Flights for UA2121 These are not all the flights that UA2121 has taken, just some of them that have flown in or out of SFO

UAL2121 (SFO-LAX)
This United Airlines flight traveled from San Francisco International Airport to Los Angeles International Airport, on March 24, 2015. Passengers were flying aboard a Boeing 747-400. See all the flights for UA2121.
UAL2121 (SFO-LAX)
This United Airlines flight traveled from San Francisco International Airport to Los Angeles International Airport, on October 31, 2014. Passengers were flying aboard a Boeing 777-200. See all the flights for UA2121.
UAL2121 (SFO-XMN)
This United Airlines flight traveled from San Francisco International Airport to Xiamen Airport, on September 04, 2014. Passengers were flying aboard a Boeing 747-400. See all the flights for UA2121.

All these flight data are available as openly licensed data on the sfomuseum-data GitHub account. If you'd like to read more about our efforts to archive flight data at SFO Museum have a look a the Mills Field weblog posts tagged "flightdata".