Bearings for open-rotor aero-engines

Helen Knight reports

A new aircraft engine design that could cut greenhouse gas emissions from air travel is a step closer to reality, thanks to the development of advanced bearings.

The new engine design, known as Open Rotor, is being developed as part of the EU’s huge Clean Sky research programme, in a project called Sustainable and Green Engine (SAGE) demonstrator SAGE2.

Open-rotor aircraft engines generate most of their thrust from two counter-rotating propellers, rather than the ducted fan that drives conventional turbofan engines.

This means the engine diameter can be larger, improving its efficiency, without creating the need for an excessively big and heavy engine nacelle.

The concept was first investigated in the 1980s, following the oil crisis where the price of fuel sky-rocketed. But as the oil price dropped again, interest in the idea waned. Now the concept is being revived, in a bid to reduce fuel consumption and carbon dioxide emissions from air travel.