Date: 201712
Local time of day: 1801-2400
Location: ZZZ.ARTCC, US
Flight conditions: VMC
Aircraft: A319
Operator: Air Carrier
Flight plan: IFR
Mission: Ferry / Re-Positioning
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Fuel Distribution System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Confusion; Time Pressure; Workload; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Landed As Precaution; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Aircraft; Company Policy; MEL
Primary problem: Ambiguous

Narrative: Aircraft was late and upon arrival my first impression was why are we flying an A319 coast to coast? Flight delayed one hour due to weight and balance. 41000 pounds of fuel were loaded on Aircraft X with 146 passengers. We had an MEL for one center tank pump #2. My thought then was can one center tank pump handle all that fuel. It took an hour of moving people; kids; bags and counting half weights to finally get a solution for takeoff. First; ramp folks improperly filled out load sheet filling in weights for bins that clearly stated only for 320/321 when we were in a 319. This led to a new form fill out after multiple negative solution requests in the box and finally a call to dispatch and load planning. When putting 41k pounds of fuel on a 319; some form of guidance and/or oversight must be given to ramp folks loading the aircraft; it was not and we paid the price. We took off. Climbout was uneventful and we reached cruise altitude without incident. About an hour and a half into the flight we received an ECAM for Fuel Auto Feed fault. We proceeded to methodically go through memory items; the ECAM itself and the QRH. The ECAM was telling us to turn on the #2 center tank pump which we could not do since it was MEL'd to keep off. We proceeded at that point to the MEL operational procedures which I'm going to say up front here are very poorly written and hard to understand. If you read the steps and follow the indents there is no clear; logical flow to what should be done and more importantly when. That has to be left for a separate conversation...too much detail for this incident report. See bottom for increased details.The bottom line was that by the time we did get to this; the left side was over 12k pounds and the right side was under 10k pounds with nearly 9k pounds in the sump. The procedure gave us two separate; conflicting actions for the two situations we had. It was very difficult to clearly discern a course of action. I also did not like the fact that not only were we flying an aircraft that was not perfectly suited for the flight; but the operational procedures appeared aimed at 'tricking' the system into working. These two factors again made me uncomfortable. The left side fuel was not flowing...period. The right side was draining faster than the sump. None of this made any sense but it became apparent that in a very short period of time we were going to have a major fuel split. I also opened the crossfeed valve and secured the #2 engine fuel pumps in the hopes of then draining left side fuel. NO fuel would transfer from the left side...period. There was no way we could even consider pressing on; a divert was imminent. I then contacted maintenance and explained the situation. They never even mentioned or asked about the operational procedures. We were directed to return to [Departure Airport]; however; when I mentioned we were already over halfway across and [an alternate] was 150 miles off the nose ie. much closer; we were then directed to go there. At that point we proceeded to divert while setting up the arrival and reviewing the QRH for overweight landing as we were close to 14k pounds overweight at landing (approximately 151k pounds). Uneventful landing around 300 FPM. We landed with nearly a 6000 pound fuel split. You could feel the wing dip on the left side and rudder trim was pushing 4.0 degrees. I never saw the need for declaring an emergency so we never did. At the gate we had the passengers deplane and maintenance started working the problem.Fuel was transferred manually and the split eliminated but no one ever could pinpoint why this happened. I was extremely leery of taking this aircraft up again. The maintenance guy said the refueling panel had a center tank pump switch in the open position. I don't know if this had any effect on the situation; it is my understanding that once the refueling panel is closed; it is rendered inoperative? Not one but two maintenance personnel were extremely curious as to why so much fuel was put on a 319 with one center tank pump inoperative? I agreed whole heartedly and really beat myself up for not pushing the issue prior to departing [Departure Airport]. It did not feel right to me. One of those maintenance guys said he did not feel that the single center tank pump could handle that much fuel. That aircraft was perfect for east coast flights. Low sump if any fuel and wing tank fuel only. Going to [Original Destination Airport] was a mistake in my eyes.This was why I did not want to take the aircraft up again for [Original Destination Airport]. After multiple discussions with crew schedulers and the Chief Pilot; I called in fatigued as we had been on the ground for near three hours. A plan was discussed to move all the remaining sump fuel to the wing tanks and fly to [another airport] where a new crew/aircraft would fly the people on to [Original Destination Airport]. I was willing to do this to help out the situation but crew schedulers said if you're too fatigued to fly to [the Destination Airport] then you are too fatigued to fly to [a connecting airport]. We agreed to disagree at that point and we left for the hotel. We had flown the redeye the previous evening and had minimal rest prior to [the Destination Airport]. I was tapped out by the entire evolution.This morning we repo'd Aircraft X back to via ferry flight. Had no issue with a light sump load of less than 2;000 pounds. No ECAMs; and although we did develop a fuel split of over 2;000 pounds; the sump tank bled down normally and the split over time corrected itself somewhat. I'm no maintenance guy but I feel it was the heavy sump load and one center tank pump inoperative that led to these issues. I'm hoping an answer can be provided.As a side note; the Flight Attendant (FA) crew said they had been on the same aircraft previously and had to do the same thing....divert for inoperative fuel transfer.




Synopsis: A319 Captain reported a serious fuel imbalance issue which could not be resolved in flight. A diversion to a nearby suitable airport was successfully accomplished.