B777 Undifferentiated or Other Model
Flight Crew Last 90 Days 250; Flight Crew Total 14500; Flight Crew Type 5000
Other / Unknown
Conflict NMAC
General None Reported / Taken
Human Factors
Approaching DOMSE on visual approach to [Runway] 19L at IAD; descending through 1;800 MSL an object was spotted at 12:30 position tracking straight on slightly below our altitude. As it passed by the right side of the aircraft approximately 100 FT and below our altitude by 100 FT it became apparent that it was a drone of some sort approximately 4 FT in diameter; saucer shaped; and gold or bronze in color. I made a comment to the other two pilots in the flight deck that it appeared to be a drone.  The Captain reported our sighting to the Tower and the rest of the approach was continued without incident.
[Report narrative contained no additional information]
B777 flight crew reports sighting a drone in IAD Class B airspace during approach.