The Rolls-Royce Trent 7000 engine for the Airbus A330neo is an all new power plant, and will by the 7th variant in the Trent series. We spoke with Richard Goodhead, Vice President of Customer Marketing, to obtain additional details about the new engine.
The Trent 7000 will offer the same thrust as the Trent 700, the leading engine on the A330ceo models, but will be a totally new design. Based largely on architecture of the Trent 1000-TEN used on the Boeing 787, with additional technology from the Trent XWB used on the A350, the Trent 7000 will offer an 11% improvement in fuel burn per seat on the new aircraft. Combined with aerodynamic and other improvements to the aircraft, the A330-neo will achieve a 12% reduction in trip fuel and a 14% reduction in fuel per seat.
There are several technologies and features that provide the performance boost for the Trent 7000. These include a larger fan diameter, 112 inches versus 97 inches. This helps double the bypass ratio of the new engine from 5 to 10. At the same time, the overall pressure ratio of the engine increases from 36 to 50, providing improved thermal efficiency. This efficiency does come with higher internal temperatures, about +200 degrees Kelvin, and the high pressure turbine blades have been thermally coated to prevent excessive wear. These temperatures are not hot enough to require more expensive ceramic matrix composites, which will be introduced with the next generation of Rolls-Royce engines in the 2020 time frame.
With the Trent 700 now 20 years old, technologies have changed dramatically in some areas and evolved more slowly in others. Major features of this engine include state of the art Full Authority Digital Engine Controls (FADEC) and Engine Health Monitoring (EHM) systems that reflect today’s more advanced capabilities in software. Rolls-Royce is also utilizing its ENABLES technology to more easily maintain engine accessories and to simplify the plumbing and wiring on the outside of the engine.
The fan hub for the Trent 7000 is smaller than the hub for the Trent 700, enabling additional improvement in the bypass ratio without having to further increase fan size. The smaller hub saves more than an inch in fan diameter, and associated additional weight. Of course, with a fan that is 15% larger, the low pressure turbine requires two more stages to move the additional size. That combination will make the Trent 7000 about 3,500 pounds heavier than the Trent 7000. Even with that additional weight, and additional drag from the larger fan, the Trent 7000 delivers 11% better fuel burn on wing than the Trent 700.
The IP drive, while not needed to generate electrical power since this will use bleed air, enables the high pressure compressor to maintain stability at low power settings, dramatically improving low speed fuel consumption. This is especially important for short-haul operations.
The core compressor uses Trent XWB technology to achieve the overall pressure ratio of 50:1 for the engine. The engine also features active turbine clearance control to provide the optimal level of cooling air for different phases of flight.
A summary of the engine characteristics for the existing A330ceo and A330neo follows in the table below:
Aircraft engines have always driven aircraft technology, and in this era of re-engined A320s, 737s, 747s, 777s and now A330s, these performance improvements have provided additional life to aircraft programs. The A330neo, using the Trent 7000, appears well positioned to deliver additional value to airline customers and extend the life of the A330 program for another decade or more.