United Airlines outlines top 10 long-distance Boeing 737-800 routes from San Francisco

Another noteworthy disjoint route involves Dallas/Fort Worth International Airport, at 1,464 miles away. United organizes 60 round trips between San Francisco and Dallas, inclusive of a one-time flight that already occurred earlier in the month with the regional CRJ700.

The Boeing 737-800 also services flights to Austin, Texas, at 1,504 miles, but only 10 of the pronounced 281 flights to the city in April utilize this aircraft. Additional routes include Puerto Vallarta in Mexico, Nashville in Tennessee, and Atlanta in Georgia, where flight frequencies show variability in aircraft utilization based on route demand.

United Airlines' third-longest international route using the 737-800 is to Toronto, Canada, at 2,260 miles. On this cross-border journey, United meets competition from other airlines, including twice-daily fights from Air Canada.

San Francisco maintains a 2,400-mile connection to Raleigh-Durham, North Carolina, and this month sees a small fraction of these being served by the 737-800. In contrast, Baltimore sees the longest of United Airlines' routes from San Francisco using the 737-800, at 2,457 miles, making approximately 55 flights in both directions, albeit with limited availability from the 737-800 on outbound and inbound legs.

"These flights typically last around five hours and 15 minutes, with the second of the two daily eastbound departures operating overnight."