The Rolls-Royce Trent is a family of high-bypass turbofans produced by Rolls-Royce. It continues the three spool architecture of the 1972 RB211 with a maximum thrust ranging from . Launched as the RB-211-524L in June 1988, the prototype first ran in August 1990. Its first variant is the Trent 700 introduced on the Airbus A330 in March 1995, then the Trent 800 for the Boeing 777 (1996), the Trent 500 for the A340 (2002), the Trent 900 for the A380 (2007), the Trent 1000 for the Boeing 787 (2011), the Trent XWB for the A350 (2015), and the Trent 7000 for the A330neo (2018). It also has marine and industrial variants such as the RR MT30.
Development
Despite the success of the RB211, Rolls-Royce's share of the large civil turbofan market was only 8% when it was privatised in April 1987, the market being dominated by General Electric and Pratt & Whitney. In June 1987, Rolls-Royce was studying whether to launch a thrust variant of the RB211, to be called the RB211-700, for the Airbus A330 twin-jet, the long-range Boeing 767 and the MD-11, derived from the 747-400's -524D4D, with growth potential to . By June 1988, Rolls-Royce was investing over $540 million to develop the uprated RB-211-524L with a new fan (up from ) for the -524G/H and a fourth LP turbine stage up from three, targeting .
At the September 1988 Farnborough Airshow, the -524L development was confirmed, estimated at £300 million, to power the MD-11 and A330 as a full-scale model was unveiled by Frank Whittle. In June 1989, the RB211-524L Trent was confirmed for the A330, rated at . Rated at for the MD-11, the Trent made its first run on 27 August 1990 in Derby. By September 1992, the Trent 600 for the MD-11 was abandoned and prototypes were rebuilt as Trent 700 engines for the A330 with a fan.
The UK government granted Rolls-Royce £450 million of repayable launch investment, repaid with interest, to develop the RB.211 engine and the Trent family up to the Trent 900. Rolls-Royce obtained £200 million for the Trent 8104, 500 and 600 variants in 1997, and £250 million for the Trent 600 and 900 variants in 2001.
New proposed planes required higher thrust and customers wanted the Boeing 777 and Airbus A330 twinjets to fly Extended-range Twin-engine Operations at introduction. Rolls-Royce decided to offer an engine for every large civil airliner, based on a common core to lower development costs, and the three-shaft design provided flexibility, allowing each spool to be individually scaled. In keeping with Rolls-Royce's tradition of naming its jet engines after rivers, the engine family is named after the River Trent in the Midlands of England, a name previously used for the RB.50, Rolls-Royce's first working turboprop engine; and the 1960s RB.203, a bypass turbofan and the first three-spool engine, designed to replace the Spey but never introduced.
In 2019, Rolls-Royce delivered 510 Trent engines.
Design
Like its RB211 predecessor, the Trent uses a concentric three-spool design rather than a two-spool configuration. The Trent family keeps a similar layout, but each spool can be individually scaled and can rotate more closely to its optimal speed. The core noise levels and exhaust emissions are lower than those of the RB211.
Hollow titanium fan blades with an internal Warren-girder structure achieve strength, stiffness and damage tolerance at low weight. To allow the blades of the HP turbine to operate in temperatures above their melting point, cooling air is bled from the compressor through laser-drilled holes in the hollow turbine blades, each made from a single crystal of a nickel alloy and covered by thermal barrier coatings. Each turbine blade removes up to from the gas stream.
In April 1998, the RB211-524HT was introduced for the 747-400 with the Trent 700 core, replacing the previous RB211-524G/H with 2% better TSFC, up to a 40% lower NOx emissions and a 50 °C cooler turbine. The Trent 800 LP spool rotates at 3300 rpm, its diameter fan tip travels at m/s. The Trent 900's fan keeps a low mean jet velocity at take-off to lower the Airbus A380's noise.
Variants
First Trent 600 At the McDonnell Douglas MD-11 programme launch at the end of 1986, the airframe was only offered with GE CF6-80C2 or PW4000 engines, however Rolls-Royce was preparing to propose the 747-400's RB211-524D4D rated at . By June 1988, Rolls-Royce was investing over $540 million to develop the uprated RB-211-524L with a new fan (up from ) for the -524G/H and a fourth LP turbine stage up from three, targeting . Rated at , the Trent made its first run on 27 August 1990 in Derby. By July 1991, the MD-11 Trent was abandoned after the demise of Air Europe, its only customer. By February 1992, there were four Trent 600 engines with a fan. By September 1992, three had been rebuilt as Trent 700 engines for the A330 with a fan.
Trent 700
Rolls-Royce was studying a RB211 development for the Airbus A330 at its launch in June 1987. The Trent 700 was first selected by Cathay Pacific in April 1989, first ran in summer 1992, was certified in January 1994 and put into service in March 1995. Keeping the characteristic three-shaft architecture of the RB211, it is the first variant of the Trent family. With its fan for a 5:1 bypass ratio, it produces of thrust and reaches an overall pressure ratio of 36:1. It competes with the GE CF6-80E1 and the PW4000 to power the A330.
Trent 800
The Trent 800 is one of the engine options for the early Boeing 777 variants. Launched in September 1991, it first ran in September 1993, was granted EASA certification on 27 January 1995, and entered service in 1996. It reached a 40% market share, ahead of the competing PW4000 and GE90, and the last Trent 800-powered 777 was delivered in 2010. The Trent 800 has the Trent family three shaft architecture, with a fan. With a 6.4:1 bypass ratio and an overall pressure ratio reaching 40.7:1, it generates up to of thrust.
Trent 8100
In the early Trent 800 studies in 1990, Rolls-Royce forecast a growth potential from with a new HP core. By March 1997, Boeing studied 777-200X/300X growth derivatives for a September 2000 introduction: GE was proposing a GE90-102B, while P&W offered its PW4098 and Rolls-Royce was proposing a Trent 8100. Rolls-Royce was also investigating another variant, the Trent 8102, which would produce over of thrust. By December 1997, the -300X grew to . The Trent 8104 design was to be completed by June 1998, while the -200X entry into service slipped to mid-2002. Higher thrust was obtained with new swept fan blades while keeping a fan.
The Trent 8104 first ran on 16 December 1998, and exceeded of thrust five days later, before two other engines would join by mid-1999. The swept fan blades produce 2–3% more flow at a given speed with the same fan, for an additional of thrust, while fan efficiency is 1% better. The HP compressor rotors and stators and the IP compressor stators were designed with 3D aerodynamics. As the 777-200X/300X grew to a MTOW of , thrust requirements drifted to . The fan diameter was to reach to increase the thrust.
By June 1999, the 8104 served as a basis for the proposed Trent 8115, with a scaled core by 2.5% geometrically and 5% aerodynamically and a fan enlarged from , while keeping the Trent 800 architecture: an eight-stage IP compressor and a six-stage HP compressor both driven by a single-stage turbine, and a five-stage LP turbine. In July 1999, Boeing selected the General Electric GE90 over the Trent 8115 and P&W offer to exclusively power the longer-range 777s, as GE offered to substantially finance the airframe's development, for around $100 million. Rolls-Royce later dropped the Trent 8115 but continued to work on the Trent 8104 as a technology demonstrator.
Trent 500
The Trent 500 exclusively powers the larger A340-500/600 variants. It was selected in June 1997, first ran in May 1999, first flew in June 2000, and achieved certification on 15 December 2000. It entered service in July 2002 and 524 engines were delivered on-wing until the A340 production ended in 2011. Keeping the three spool architecture of the Trent family, it has the Trent 700's fan and a Trent 800 core scaled down. It produces up to of thrust at take-off and has a bypass ratio up to 8.5:1 in cruise.
Trent 900
The Trent 900 powers the Airbus A380, competing with the Engine Alliance GP7000. Initially proposed for the Boeing 747-500/600X in July 1996, this first application was later abandoned but it was offered for the A3XX, launched as the A380 in December 2000. It first ran on 18 March 2003, made its maiden flight on 17 May 2004 on an A340 testbed, and was certified by the EASA on 29 October 2004. Producing up to , the Trent 900 has the same three shaft architecture of the Trent family with a fan. It has an 8.5–8.7:1 bypass ratio and a 37–39:1 overall pressure ratio.
Second Trent 600
In March 2000, Boeing was to launch the longer range 767-400ERX powered by engines, with deliveries planned for 2004. In July, Rolls-Royce was to supply its Trent 600 for the 767-400ERX and Boeing 747X, while the European Union was limiting the Engine Alliance offer on quadjets. The Trent 600 was scaled from the Trent 500 with a swept fan diameter raised to for a higher bypass ratio and lower fuel burn. Boeing offered the longer-range 767-400ERX with a higher MTOW and a higher thrust for better takeoff performance. The 767-400ERX was dropped in 2001 to favour the Sonic Cruiser. When Boeing launched the 747-8 in November 2005, it was exclusively powered by the General Electric GEnx.
Trent 1000
The Rolls-Royce Trent 1000 is one of the two engine options for the Boeing 787 Dreamliner, competing with the General Electric GEnx. It first ran on 14 February 2006 and first flew on 18 June 2007 before a joint EASA/FAA certification on 7 August 2007 and service introduction on 26 October 2011. The engine has a bypass ratio of over 10:1, a fan, and the three-shaft layout characteristic of the Trent series.
The updated Trent 1000 TEN with technology from the Trent XWB and the Advance3 aims for up to 3% better fuel burn. It first ran in mid-2014, was EASA certified in July 2016, first flew on a 787 on 7 December 2016 and was introduced on 23 November 2017. Corrosion-related fatigue cracking of IP turbine blades was discovered in early 2016, grounding up to 44 aircraft and costing Rolls-Royce at least £ million. By early 2018 it had a % market share of the confirmed order book. The Trent 7000 is a version with bleed air used for the Airbus A330neo.
Trent 7000
As a direct derivative of Trent 1000, the Rolls-Royce Trent 7000 exclusively powers the Airbus A330neo. Announced on 14 July 2014, it first ran on 27 November 2015, made its first flight on 19 October 2017 aboard on an A330neo, received its EASA type certification on 20 July 2018 as a Trent 1000 variant, was first delivered on 26 November, and was cleared for ETOPS 330 by 20 December. Compared to the A330's Trent 700, the engine doubles the bypass ratio to 10:1 and halves emitted noise. Pressure ratio is increased to 50:1 and it has a fan and a bleed air system. Fuel consumption is improved by 11%.
Trent 1500
When the MTOW A340-600HGW first flew in November 2005, Airbus was studying an enhanced version of the larger A340 variants to enter service in 2011. It would better compete with the 777-300ER and its 8–9% lower fuel burn than the A340-600: improved General Electric GEnx or Trent 1500 engines would erode this by 6–7%. The Trent 1500 would keep the Trent 500's fan diameter and nacelle, with the smaller, advanced Trent 1000 core and a revised LP turbine for a bypass ratio increased from 7.5–7.6:1 to 9.5:1. The last A340 was delivered in 2011 as it was replaced by the updated A350XWB design.
Trent XWB