Story ID: 469
Rolls-Royce Begins Building Giant Fans 
By: David Donald
Caption: Part of the drive to increase engine efficiency and reduce emissions, the Rolls-Royce UltraFan employs advanced composite fan blades.
Word Count: 234
UK aero-engine manufacturer Rolls-Royce (Chalet AC05, Booth N23) has said that it has started building the fan blades for its UltraFan demonstrator engine at its Bristol technology hub. At 140 inches (3.56 meters) diameter, the fan set will be the largest ever made.
The blades are created through the build-up of hundreds of layers of carbon-fiber materials pre-filled with resin, which are then heat- and pressure-treated. A thin titanium leading edge is fitted for protection against foreign object damage, erosion, and bird strikes. This technology has already been tested on the Advanced Low-Pressure System development engine—a partnership with Clean Sky, Innovate UK, BEIS, ATI, ITP Aero, and GKN—and inflight on Rolls-Royce's Boeing 747 flying testbed.
UltraFan is a project to demonstrate a range of technologies and new materials that can significantly improve efficiency by reducing fuel-burn of jetliner engines, which also has a beneficial effect on emissions. The new composite fan blades and fan case would reduce weight on a typical twin-engined airliner by 1,540 pounds (700 kg), and the project aims to deliver a 25 percent reduction in fuel-burn compared to first-generation Rolls-Royce Trent engines.
The UltraFan program is ultimately intended to produce a family of scalable engines with thrust ratings between 25,000 and 100,000 pounds. Ground tests of the technology demonstrator are due to begin in 2021, and Rolls-Royce hopes to have production engines available towards the end of the 2020s.