Automotive

Rolls-Royce claims world's most powerful aerospace gearbox record

Rolls-Royce claims world's mos...
Rolls-Royce is inching closer to having a production-ready UltraFan engine
Rolls-Royce is inching closer to having a production-ready UltraFan engine
View 3 Images
The Rolls-Royce Power Gearbox being put to the test in Germany 
1/3
The Rolls-Royce Power Gearbox being put to the test in Germany 
The Rolls-Royce Power Gearbox being put to the test in Germany 
2/3
The Rolls-Royce Power Gearbox being put to the test in Germany 
Rolls-Royce is inching closer to having a production-ready UltraFan engine
3/3
Rolls-Royce is inching closer to having a production-ready UltraFan engine

A successful test has seen Rolls-Royce claim the world record for the world's most powerful aerospace gearbox with its Power Gearbox. The unit is capable of handling the power from around 400 regular family cars running at full throttle and will form a key part of Rolls-Royce's next-generation UltraFan engine, allowing it to operate efficiently through the full range of thrusts.

The Power Gearbox was first tested last year, but power wasn't the focus. Engineers used the Rolls-Royce Attitude Rig to simulate climbing, descending and banking, and find out how each maneuver affected the oil system.

The latest tests were more rigorous. Paul Stein, CTO at Rolls-Royce, used a speech at the International Society for Air Breathing Engines (ISABE) to announce 70,000 hp (52,199 kW) had successfully been run through the 'box at the company's German facility. It will eventually channel 100,000 hp (74,570 kW), at which point Rolls-Royce says each pair of teeth on the gearbox will be transmitting more power than the entire F1 grid.

The Rolls-Royce Power Gearbox being put to the test in Germany 
The Rolls-Royce Power Gearbox being put to the test in Germany 

Why? Well, fitting bigger fans to aircraft engines delivers more power, but it also necessitates the fitment of bigger turbines – and there comes a point where turbines would need to be prohibitively large for any meaningful power gain. UltraFan is designed to avoid this problem, using the (planetary) Power Gearbox to keep the turbine and fans spinning at the ideal speed throughout a flight for more power and better efficiency.

"Setting this record is a great achievement for the team and I'm proud we've managed to get there so quickly," says Paul Stein, CTO at Rolls-Royce. "Our Power Gearbox technology is central to the success of the next generation of Rolls-Royce jet engines and I'm pleased to see us pushing back engineering boundaries with this work."

When it arrives in 2025, the UltraFan engine is expected to be around 25 percent more efficient than current-generation Rolls-Royce Trent engines.

Source: Rolls-Royce Aerospace

3 comments
MarylandUSA
Another British firm, Sturmey-Archer, graced tens of millions of 3-speed and 5-speed bicycles with its planetary gearbox. Must be a British strength. More on geared turbofans can be found at https://en.wikipedia.org/wiki/Geared_turbofan I wonder what became of the large gearless turbofan that was being developed by Rolls competitor General Electric? GE-SNECMA has introduced the LEAP engine, which is gearless. But it's not the giant gearless high-bypass design they were toying with a decade or two ago.
Martin Hone
No mention of what was required in order to achieve this. And a gearbox cannot be considered 'powerful' if it doesn't make power. It accepts power in the form of torque in order to do work, whether it is changing direction, reducing revs or torque multiplication. R-R has been good at this ever since the Merlin V12
MD
This development is one which is only logical... (a known problem ever since the first geared propeller drive was invented), simple to see (intuit) the disparity in efficient RPM due to the difference in diameters (*pi). "props" to the gearbox engineers for figuring the material combinations to work effectively, lets see how it holds up in 10000 hours of real ops. (the analogy to an F1 "grid per tooth" are only for the masses, give them more bread and circuses) This is merely a stopgap. The Ideal aircraft will be powered by the absolutely most efficient gas generator / power converter (efficiency increases with size, so as big as necessary), combined with a totally "decoupled" highly efficient e-fan. (batteries may eventually be good enough for minimum legal flight reserves allowing a single gen-set in large continental Transports). In another generation or 2 we will see the "jet engine" relegated to being an electric gen-set, and the FANS being electrically driven allowing the best of both worlds. But while-ever gears (and 85% efficiency) are more optimal than generator+motors (and 90% efficiency) engineers will use the "lowest cost" (in terms of engineering optimisation) solution.