"We were scheduled to fly from South Korea to Alaska. We were carrying 200 passengers onboard a B767-300. The route would take us over the Pacific Ocean on a 7 hour flight. We were dispatched as an ETOP's flight with Saporo, Japan as our first ETOPS alternate and the Aleutian islands of the coast of Alaska as our second ETOPS alternate.
The crew was composed of 3 pilots (2 FO's and 1 CA), 9 FA’s and 2 mechanics. I was designated as the relief pilot and upon reaching the top of climb, I was told to get some rest.
Slightly 3 hours after takeoff, a flight attendant came to wake me up. I thought it was time for a crew change. Once I got into the cockpit, I realized that something was wrong. Both pilots had their checklists out. I was immediately made aware of the problem. The aircraft was indicating a lost of over 60% of engine oil off the left engine in less than 10 minutes. There was no EAICAS message about it and no other anomaly in engine parameters. The Captain requested the two mechanics onboard to be waken up and brought to the cockpit. When they showed up, we explained the situation and asked for their inputs. They replied that it was "not good”...obviously!
We then called dispatch and maintenance control over the satellite phone while we worked our checklists and briefed the Flight Attendants. Maintenance control was of no help either. Having water in all quadrants was of course nerve racking. The thought of an engine failure in the middle of the Pacific wakes you up pretty quickly. We were fast approaching our Equal Time Point (ETP) and the idea of diverting to the Aleutian islands was not the best option. Time was becoming critical so I finally spoke up “We need to do a 180 and go to Japan!”. Everyone looked at each other and we all agreed. However, instead of Saporo as our diversion airport we decided with dispatch to go to Misawa Air Base in the Northeast coast of Japan.
Japanese people are very structured and disciplined but their English is very limited. When we showed up in their airspace, we had to explain multiple times why we were there and what our intentions were. The Captain was getting really frustrated so he asked me to bypass all those controllers and to contact directly Misawa Air Base tower as soon as we were within VHF range. Once more, I ended up talking to a clearly confused Japanese controller. I suddenly remembered, from a previous experience years ago, that the ground frequency at this airport is always manned by US personnel. I switched frequency and the accent of a southern boy was clear in a million.
We explained our situation, got priority handling and landed without incident. After landing, we all got off the plane to look at the engine. We made the right call. Oil was everywhere! The engine had lost a ton of oil. We spent 24 hours in Japan before the problem was fixed and we continued our journey home."