Imagining a plane with five engines certainly presents an intriguing design concept, blending the familiar with the extraordinary.
Well, that’s exactly what some lucky passengers and observers witnessed when Qantas, the Australian flag carrier, flew a Boeing 747 with an extra engine on its wing across the world.
The unusual sight was captured by aviation enthusiasts and shared on social media, sparking curiosity and admiration.
The extra engine was needed to replace a broken one on another Qantas 747 stranded in South Africa.
Instead of shipping the spare engine by cargo, Qantas decided to use a special technique that allows the 747 to carry an extra engine on its wing.
The technique is called “ferrying” and it involves mounting the extra engine on a special pylon on the innermost strut of the left wing.
The extra engine is not connected to the aircraft’s systems and does not provide any thrust.
It is simply a dead weight that is carried along for the ride.
“It’s very rare but we can do it. It’s an engineering feat that has been done by Qantas for many years.” said a Qantas spokesman in 2016, when the airline performed its latest ferrying operation between Sydney and Johannesburg.
Qantas has used this technique at least three times in its history: in 1989, 2002 and 2016.
The first time was when a Qantas 747 flew from London to Sydney with an extra engine, setting a world record for the longest non-stop flight by a commercial aircraft at the time. The second time was when a Qantas 747 flew from Los Angeles to Auckland with an extra engine, after another Qantas 747 suffered an engine failure over the Pacific Ocean.
The ferrying technique requires special approval from aviation authorities and involves careful calculations of weight, balance and aerodynamics. The extra engine adds about 500kg of drag and increases fuel consumption by about 3%. It also creates more noise and vibration for the passengers and crew.
“It was a very interesting sight to see an aircraft with five engines. It looked like a rocket.” said a Qantas pilot who flew the 1989 ferrying flight.
The Boeing 747 is one of the few commercial aircraft that can carry an extra engine on its wing. Other aircraft, such as the Airbus A380 or the Boeing 777, have to transport spare engines by cargo or use smaller aircraft to ferry them.
The ferrying technique is not only a cost-effective way of delivering spare engines, but also a testament to the engineering marvel and versatility of the Boeing 747, which has been in service for more than 50 years.
Relevant articles:
–Qantas Once Flew A Boeing 747 With 5 Engines (simpleflying.com)
– The Boeing 747 Could Fly With 5 Engines (simpleflying.com)
– Which Aircraft Can Carry An Extra Engine On Their Wings? (simpleflying.com)
– How Qantas Ferried an Engine on the Wing of a 747 | Flightradar24 Blog