UAL3921
- Airline
- United Airlines (UAL)
- Route
- San Francisco International Airport (SFO/KSFO) →
- Observed take-off
- Last heard
- Aircraft
- N771UA · BOEING 777-200
- Positions recorded
- 1281 As of 2026-10-17 19:37 UTC
Source: observations by the map.flights community network of ADS-B receivers; times in UTC.