B737-800
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Conflict Airborne Conflict
General None Reported / Taken
Human Factors; Airspace Structure
While being vectored through ONT LOC 26R approach course for spacing from other airline traffic; a large drone was spotted in close proximity to our jet. We were heading roughly north at 6000 ft. The drone was about 500 feet below and 100 to 200 yards to our left. Looking on google map; it was approximately at the intersection of highway 215 and 10 near a golf course. This was immediately reported to ONT approach control (SOCAL). I was the only one that saw it from our cockpit. FO was flying. The drone was large; appeared to be a four or more engines; and about three feet in diameter. Looked like two tone dark and light color. Maybe blue and white or green and white. Watched for about 4 to 7 seconds as we passed it.
B737 Captain reported sighting a large drone while being vectored for an instrument approach near ONT.