B767 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 120; Flight Crew Total 10000; Flight Crew Type 3000
Confusion
No Specific Anomaly Occurred All Types
Air Traffic Control Issued New Clearance
Human Factors
During flight planning the flight plan indicated the flight would depart on time; but arrive 1:11 late.  We assumed it was due to an unusually long NAT track and unfavorable winds.  The flight plan called for a cost index of 149.  After loading and verifying the flight plan in the FMS; we compared the FMC distance to that of the flight plan; and they matched.  I had the 3rd break.  I was called back to the cockpit an hour early and told that we were arriving on time; and with 10;000 lbs more fuel than expected.  While on break; the flight had been cleared direct to a point ahead; which reduced the flight time by nearly 1 hour.  We landed on time.  The next morning I studied the flight plan to try and figure out what happened.  That's when I noticed two points that took us nearly 90 degrees off course for 350 miles; then 180 turn back to a normal course.  The route went Bexet; Lasno; Emper; Unlid.  I assume the controller must have noticed the unusual route and when the flight was cleared direct to Unlid; about an hour was knocked off the flight time; along with 10;000lbs of fuel savings.
During pre-flight a B767 crew notice an unusually high flight time for their North Atlantic crossing.  Later on during coast in ATC reclears the flight on a route reducing flight time by approximately 1 hour.  Reporter later researches the longer planned flight and finds the original route was filed incorrectly with a zig zag type pattern to the south and west of Ireland.