Researchers have unveiled a futuristic, low-cost fuel-efficient engine that is twice as powerful as ordinary turbofans and could radically change the way the jet set flies
Why a Mach 5 passenger plane is a crazy idea that might just work
Boeing and engine manufacturers Rolls-Royce and Rolls-Royce, together with US battery producer Saft have unveiled a vision of the future air travel industry, one that is likely to delight jet setters, troublemakers and low-cost airlines.
Dotting the diagrams on a page of their website they demonstrate a unique hybrid jet engine for commercial aeroplanes, one capable of burning a much lower proportion of fossil fuels than ordinary ones and providing a “billions times quieter” – essentially safer – travel experience.
The secret is that the engine has a powerful single cylinder, capable of powering the wing of the aircraft, while a much more fuel-efficient second cylinder powers the bottom floor.
This can easily be folded up and stored in the cabin, making it quieter and safer than conventional turbofans and making long-haul flights possible on smaller planes.
By contrast, standard planes have a single combustion unit that generates a large number of engines and turbofans, essentially cramming everything into one space. Each turbofan can generate more than 1,200-1,800 horsepower (between 20 and 70hp) but this figure is exceeded by conventional engines, which run at a much higher speed and are capable of generating a total of more than 6,000hp.
A result of all that power is also the noise created by air and turbo-charged engine.
The Boeing and Saft team proposed that in the future a single mega-engine aircraft could have as many as seven of the fantastically energy-efficient engines, with the low-level second-stage blades serving as the equaliser between the two engines. These new engines could fly at Mach 5, a fifth of the speed of sound, while also producing up to 90% less pollution and emitting 60% less noise.
Together with the advent of new lithium-ion battery technology, this approach could be radically improved by transforming traditional aircraft from turbofans to electric motors that run to either sides of the engines as each stage of the plane is underway.
“It will be a radical leap forward for air travel,” said Anders Thomson-Sørensen, head of business development at Boeing.
Newer aircraft will not have to be retrofitted to use the new engines, he added. “They will just have to be upgraded and fly with the new hybrid engine.”
Airlines are likely to be happy with the new engines, as a pitch for a jet pool will be made. “More customers flying in cheaper versions of the aircraft will lead to more efficient flight times and lower costs,” said Craig Connell, research manager at avionics firm Rockwell Collins.
The idea of competing airlines piloting their own planes with different engines has been, until now, seen as a rather foolhardy move.
The life cycle cost of its components would be higher, for example as aircraft passengers complained about the noise pollution and the higher overall cost of flying. These added costs would offset savings through the quieter engines and reduced pollution.
Modern engines are fast becoming a colossal infrastructure, but it could be a different story in future, said Gavin Groves, chief commercial officer at Rolls-Royce.
“If we can start looking at the time that we put the [mega-engine] on versus [chipping] away at the existing engine, you could bring down the whole life cycle of the engine,” he said.
The designs are only speculative, though, and are still a few years from even making an appearance.
However, experts are pushing to find solutions by working on advanced materials and techniques to advance the age of composites in aeroplanes and related structures. Boeing believes that conventional oil-based technology is on its way out.
“The era of turbofans is not dead yet but it is maturing,” said Henry Schwake, president of Boeing’s advanced engineering group.
“The 747-8 is now a true hybrid, offering a growth in capacity and the promise of a quieter and more eco-friendly flying experience,” he added.
