British Airways B744 near Lisbon on Jul 19th 2014, electrical problems

A British Airways Boeing 747-400, registration G-CIVX performing flight BA-247 from London Heathrow,EN (UK) to Sao Paulo Guarulhos,SP (Brazil), was enroute at FL310 about 120nm northwest of Lisbon (Portugal) when the crew decided to divert to Lisbon reporting electrical problems. The aircraft entered a hold at 3000 feet (utilizing extended 5 minute legs) near Lisbon to dump fuel, the crew requested emergency services on standby purely as a precaution, and the aircraft landed safely on Lisbon's runway 03 about one hour after leaving FL310.

A replacement Boeing 747-400 registration G-BYGG was dispatched to Lisbon, resumed the flight as BA-9609 and reached Sao Paulo with a delay of 20 hours.

The occurrence aircraft positioned back to London on Jul 21st departing Lisbon about 33 hours after landing and resumed service.

A passenger reported they had been diverted due to electrical issues. They were accomodated over night in Lisbon and boarded the replacement aircraft the following day.