Narrative:

This was day 7 of a 6 day trip. We had canceled the day before due to a defective L2 cockpit window. On that day; maintenance tried unsuccessfully to dispatch us with a blatantly defective window. I wrote a safety report on this. During that delay; we noticed and wrote up the fact that the number 4 hydraulic system showed low quantity (RF). Overnight; supposedly; maintenance serviced the system. Second indication of low hydraulic quantity. Today; on the continuation of the flight; we once again noticed the RF indication on hydraulic system 4 at the gate and wrote it up. The doors were closed at the time. I told the mechanic on the headset about it. He was ready to push us for departure. The conversation went something like this: me: hold the push; we have a low quantity indication on the number 4 hydraulic system. Mechanic: we serviced it yesterday. Me: its showing RF now and needs to be serviced. Mechanic: I think it's the gauge. We will defer it. Me: did you check the level? Mechanic: yes. Me: no; I mean right now. Is it full right now? Mechanic: (less than a minute later) yes. Me: we need a new maintenance release. Mechanic: ok hydraulic qty low 4 EICAS ; multiple hydraulic system 4 problems. We received the maintenance release and continued to depart. At about 500 ft on departure; we received a hydraulic qty low 4 EICAS message. Once at a safe altitude; I called maintenance to determine if this was associated with the quantity system deferral or a separate problem. After a lot of deliberation; it was decided that this was a separate problem and we accomplished the appropriate checklist. The checklist had us turn off the number 4 hydraulic system (only to be used on final approach). We now also had a hydraulic pressure demand 4 EICAS and a gear monitor EICAS message and a number 4 hydraulic system fault light illuminated. The number 4 hydraulic system was shutdown. Diversion airport weather poor. I checked the enroute and diversion airports and noticed that the weather was not good. I called dispatch and maintenance and expressed our concerns about continuing with the number 4 hydraulic system shutdown for the following reasons: 1) we were now down to 3 hydraulic systems. If we were to lose another; procedure would have us land at the nearest suitable airport. 2) there were now 3 separate faults in the number 4 hydraulic system. 3). The weather at some potential divert airports was poor. For these reasons and with extensive deliberation with maintenance; dispatch; and my crew; I decided that a precautionary divert was warranted in the interest of safety. Dispatch concurred and we began a divert. Diversion to ZZZZ1 airport; message incomplete errors increased workload no written release for divert. We had to get our own weather and our own clearance. This was greatly complicated by incomplete message errors (previously reported on several occasions). We never received a printed flight plan/release to ZZZZ1. I surmise that this was due to complications with getting a reroute; a continuing problem. Fuel dump microburst alerts. We had to dump about 140;000 pounds of fuel to max landing weight. We arrived in the terminal area only to find a major thunderstorm with microbursts exceeding 45 KTS. We had to hold for about 30-45 minutes for the weather. Had we had known of the deteriorating weather situation; we could have saved about 15-20;000 pounds of fuel which was dumped unnecessarily. We finally landed. There was no gate available; so we had to wait on the taxiway. While waiting; the station called us to advise that another aircraft reported that we were leaking oil; and to shut down the engines and await a mechanic. We did so and advised ATC. Medical problem. During the wait; the purser called and stated that a passenger was experiencing heart problems due to lack of medication. We relayed the urgency to get to the gate to the station; determined that there was no oil leak; restarted engines andtaxied to gate. Hydraulic quantity gauge appeared to be working as designed. Upon arrival; we queried the mechanic and found that the number 4 hydraulic quantity was approximately 50%; just as the now-deferred quantity system was indicating. We think the gauge was working properly; and that had ZZZZ maintenance serviced the system to full quantity prior to departure instead of rushing us out; we probably would not have experienced the low hydraulic quantity warning and would have continued without a need for a fuel dump; diversion; and subsequent cancellation. MEL item information maintenance procedures appear to have not been followed. After looking at the MEL item information associated with the deferral; it appears that departure airport maintenance did not perform the required steps contained therein; because for them to do so would have required reopening the aircraft doors; which they did not do. The flight crew is only provided the pilot requirements in the maintenance release and were unaware of the mechanic's requirements. History of similar faults. Also; a review of this aircraft's maintenance history revealed a robust history of hydraulic system 4 leaks and failures; one of which closely mirrored our failure. We were never advised of this history. Lack of maintenance oversight. In hindsight; this appears to have been an unnecessary divert; dump; and cancellation that can be attributed to departure airport maintenance rush to dispatch the aircraft; just as I reported. I have to ask once again; where is the regulatory and company oversight? Where is the FAA poi? Pilot pushing. After landing; we proceeded as directed. We called crew scheduling as directed and were told that we would be flying another aircraft in about 2.5 hours. We advised crew scheduling that this would exceed our maximum duty time by about an hour or more and that we were not agreeable. We were exhausted at this point; the full crew having had to run checklists and deal with irregularities; a divert; a dump; etc.; for the entire last leg. For the next 3 hours; my crew was constantly bombarded and harangued by flight operations management; including the chief pilot; to continue by extending our duty day past the limit. The pressure to continue was greatest on the copilots. The chief pilot even told two of them to 'man up.' had they capitulated; I calculated that their duty day would have approached 23 hours. This; in my opinion; would have been an unsafe operation.

Google
 

Original NASA ASRS Text

Title: A B747-400 flight crew enumerated a plethora of issues associated with a planned transpacific flight including: the failure of a chronically recalcitrant hydraulic system specifically declared fixed by Maintenance just prior to departure; maintenance anomalies; a diversion to an airport impacted by severe weather; inadequate weather; flight planning and general Dispatch assistance; a passenger complaining of heart problems; schedule pressure as management attempted to extend their duty day to as much as 23 hours.

Narrative: This was day 7 of a 6 day trip. We had canceled the day before due to a defective L2 cockpit window. On that day; Maintenance tried unsuccessfully to dispatch us with a blatantly defective window. I wrote a safety report on this. During that delay; we noticed and wrote up the fact that the number 4 hydraulic system showed low quantity (RF). Overnight; supposedly; Maintenance serviced the system. SECOND INDICATION OF LOW HYDRAULIC QUANTITY. Today; on the continuation of the flight; we once again noticed the RF indication on hydraulic system 4 at the gate and wrote it up. The doors were closed at the time. I told the Mechanic on the headset about it. He was ready to push us for departure. The conversation went something like this: me: hold the push; we have a low quantity indication on the number 4 hydraulic system. Mechanic: we serviced it yesterday. Me: its showing RF now and needs to be serviced. Mechanic: I think it's the gauge. We will defer it. Me: did you check the level? Mechanic: yes. Me: no; I mean right now. Is it full right now? Mechanic: (less than a minute later) Yes. Me: we need a new Maintenance Release. Mechanic: OK HYD QTY LOW 4 EICAS ; MULTIPLE HYD SYSTEM 4 PROBLEMS. We received the Maintenance Release and continued to depart. At about 500 FT on departure; we received a HYD QTY LOW 4 EICAS message. Once at a safe altitude; I called Maintenance to determine if this was associated with the quantity system deferral or a separate problem. After a lot of deliberation; it was decided that this was a separate problem and we accomplished the appropriate checklist. The checklist had us turn off the number 4 hydraulic system (only to be used on final approach). We now also had a HYD PRESSURE DEMAND 4 EICAS and a GEAR MONITOR EICAS message and a number 4 hydraulic system fault light illuminated. The number 4 hydraulic system was shutdown. DIVERSION AIRPORT WEATHER POOR. I checked the enroute and diversion airports and noticed that the weather was not good. I called Dispatch and Maintenance and expressed our concerns about continuing with the number 4 hydraulic system shutdown for the following reasons: 1) We were now down to 3 hydraulic systems. If we were to lose another; procedure would have us land at the nearest suitable airport. 2) There were now 3 separate faults in the number 4 hydraulic system. 3). The weather at some potential divert airports was poor. For these reasons and with extensive deliberation with Maintenance; Dispatch; and my crew; I decided that a precautionary divert was warranted in the interest of safety. Dispatch concurred and we began a divert. DIVERSION TO ZZZZ1 Airport; MESSAGE INCOMPLETE ERRORS INCREASED WORKLOAD NO WRITTEN RELEASE FOR DIVERT. We had to get our own weather and our own clearance. This was greatly complicated by incomplete message errors (previously reported on several occasions). We never received a printed flight plan/release to ZZZZ1. I surmise that this was due to complications with getting a reroute; a continuing problem. FUEL DUMP MICROBURST ALERTS. We had to dump about 140;000 LBS of fuel to max landing weight. We arrived in the terminal area only to find a major thunderstorm with microbursts exceeding 45 KTS. We had to hold for about 30-45 minutes for the weather. Had we had known of the deteriorating weather situation; we could have saved about 15-20;000 LBS of fuel which was dumped unnecessarily. We finally landed. There was no gate available; so we had to wait on the taxiway. While waiting; the station called us to advise that another aircraft reported that we were leaking oil; and to shut down the engines and await a Mechanic. We did so and advised ATC. MEDICAL PROBLEM. During the wait; the purser called and stated that a passenger was experiencing heart problems due to lack of medication. We relayed the urgency to get to the gate to the station; determined that there was no oil leak; restarted engines andtaxied to gate. HYDRAULIC QUANTITY GAUGE APPEARED TO BE WORKING AS DESIGNED. Upon arrival; we queried the Mechanic and found that the number 4 hydraulic quantity was approximately 50%; just as the now-deferred quantity system was indicating. We think the gauge was working properly; and that had ZZZZ Maintenance serviced the system to full quantity prior to departure instead of rushing us out; we probably would not have experienced the low hydraulic quantity warning and would have continued without a need for a fuel dump; diversion; and subsequent cancellation. MEL ITEM INFO MAINTENANCE PROCEDURES APPEAR TO HAVE NOT BEEN FOLLOWED. After looking at the MEL item information associated with the deferral; it appears that departure airport Maintenance did not perform the required steps contained therein; because for them to do so would have required reopening the aircraft doors; which they did not do. The flight crew is only provided the pilot requirements in the Maintenance Release and were unaware of the Mechanic's requirements. HISTORY OF SIMILAR FAULTS. Also; a review of this aircraft's maintenance history revealed a robust history of hydraulic system 4 leaks and failures; one of which closely mirrored our failure. We were never advised of this history. LACK OF MAINTENANCE OVERSIGHT. In hindsight; this appears to have been an unnecessary divert; dump; and cancellation that can be attributed to departure airport Maintenance rush to dispatch the aircraft; just as I reported. I have to ask once again; where is the regulatory and company oversight? Where is the FAA POI? PILOT PUSHING. After landing; we proceeded as directed. We called crew scheduling as directed and were told that we would be flying another aircraft in about 2.5 hours. We advised crew scheduling that this would exceed our maximum duty time by about an hour or more and that we were not agreeable. We were exhausted at this point; the full crew having had to run checklists and deal with irregularities; a divert; a dump; etc.; for the entire last leg. For the next 3 hours; my crew was constantly bombarded and harangued by flight operations management; including the Chief Pilot; to continue by extending our duty day past the limit. The pressure to continue was greatest on the copilots. The Chief Pilot even told two of them to 'man up.' Had they capitulated; I calculated that their duty day would have approached 23 hours. This; in my opinion; would have been an unsafe operation.

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.