Today’s QF63 from Sydney to Johannesburg took off with an extra passenger on board – a six tonne Rolls Royce engine.

With its four powerful engines and distinctive upper deck, the Boeing 747 is instantly recognisable wherever it flies.

What you might not know is that the 747 has the ability to carry a fifth engine, fitted between the body of the aircraft and the inner-most engine on the port (left) side of the aircraft.

The extra engine isn’t powered up for the flight – we’re essentially ferrying across a very large spare part from our engineering HQ in Sydney so it can be fitted to one of our other Boeing 747s in Johannesburg.

We’re undertaking this rare task to get our customers and our aircraft on their way as quickly as possible – rather than shipping the engine across by boat or chartering a freighter aircraft.

So how exactly is a 747 able to carry a spare engine?

The wing of the aircraft is fitted with anchor points, which allows a supporting strut to be attached under the wing.

The strut is fitted with a winching mechanism so the engine can be hoisted up and secured safely for its journey.

The fifth engine adds extra weight and drag to the aircraft, meaning today’s flight had to make a quick refuelling stop in Perth.

Additional drag is caused by air travelling around the spare engine during flight and, to counterbalance this, our pilots are trained to use the flight controls to ensure the aircraft flies straight, level and safely.

Once QF63 has landed in Johannesburg – it’s simply a matter of removing the fifth engine and then putting it onto the aircraft that will operate QF 64 to Sydney.

Our engineers are very skilled at doing the job, given that the 747 has been an integral part of the Qantas fleet since the 1970s.

We first pioneered the carriage of a fifth engine with our Boeing 707s back at the dawn of the jet age to save shipping costs. The last time we carried an engine like this was back in 2011.

And what about the spare engine that we removed in Johannesburg? It will be sent home by boat – a much longer journey than by air as an extra passenger under the wing to Sydney.

At our maintenance base in Sydney we hold millions of spare parts ranging from the smallest screws, seat cushions, to 747 engines.

Keep checking on our blog – we’ll take you inside the ultimate tool shed very soon!

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