A British Airways Boeing 747-400, registration G-CIVD performing flight BA-177 from London Heathrow, EN (UK) to New York JFK, NY (USA), was en route at FL360 over the Atlantic Ocean about 800nm west of Shannon (Ireland) when the crew decided to return to London due to electrical problems. The aircraft landed safely at Heathrow Airport about 5:15 hours after departure.
The flight was cancelled.
A passenger reported the in-flight entertainment system failed shortly after departure soon followed by the lighting in cabin and lavatories. Some more time later the galleys lost power and the only lights remaining were the passenger overhead signs. Cabin crew detected an unusual odour, flight crew performed an inspection of the cabin to determine the source of the odour. The aircraft subsequently turned around, about 15 minutes after turning around the captain announced they were returning to Heathrow due to issues with one of the electrical systems. After landing the passengers were accommodated near the airport, they were rebooked onto flights the next day.