Three months ago a South African Airways Airbus A330 from Accra, Ghana to Johannesburg reported both engines surging while over Botswana. The aircraft, with 209 people on board, continued the final 50 minutes to Johannesburg even as surges continued on final approach.
Reportedly the airline had just changed fuel suppliers in Accra. And after water had been drained from the fuel system, the aircraft was signed off for a ferry flight back to South Africa – with no passengers – but a full complement of passengers was loaded anyway.