Rolls-Royce Trent XWB
| Company type | Turbofan aircraft engine |
|---|---|
| Industry | Aerospace |
| Founded | June 14, 2010 |
| Founder | Rolls-Royce Holdings |
| Products | Aircraft engines |
| Parent | Rolls-Royce Holdings |
The Rolls-Royce Trent XWB is a high-bypass turbofan engine developed by Rolls-Royce Holdings. Chosen exclusively in July 2006 to power the Airbus A350, it underwent its initial run on 14 June 2010, made its first flight on an A380 test platform in February 2012, received certification in early 2013, and entered operational service with the A350 in June 2013. After accumulating 2.2 million flight hours, the engine experienced its inaugural in-flight shutdown in September 2018. It maintains the signature three-shaft configuration typical of the Rolls-Royce Trent series, incorporating fan, intermediate-pressure, and high-pressure spools. Producing , it features a 9.6:1 bypass ratio and an overall pressure ratio of 50:1, establishing it as the most powerful variant within the Trent family.
Development
By 2004, Airbus was under considerable pressure to develop an aircraft to rival the Boeing 787 Dreamliner, leading to the launch of the A350 in October 2005 as an enhanced version of the A330. Rolls-Royce initially offered a conventional bleed air engine derived from the Trent 1000, designated the Trent 1700, delivering thrust. However, after Airbus redesigned the A350 in 2006, Rolls-Royce secured a contract to supply all A350 variants with the newly developed Trent XWB, providing thrust ranging from to .
Prior to the design freeze in December 2008, Airbus discovered that the A350’s empty weight exceeded projections by , which necessitated an increase of in maximum takeoff weight (MTOW) to maintain payload and range capabilities. In response, Rolls-Royce augmented the engine’s nominal thrust by , with Airbus reporting negligible effects on fuel efficiency. By 2011, further thrust uprating elevated the output for the largest A350 model to , improving its competitiveness against the Boeing 777-300ER.
Testing
The Trent XWB underwent its first static test on 14 June 2010. Airbus announced on 18 February 2012 that the engine had completed its maiden flight aboard a dedicated Airbus A380 testbed. By October 2012, it was anticipated that the engine would enter service in 2014, with early versions certified by early 2013. The Trent XWB powered its initial flight on the Airbus A350 XWB on 14 June 2013.
On 15 May 2014, Rolls-Royce delivered the first production Trent XWB engines rated at thrust for the initial Airbus A350 XWB entering service with Qatar Airways. Assembly of these engines began in February 2014. Later, on 15 July 2014, Rolls-Royce announced successful testing of the higher-thrust Trent XWB-97 variant producing thrust for the Airbus A350-1000.
Operations
By 26 July 2017, Airbus had delivered its hundredth A350 aircraft and aimed to reach a monthly production rate of ten by late 2018. Early engine removals primarily served data acquisition or maintenance scheduling purposes; approximately 90% of Trent XWB engines operate under long-term service agreements with Rolls-Royce. The company designates seven maintenance repair and overhaul (MRO) providers including its Derby facility and partnerships with entities such as HAECO, SIAEC, as well as independent operators like Delta TechOps, Mubadala, and Air France Industries-KLM. By October 2017, Trent XWB engines had accumulated over one million flight hours while maintaining a dispatch reliability of 99.4%.
By February 2018, total flight hours reached approximately 1.3 million with dispatch reliability increasing to 99.9%. The fleet's cumulative flying time doubled from one million to two million hours within nine months by July 2018 following delivery of around 500 engines; dispatch reliability remained at an impressive 99.9%, with no recorded in-flight shutdowns during this period. However, upon reaching around 2.2 million total flight hours, an Iberia-operated A350-900 experienced an inflight shutdown in September 2018 caused by minor damage to variable stator vanes.
In 2019, unit losses for the XWB-84 model decreased by more than twenty percent, with Rolls-Royce projecting break-even financial performance by late 2020; some leading engines had surpassed 22,000 operational hours without requiring shop visits. Conversely, the higher-thrust XWB-97 variant powering the A350-1000 remained unprofitable, although extended time-on-wing was viewed as a potential path to improved viability.
During the 2023 Dubai Airshow, Emirates president Tim Clark criticized the Trent XWB-97 for offering only about one-quarter of the maintenance interval expected by operators—a statement analysts interpreted as part of commercial negotiations concerning pricing or warranty terms. They noted that this higher-thrust version operates at elevated temperatures which accelerate wear rates, particularly under hot and dusty environments; however, Qatar Airways reportedly operates this engine without significant issues. Rolls-Royce is actively collaborating with Emirates to enhance engine durability under these challenging conditions.
On 2 September 2024, a Cathay Pacific A350-1000 powered by a Trent XWB suffered an inflight engine fire but managed a safe landing. Subsequent inspections across Cathay’s entire fleet of forty-eight A350s uncovered several aircraft exhibiting similar defects involving damaged flexible fuel lines. As a result, the European Union Aviation Safety Agency mandated a one-time inspection of all Trent XWB engines following this event.
Design
The Trent XWB is an axial flow, high bypass turbofan engine that preserves the distinctive coaxial three-shaft configuration characteristic of the Rolls-Royce Trent series. Its fan is powered by a 6-stage turbine, while the 8-stage intermediate-pressure compressor is driven by a 2-stage turbine. The 6-stage high-pressure compressor is rotated by a single-stage turbine that spins in the opposite direction to the other shafts. The engine incorporates an annular combustor equipped with 20 fuel spray nozzles and employs dual-channel FADEC. Unlike earlier Rolls-Royce Trent models, this design includes a 2-stage IP turbine rather than a single stage.
For the A350-1000 model, the variant retains the same 3-meter diameter fan but features a core enlarged by 5%. To generate increased thrust, the fan operates at a speed 6% higher, necessitating thicker titanium fan blades, reinforced casing, and innovations developed through the European Environmentally Friendly Engine (EFE) initiative. Additionally, this version supports a higher core operating temperature.
Orders
On 18 June 2007, Rolls-Royce finalized a $5.6 billion agreement with Qatar Airways to supply engines for 80 Airbus A350 XWBs, with each engine averaging $35 million in value.
In November 2007, Rolls-Royce announced a significant contract with Emirates for 70 Trent XWB engines—50 designated for A350-900 and 20 for A350-1000 aircraft—with an estimated list price total of $8.4 billion including options. This order was subsequently canceled by Emirates in June 2014.
By July 2015, sales had surpassed 1,500 Trent XWB engines across 40 clients. Rolls-Royce proposed a £340 million maintenance package to Vietnam Airlines covering 14 aircraft, averaging around £12 million per engine.
On 15 December 2023, Rolls-Royce revealed that Turkish Airlines placed an order for 100 XWB-84 and 40 XWB-97 engines. Combined with its existing fleet of 66 Trent engines, Turkish Airlines became the largest operator of Trent XWB powerplants with nearly 210 units in service.
Variants
| Designation | Certification Date | Net Take-off Thrust | Net Maximum Continuous Thrust |
|---|---|---|---|
| Trent XWB-75 | 7 February 2013 | 74,200 lbf (330 kN) | 66,600 lbf (296 kN) |
| Trent XWB-79 | 7 February 2013 | 78,900 lbf (351 kN) | 71,400 lbf (318 kN) |
| Trent XWB-79B | 7 February 2013 | 78,900 lbf (351 kN) | 71,400 lbf (318 kN) |
| Trent XWB-84 | 7 February 2013 | 84,200 lbf (375 kN) | 71,400 lbf (318 kN) |
| Trent XWB-97 | 31 August 2017 | 97,000 lbf (430 kN) | 83,100 lbf (370 kN) |
Specifications
| Parameter | -84 Variant | -97 Variant | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Engine Type | Three-shaft axial flow turbofan with high bypass ratio | |||||||||||||||||||||||||
| Fan Details | Single-stage fan, diameter of 3.00 m (118 inches), featuring 22 blades with swept design and low hub-to-tip ratio | |||||||||||||||||||||||||
| Compressor Configuration | Eight-stage intermediate-pressure compressor and six-stage high-pressure compressor | |||||||||||||||||||||||||
| Combustor Type | Annular combustor containing twenty fuel spray nozzles | |||||||||||||||||||||||||
| Turbine Arrangement | Single-stage high-pressure turbine; two-stage intermediate-pressure turbine; six-stage low-pressure turbine; air-cooled HPT and IPT; uncooled LPT | |||||||||||||||||||||||||
| Overall Length | 5,812 mm (228.8 inches) measured from spinner tip to cold nozzle rear | |||||||||||||||||||||||||
| Dry Weight | 7,277 kg (16,043 lb) | 7,550 kg (16,640 lb) | ||||||||||||||||||||||||
| Takeoff Thrust Rating | 84,200 lbf (375,000 N) | 97,000 lbf (430,000 N) | ||||||||||||||||||||||||
| Cruise TSFC |
0.478[convert: needs unit name] |
Specific Impulse |
"7,530 s" |
Rotor Speeds (RPM) | "LP: 2700; IP: 8200; HP: 12600" | "LP: 2700; IP: 8200; HP: 12600" | Bypass Ratio | "9.6:1" | "9.6:1" | Overall Pressure Ratio | "50:1" | "50:1" | Thrust-to-Weight Ratio | "5.22" | "5.81" | Air Mass Flow | "1,436 kg/s (3,166 lb/s)" | |||||||||