Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Fuel Issue
General Maintenance Action
Aircraft
Prior to Equal Time Point (ETP) we had about a 1;200 pound fuel imbalance; right side low; so we cross fed. Then shortly after that we noticed that the right side was getting low again. About 2 minutes prior to ETP we got the FMC message; FUEL QTY ERROR-PROG 2 [and] we noticed the difference between totalizer and calculated on the FMC was about 3;000 LBS which happened really fast. QRH has you go to the ENGINE FUEL LEAK checklist. Part of this checklist states; if you have a fuel imbalance of 1;000 pounds or more within a 30 minute time frame; you should assume that you have a leak and you should shut down that engine. We had 800 pounds in 30 minutes. I had [the First Officer] go back to see if he could see a leak; he said maybe a little mist; but couldn't tell if it was just a faint contrail; he said other side looked about the same. The imbalance stabilized at around 1;500 to 1;700 pounds and fuel at destination continued to show 16.3. Fuel remaining was decreasing also; but not real dramatically. At our last waypoint we were -1.8. We started our descent into [destination]; and while descending; the imbalance started to increase again; the difference was about 3;200 pounds at one point.Right after parking and shutting down the engines; the flight attendant called to tell us that there was a heavy fuel smell coming from the back. Maintenance came up to the cockpit and told us that there was a bunch of fuel coming out of our right engine. We went down to take a look and one of the ramp guys came over to tell us that as we were taxiing in; he noticed a bunch of liquid coming from our right engine; but thought it just might be condensation. He said the fuel leak stopped once we shut the engine down. Fuel leak; right engine.
B767-300 Captain reported a fuel imbalance and FMC message FUEL QTY ERROR-PROG 2 on a trans-oceanic flight. After parking at the gate; ramp personnel reported a significant fuel leak from the right engine.