B747-400 Captain refused the aircraft assigned to his flight because of long term deferral of landing gear retraction mechanism requiring the routine use of an irregular procedure to retract the landing gear.

Narrative

I am writing this report to bring to your attention what I believe to be potentially illegal and unsafe maintenance action and procedures. Approximately 24 hours prior to the flight; as is my normal practice; I checked the maintenance status of the aircraft that was planned for our flight. I noticed a deferral for the landing gear latch solenoid. The original problem was a Gear Disagree EICAS advisory message; indicating that the gear was not in the selected position. The crew reported that the gear could not be raised normally; the handle was locked and could not be raised beyond the 'off' (middle) position. The crew recycled the gear but still could not raise the gear without engaging the 'Gear Override' system. Maintenance subsequently deferred the landing gear latch solenoid; which allowed the aircraft to continue. The MEL item card associated with this deferral instructs the crew to retract the landing gear using the Flight Manual Irregular Procedure. The aircraft has been flying around in this condition without any documented maintenance action. Discussion with System Maintenance on the day prior to the flight; I called System Maintenance to discuss this problem about 16 hours prior to the flight and asked the following: 1) the basis for the deferral of the landing gear latch solenoid; 2) what troubleshooting had been done and what was planned to be done; 3) about any safety implications surrounding the deferral; and 4) what backup systems were available to the crew in the event that a subsequent failure would cause the Gear Disagree EICAS message to appear. He did not know the basis for the specific reason for deferring the latch solenoid and was unaware of any troubleshooting that had been performed. We discussed the potential problems that might result as a result of the crew forcing the retraction of the landing gear if the tilt mechanism were to fail. Time and parts available but still no troubleshooting. Upon arrival at the airport this morning; I called System Maintenance through dispatch to discuss the deferral. All involved were surprised that the issue had not been addressed. No action on this item was performed overnight; as I was told would be the case. This deferral occurred in March/2009. Up to now; there have been several opportunities to troubleshoot the problem but none has been done; according to the Maintenance Controller. Parts have been available in ZZZ since March/2009 according to Maintenance Computer Log. The Maintenance Controller was astonished himself that no troubleshooting had been done to date. I discussed this problem with my crew; and we all remained very concerned about the potential safety implications of the deferral; and secondarily; the basis for the deferral itself and the lack of any maintenance action since the original in March/2009. With dispatch and maintenance concurrence; we made a plan to go out to the aircraft and discuss the problem with maintenance. I wanted to know why the landing gear latch solenoid was deferred and what troubleshooting had been accomplished. If we could be assured that the latch solenoid was; in fact; at fault; I told dispatch and maintenance that I would accept it. We went to the aircraft and I spoke with a Line Mechanic and the Maintenance Supervisor. Neither could answer either of my questions. No troubleshooting had been done ('no parts;' not true according to Maintenance Computer Log); the gear had not been 'slugged' (sensors tested). The Mechanic also told us that he thought that the gear sensors were at fault. However; this was not what was deferred. The Maintenance Supervisor also tried to convince us that the fault had not recurred. His basis for this was that no subsequent write-ups had been made. I tried; unsuccessfully; to explain to him that crews are not required; and rarely do; write up items that already have been deferred and; thus; we have no idea whether or not the fault has recurred. Aircraft refusal as a result of not being able toascertain any further information that would satisfy our safety concerns; I declined to accept the deferred item in accordance with the FAR and FOM guidance because the safety of the flight and the legality of the deferral could not be assured. My entire crew strongly supported this decision as did our Dispatcher. Dispatch also advised me that they were entering a dispatch refusal as well. We are concerned about the basis for deferring the landing gear latch solenoid with little or no troubleshooting. According to maintenance; Maintenance Computer Log history indicates a history of gear problems with this aircraft. I checked the Onboard Central Maintenance Computer (CMC) and found a fault with the Left Main Landing Gear Tilt Proximity Switch. I remain concerned that the original fault 'GEAR DISAGREE' may have resulted from the failure of this tilt proximity switch; and that the landing gear system was properly warning the crew NOT to retract the gear to prevent potential serious damage to the aircraft if the gear is not in the proper tilt position for retraction. What basis was used by ZZZZ Maintenance to determine that the landing gear latch solenoid was at fault and what troubleshooting was done prior to this deferral. I notice in Maintenance Computer Log that maintenance now suspects harness damage or a tilt actuator. Requirement to use a Flight Manual Irregular Procedure to satisfy MEL deferral requirements I am also concerned about the rationale for allowing a deferral which requires the flight crew to perform a Flight Manual Irregular Procedure on a continual basis to allow the aircraft to continue to fly with a deferred item. The Maintenance Controller urged me to bring this to the company's attention; suggesting that this practice might be unwise and should be reviewed. Potential problems that could result from an engine failure I; as well as my entire crew; was most concerned about the implication of an engine failure during our heavyweight takeoff (approximately 800;000 LBS) at an airport with serious terrain in the departure corridor requiring a special engine-out procedure. If we were to experience an engine failure on takeoff; prompt retraction of the landing gear would be essential in order to meet the performance requirements needed to safely clear the terrain. We would not have sufficient time to refer to and perform the Flight Manual Irregular procedure to raise the landing gear; as would be required by this deferral. How are we relieved of the responsibility to perform irregular procedures by use of the flight manual? I can only surmise that the expectation is that I would have to exercise my Captain's emergency authority and direct the crew to perform the irregular procedure from memory. My understanding is that the use of Captain's emergency authority is intended to address unforeseen circumstances which might threaten the safety of the flight. The planned use of emergency authority would be inappropriate. We should not be planning flights on the basis of the expected use of a Captain's emergency authority. Dispatch not being made aware of aircraft maintenance status. Except for my call to maintenance on the day prior to the flight; I used dispatch for all my contacts with maintenance. Our Dispatcher was very helpful and supportive. He advised me that he had not known about this defect because it is not a dispatch related maintenance item. He stated that; had he been aware of the deferral by being provided a copy of the maintenance history; he could have looked into it sooner and possibly have prevented the delayed flight. I was surprised to learn that dispatchers are not provided the history; only dispatch maintenance items; yet they share the responsibility for the flight. This should be changed. Contact with management. After deplaning; I was contacted by Captain from the flight office. He wanted to hear my explanation. I explained our rationale and what had transpired. He stated that he was satisfied w