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A B712 crew, in descent to hnl, experienced a hydraulic fluid loss which prompted the crew to lower the landing gear early.
| Attributes | |
| ACN | 559312 |
| Time | |
| Date | 200209 |
| Day | Wed |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | navaid : hnl.vortac |
| State Reference | HI |
| Altitude | msl single value : 7000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : hnl.tracon tracon : dab.tracon |
| Operator | common carrier : air carrier |
| Make Model Name | B717 (Formerly MD-95) |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other other vortac |
| Flight Phase | descent : approach |
| Route In Use | arrival : on vectors |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp pilot : flight engineer pilot : commercial pilot : multi engine pilot : instrument |
| Experience | flight time last 90 days : 70 flight time total : 10570 flight time type : 700 |
| ASRS Report | 559312 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Events | |
| Anomaly | aircraft equipment problem : critical non adherence : company policies other anomaly other |
| Independent Detector | atc equipment other atc equipment : efis - hyd r qty lo avent other flight crewa other flight crewb |
| Resolutory Action | other |
| Consequence | other |
| Supplementary | |
| Problem Areas | Aircraft |
| Primary Problem | Aircraft |
Narrative:
During descent into honolulu from hilo, hi, on the morning of sep/wed/02 at about XA10, we experienced a level 2 (hydraulic right quantity low) alert. After selecting the hydraulic page on our system display, we saw that the hydraulic quantity was dropping in the right hydraulic system. It appeared that the quantity was being lost rapidly, at that time we elected to lower the landing gear before we lost all of the fluid from the right system as that is the only system that pwrs the landing gear. After the gear was lowered, we pulled out the checklist and followed the procedure until it stated that we needed to use the emergency gear extension lever. This procedure did not seem necessary to us because the landing gear already indicated down and locked. Deploying the emergency gear extension lever only allows for the landing gear to free-fall down. It would have also opened and left open the main gear doors. Later in the checklist, the procedure calls for stowing the emergency gear extension lever if any quantify remains. The checklist procedure does not seem to allow for the landing gear to be down already as it was in our case. In the intro to our checklist section, it states that 'strict compliance with these procedures is mandatory.... However, since no procedure could allow for every situation or contingency, nothing contained herein is intended to take precedence over good pilot judgement.' I believe that we used this 'good pilot judgement' to not strictly follow the checklist item by item. If we had, the landing gear doors would have remained open on our landing and it would have been damaged. I believe that the checklist should be changed to allow for the possibility of the landing gear being down so that if this problem should occur in the future there will not be any uncertainty as to whether or not to disregard part of the checklist. I intend to discuss with our flight department to see if they also feel that the checklist should be changed.
Original NASA ASRS Text
Title: A B712 CREW, IN DSCNT TO HNL, EXPERIENCED A HYD FLUID LOSS WHICH PROMPTED THE CREW TO LOWER THE LNDG GEAR EARLY.
Narrative: DURING DSCNT INTO HONOLULU FROM HILO, HI, ON THE MORNING OF SEP/WED/02 AT ABOUT XA10, WE EXPERIENCED A LEVEL 2 (HYD R QUANTITY LOW) ALERT. AFTER SELECTING THE HYD PAGE ON OUR SYS DISPLAY, WE SAW THAT THE HYD QUANTITY WAS DROPPING IN THE R HYD SYS. IT APPEARED THAT THE QUANTITY WAS BEING LOST RAPIDLY, AT THAT TIME WE ELECTED TO LOWER THE LNDG GEAR BEFORE WE LOST ALL OF THE FLUID FROM THE R SYS AS THAT IS THE ONLY SYS THAT PWRS THE LNDG GEAR. AFTER THE GEAR WAS LOWERED, WE PULLED OUT THE CHKLIST AND FOLLOWED THE PROC UNTIL IT STATED THAT WE NEEDED TO USE THE EMER GEAR EXTENSION LEVER. THIS PROC DID NOT SEEM NECESSARY TO US BECAUSE THE LNDG GEAR ALREADY INDICATED DOWN AND LOCKED. DEPLOYING THE EMER GEAR EXTENSION LEVER ONLY ALLOWS FOR THE LNDG GEAR TO FREE-FALL DOWN. IT WOULD HAVE ALSO OPENED AND LEFT OPEN THE MAIN GEAR DOORS. LATER IN THE CHKLIST, THE PROC CALLS FOR STOWING THE EMER GEAR EXTENSION LEVER IF ANY QUANTIFY REMAINS. THE CHKLIST PROC DOES NOT SEEM TO ALLOW FOR THE LNDG GEAR TO BE DOWN ALREADY AS IT WAS IN OUR CASE. IN THE INTRO TO OUR CHKLIST SECTION, IT STATES THAT 'STRICT COMPLIANCE WITH THESE PROCS IS MANDATORY.... HOWEVER, SINCE NO PROC COULD ALLOW FOR EVERY SIT OR CONTINGENCY, NOTHING CONTAINED HEREIN IS INTENDED TO TAKE PRECEDENCE OVER GOOD PLT JUDGEMENT.' I BELIEVE THAT WE USED THIS 'GOOD PLT JUDGEMENT' TO NOT STRICTLY FOLLOW THE CHKLIST ITEM BY ITEM. IF WE HAD, THE LNDG GEAR DOORS WOULD HAVE REMAINED OPEN ON OUR LNDG AND IT WOULD HAVE BEEN DAMAGED. I BELIEVE THAT THE CHKLIST SHOULD BE CHANGED TO ALLOW FOR THE POSSIBILITY OF THE LNDG GEAR BEING DOWN SO THAT IF THIS PROB SHOULD OCCUR IN THE FUTURE THERE WILL NOT BE ANY UNCERTAINTY AS TO WHETHER OR NOT TO DISREGARD PART OF THE CHKLIST. I INTEND TO DISCUSS WITH OUR FLT DEPT TO SEE IF THEY ALSO FEEL THAT THE CHKLIST SHOULD BE CHANGED.
Data retrieved from NASA's ASRS site as of July 2007 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.