Travel Day: First Stop London

Just boarded this United Airlines 777-200(ER?) for my flight to LHR. I
wish I knew the registration. Help anyone? Flight 918 IAD-LHR. Paris
on Saturday. Let the whirlwind begin.

UPDATE: On the ground safe and sound once again. Thanks for all the help identifying this 777. United's terminal at Dulles is notoriously bad for seeing registrations, and I was able to get a good look at Heathrow. The aircraft in question is N796UA, a 777-222ER (112/26931) delivered to UAL in January 1998.

UAL918 Flight Plan - KIAD - EGLL:

SWANN V268 BROSS J42 RBV ACK WHALE N23E LOMPI N21C JAROM NATW SOMAX NATW KENUK UL739 GAPLI UR8 GIBSO OCK2E