As aircraft and aircraft engine manufacturers strive for greater efficiencies and better performance, one strategy has been to increase bypass ratios for turbofan powerplants. Achieved by increasing the overall diameter of the engine, Rolls-Royce’s UltraFan engine is set to be 140 inches or 3.56 meters- just a little wider than the 3.48-meter-wide Airbus A220 fuselage.
It was at the end of March that Rolls-Royce confirmed it had begun construction on its demonstrator engine for the upcoming ‘UltraFan‘ family. This is set to be the world’s largest commercial jet engine, with the fan itself measuring 140 inches (3.56 m) wide.
In fact, this will beat out General Electric’s iconic GE90-115B engine by 12 inches, as the GE offering measures 128 inches in diameter. GE’s newer offering that’s set to power the Boeing 777X, the GE9X, will measure 134 inches in diameter, six inches narrower than the UltraFan.
But isn’t the GE9X wider than a 737 fuselage?
The huge engines of the Boeing 777X have seen plenty of talk that they could fit a Boeing 737 fuselage inside them. This is something WIRED titled one of its articles.
The WIRED article also mentions that a GE publicist noted if professional basketball player “Kobe sat on Shaq’s shoulders, the two of them could easily walk through it.” A strange comparison to make – but perhaps the point comes across more clearly for aviation fans who also watch professional basketball.
So, if you’re one of the people that has heard this before, you might be wondering why we’re comparing the Rolls-Royce UltraFan with an Airbus A220 – isn’t this Airbus type narrower than the 737? After all, in economy class, an A220 is typically five-abreast seating while the 737 is six seats across. What’s going on here?
Well, we can only assume that the GE9X-Boeing 737 fuselage comparison takes into account the GE9X’s engine cowling as well, which will certainly broaden the engine’s diameter. It’s clear, however, that comparing published fan diameters, the UltraFan wins out. Thus, we can assume that the UltraFan will be even wider once it is placed within its cowling.
With the construction of the demonstrator UltraFan underway, Rolls-Royce is drawing support from both the British and German governments. Parts are under construction in both Bristol (UK) and Dahlewitz (Germany). These will be delivered to its DemoWorks facility in Derby (UK).
“This is an exciting moment for all of us at Rolls-Royce. (…) It is arriving at a time when the world is seeking ever more sustainable ways to travel in a post-COVID-19 world, and it makes me and all our team very proud to know we are part of the solution.” -Chris Cholerton, President, Rolls-Royce
At the end of the day, engine size may be quite impressive. But for those in the business, it’s not at all what really matters: For airlines, what will matter most is efficiency and reliability. At the same time, technicians will care about dependability and ease of serviceability.
Are you excited about the UltraFan and its development? Let us know in the comments.