Rolls-Royce Tests the Ultimate Turbofan Engine at Full Power, Nothing Gives Way

Take Rolls-Royce for instance, perhaps the largest maker of aircraft engines in the world. The British company had over the years several powerplant families in its portfolio. The current lineup comprises several variants of something called the Trent, and the Pearl line.

This breed was born in the 1990s, and presently offers those involved in aircraft-making nine versions to choose from. Yet, despite being just 33 years old, the engine uses a three-spool architecture Roll-Royce introduced more than half a century ago.

That's one of the reasons why the upcoming UltraFan unit is such an important piece of tech for the engine maker. Dubbed "the ultimate turbofan" engine, it is the first new architecture one the company has introduced in 54 years.

The powerplant was first unveiled as a concept back in 2014, but it took Rolls-Royce almost a decade to have the thing ready for testing. It was only early this year that testing for the thing started at the engine maker's facility in Derby, UK.

The engine is for now just a technology demonstrator, but at the rate at which things are now moving it probably won't be long until we see it deployed on an aircraft. Following the initial tests at the beginning of 2023, Rolls-Royce gradually increased the power of the unit until earlier this week it was ready to announce the completion of the first UltraFan test to maximum power.

It's unclear exactly what that means as the engine was built to be scalable. It can develop anywhere between 25,000 and 110,000 pounds of thrust, not in small part thanks to the fan that is a staggering 140 inches in diameter (3.55 meters).

The blades of the piece are made of carbon composite titanium and their size makes them the largest of their kind in the world.

The specially developed hardware that should help the powerplant run as advertised includes a gearbox rated at 50 MW, or about as much as 500 family cars would be capable of generating. The system even went to 64 MW during testing, an aerospace record, and that translates into roughly 87,000 horsepower!

The geared design of the engine not only makes it different than anything Rolls-Royce has made before, but it also makes for something no other player in the industry has been capable of doing at this scale before.

The aero engine is considered the largest of its kind in the world, and it has been specifically developed to power narrowbody and widebody aircraft arriving to the aviation scene in the 2030s.

Compared to the first-generation Trent family engine, the powerplant should deliver 25 percent more fuel efficiency. That's a ten percent improvement over the current Trent XWB, the present-day most efficient aero engine of its size. On top of that, the UltraFan should release 40 percent less NOx and generate 35 percent less noise than the Trent.

That is possible thanks in part to something called the Advance3 core architecture and the ALECSys lean burn combustion system that help increase burn efficiency and cut down on emissions.

More importantly, the powerplant can run completely on Sustainable Aviation Fuel (SAF), which it actually did during the tests whose completion was announced by the Brits.

As per the details of this most recent test, the UltraFan "has performed in line with our expectations." Rolls' engineers will now gather all the data to analyze and further refine the engine.

Technically speaking the UltraFan engine should be ready for operation sometime by the middle of the current decade, but realistically speaking the late 2020s is probably a safer bet. Until it gets here, though, some of the technologies developed for it might make it into the Trent family of engines. The company does not say exactly what technologies those would be.

Like most other companies in the transportation business, Rolls-Royce too has set a target for Net Zero flying. In its case it plans to achieve that by the middle of the century, and the UltraFan is one of the pillars on which that target was built.

In fact, it's the most important such pillar, as it is supposed to account for no less than 80 percent of the goal, when running completely on SAF.

It's not clear at this point when we'll get to see the first actual test flight of the engine. It will probably be soon, marking an important moment in the company's history. And probably in our lives too, as it's not everyday when we get to see a brand new aircraft engine being born.