Narrative:

First officer (first officer) was the pilot flying and the captain was the pilot monitoring. On initial engine start the left engine driven generator failed to come on line; cycled the generator control switch and the left generator took the load and powered the left bus tie. Takeoff; departure and climb to cruise were uneventful. Approximately 1.5 hours into the flight; the autopilot and auto throttles disconnected the captain's displays blanked and numerous EICAS message came up indicating loss of left aircraft bus tie and left generator. The first officer took over the controls and stabilized the aircraft and the captain initiated the aircraft bus off-left in the QRH. Attempted one generator reset per the checklist; the generator failed to assume the load. Started the APU; cycled the bus tie switch and powered the left bus. Contacted ATC and requested a divert to ZZZ. ZZZ was chosen since ZZZ and ZZZ1 etas were within 2 minutes of each other; maintenance is readily available at both; but passenger issues could be better handled there. Also since we were on the southernmost track there would be less chance of a traffic conflict if we returned to ZZZ versus ZZZ1. The aircraft is not equipped with satcom; therefore consultation with dispatch was not immediately available. Initiated the diversion procedures. Center cleared conflicting aircraft from our flight level and approved the return to ZZZ. Initiated a left 180 degree turn direct to zzzzz intersection; once established setup a 2 mile right offset. Requested a lower altitude to increase fuel burn and reduce the aircraft landing weight; however due to conflicting opposite direction traffic we were unable to descend. Initiated a HF phone patch through with dispatch and maintenance control. Related to problem and our intentions; and requested ZZZ be alerted. Routing was via the zzzzz intersection to [a] runway. Remainder of flight proceeded normally to an overweight but normal landing. The aircraft was approximately 14;000 pounds over weight on touchdown. Logbook entries were made for the generator failure and overweight landing.

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Original NASA ASRS Text

Title: B757 Captain reported a generator failure led to a return to the departure airport.

Narrative: First Officer (FO) was the Pilot Flying and the Captain was the Pilot Monitoring. On initial engine start the left engine driven generator failed to come on line; cycled the Generator Control switch and the left generator took the load and powered the left bus tie. Takeoff; departure and climb to cruise were uneventful. Approximately 1.5 hours into the flight; the autopilot and auto throttles disconnected the Captain's displays blanked and numerous EICAS message came up indicating loss of left Aircraft Bus Tie and Left Generator. The FO took over the controls and stabilized the aircraft and the Captain initiated the Aircraft BUS OFF-L in the QRH. Attempted one generator reset per the checklist; the generator failed to assume the load. Started the APU; cycled the BUS TIE switch and powered the left bus. Contacted ATC and requested a divert to ZZZ. ZZZ was chosen since ZZZ and ZZZ1 ETAs were within 2 minutes of each other; maintenance is readily available at both; but passenger issues could be better handled there. Also since we were on the southernmost track there would be less chance of a traffic conflict if we returned to ZZZ versus ZZZ1. The aircraft is not equipped with SATCOM; therefore consultation with dispatch was not immediately available. Initiated the Diversion procedures. Center cleared conflicting aircraft from our flight level and approved the return to ZZZ. Initiated a left 180 degree turn direct to ZZZZZ Intersection; once established setup a 2 mile right offset. Requested a lower altitude to increase fuel burn and reduce the aircraft landing weight; however due to conflicting opposite direction traffic we were unable to descend. Initiated a HF phone patch through with Dispatch and Maintenance Control. Related to problem and our intentions; and requested ZZZ be alerted. Routing was via the ZZZZZ Intersection to [a] runway. Remainder of flight proceeded normally to an overweight but normal landing. The aircraft was approximately 14;000 pounds over weight on touchdown. Logbook entries were made for the generator failure and overweight landing.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.