B767-300 and 300 ER
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Distraction; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Overcame Equipment Problem; Flight Crew Returned To Clearance
Airspace Structure; Environment - Non Weather Related; Human Factors
During cruise flight approximately 50 to 60 miles east of fix and offset 5 NM right of course; as directed by ATC; [Ckeck Pilot] and I were discussing the procedures for approach and runway change going into ZZZ. I had selected the route 2 page; neither of us activated or executed the route 2. During the discussion Control called us and ask our position; and then we immediately noticed the aircraft in a slight left bank; approximately 20 degree bank; and our heading approximately 40 degrees of expected. PF (Pilot Flying) immediately slowed and selected a correction heading back to course. I estimate we erred off course 3 to 4 miles before correcting. I did not notice what the to waypoint was before we were recleared back to ZZZZZ. I am sure that we were in LNAV and correctly proceeding to ZZZZZ before the event.I am not sure if there was a failure of the navigation system but both [Pilot Flying/Check Pilot] and I were heads down too long discussing runway change procedures and not monitoring the aircraft and systems. More diligent aircraft monitoring by both crew members [was needed].
B767 Captain reported that the aircraft was briefly off course causing Center to alert the deviation.