Electric airliners, 4D-printed ceramics and Pearl 15: most-read stories of 2018, July – Sept

Change is the most exciting aspect of engineering, the constant innovation that transforms how we live and work.

With another year coming towards its end, we've looked back at what happened by taking stock of our most-read stories from each month.

Read part one here.

Read part two here.

July: Electric airliners – preparing for take-off, or flights of fancy?

The aviation industry burns 5m barrels of oil every day – hardly a sustainable operation, and that number is set to rise as air travel increases in the coming decades.

Companies are desperate for an alternative, if not for environmental reasons then to save money on expensive fuel. But with several challenges in the way, will electric flight ever be a realistic option for widespread global travel?

August: World’s first 4D-printed ceramics unfold over time

4D printing, is, according to research announcements, just like 3D printing but with the additional dimension of time – printed objects can transform over time in response to stimuli such as heat or light.

Despite the jargon-y, buzzword name, the process could be of real use in engineering sectors such as aerospace and electronics. 4D-printed ceramics from the City University of Hong Kong could be useful for antennas and heat shields, researchers said.

September: Inside Pearl 15, the small but mighty new Rolls-Royce engine for business jets

While electric flight remains out of reach, manufacturers are exploring other ways of improving fuel efficiency. Rolls-Royce's Pearl 15 is one such effort, designed for Bombardier's Global 5500 and Global 6500 aircraft. The engine's twin-spool set-up means the high pressure compressor rotates independently of the low pressure compressor and turbine blades, helping improve fuel efficiency and range.