continues to destination where a firm landing occurs. Reporter followed flight director flare command precisely and believes the system did not take into account the hydraulic failure and the resulting reduced elevator rate.
| Attributes | |
| ACN | 1068802 |
| Time | |
| Date | 201302 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | ZZZ.ARTCC |
| State Reference | US |
| Aircraft 1 | |
| Make Model Name | MD-11 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Climb |
| Component | |
| Aircraft Component | Hydraulic Main System |
| Person 1 | |
| Function | Captain Pilot Flying |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Events | |
| Anomaly | Aircraft Equipment Problem Less Severe |
Narrative:
Twenty seven minutes after takeoff the number 1 autopilot kicked off due to a loss of quantity and pressure in the number 2 hyd system. We accomplished all QRH items and continued to scheduled landing. The only additional item of note with the incident was a firm landing. I used the HUD 'flare command' very accurately but the resulting landing was harder than expected. With the loss of some elevator authority due to the loss of the number 2 hyd I am concerned that the feedback loop for the HUD display is only a mirror of the output from the FCC and not an accurate depiction of what the flight controls are doing. In other words I think the elevator may have been operating at some reduced rate and the flare command was presenting accurate info for a fully operational hyd system and elevator; which we didn't have today.
Original NASA ASRS Text
Title: MD11 Captain experiences the failure of the number two hydraulic system due to fluid loss. Flight continues to destination where a firm landing occurs. Reporter followed flight director flare command precisely and believes the system did not take into account the hydraulic failure and the resulting reduced elevator rate.
Narrative: Twenty seven minutes after takeoff the Number 1 Autopilot kicked off due to a loss of quantity and pressure in the Number 2 Hyd System. We accomplished all QRH items and continued to scheduled landing. The only additional item of note with the incident was a firm landing. I used the HUD 'flare command' very accurately but the resulting landing was harder than expected. With the loss of some Elevator Authority due to the loss of the Number 2 Hyd I am concerned that the feedback loop for the HUD display is only a mirror of the output from the FCC and not an accurate depiction of what the flight controls are doing. In other words I think the Elevator may have been operating at some reduced rate and the flare command was presenting accurate info for a fully operational Hyd System and Elevator; which we didn't have today.
Data retrieved from NASA's ASRS site as of July 2013 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.