SYDNEY – Passengers on Qantas Flight QF63 witnessed a curious sight last week when their plane flew to South Africa with not four, but five engines. Business Insider Australia reports that a Boeing 747 Qantas flight from Sydney to Johannesburg on Wednesday was carrying unusually heavy baggage – six tonnes to be exact – in the form of a fifth engine.The rare move was meant to carry the replacement Rolls Royce engine to a plane in Johannesburg to get it back in the air sooner. With the 747 designed to carry additional cargo on its left wing, Qantas explained it merely had to fit the aircraft with anchor points, attach a supporting strut, and hoist the engine up using a winching mechanism to secure it safely. The fifth engine was not powered for the flight, but did add weight and drag, which meant the plane had to fly slower and make a refueling stop in Perth before the 11-hour flight to South Africa. After flight QF63 landed, the engine was removed and fitted onto the other plane, which made the return trip back to Sydney, according to 9News. The replaced engine will be shipped back by boat.