Rolls-Royce Trent

Rolls-Royce Trent 900 on A380 prototype

Rolls Royce Trent is a family of high bypass turbofan engines manufactured by Rolls-Royce. All are developments of the RB211 with thrust ratings of between 53,000 and 95,000 lb_f (236 to 423 kN). Versions of the Trent are in service on the Airbus A330, A340, A380 and Boeing 777, and variants are in development for the forthcoming 787 and A350.

The Trent has achieved significant commercial success, being the launch engine for all three 787 variants, the A380 and A350. Its overall share of these markets is around 45%. Singapore Airlines is currently the largest operator of Trents with five variants in service or on order.

Earlier Trents

The Trent name has been used for two previous Rolls-Royce engines. The first Trent was the world's first turboprop engine. The name was reused again in the 1960s for the RB203 bypass turbofan which was designed to replace the Spey. It was the first three-spool engine, forerunner of the RB211 series. It was rated at 9980 lb_f (44.4 kN).

Present Trent

The current Trent is the development of the three-shaft RB211 family of engines, and revives the name after a 30-year gap. By 1987, a variant of the RB211, the RB211-524L, had been developed to such an extent that it bore little resemblance to the original RB211, other than the three-shaft layout. Rolls-Royce decided that the 524L would be the basis of a new engine family, and so the newest Trent was born.

Airbus gives all Rolls-Royce engined aircraft the designator "4"; eg. A330-342 or A380-841.

History

Background

When Rolls-Royce was privatised in April 1987, its share of the large civil turbofan market was only 8 per cent. Despite increasing sales success with the RB211, General Electric and Pratt & Whitney still dominated the market. At that time, the aircraft manufacturers were proposing new planes that were going to require higher levels of thrust than before. Furthermore the Boeing 777 and Airbus A330 were to be twin-engined, and their airline customers were demanding that they be capable of operating in the extended twin-engine operations environment (ETOPS) at the time of their initial introduction into service. Rolls-Royce decided that to succeed in the large engine market of the future, it would have to offer engines for every large civil airliner. In view of the enormous development costs required to bring a new engine to market, the only way to do this would be to have a family of engines based on a common core. The three-shaft design of the RB211 was an ideal basis for the new family as it provided flexibility, allowing the high-pressure (HP), intermediate-pressure (IP) and low-pressure (LP) systems to be individually scaled. Newly freed from the restrictions of state ownership, Rolls decided to launch the new family of engines, and the Trent was formally launched at the Farnborough Air Show in 1988.

Trent's versatile design has also been adapted for marine and industrial applications.

Rolls-Royce has obtained significant sums of 'launch investment' from the British government for the Trent programmes, including £200million approved in 1997 for Trent 8104, 500 & 600 and £250million for Trent 600 & 900 in 2001. No aid was sought for Trent 1000. Launch investment is repayable to the government by a royalty on each engine sold.

The revenues generated from sales of the Trent family of engines has made Rolls-Royce the second biggest supplier of large civil turbofans after General Electric.

Trent 600 - first proposal

The initial variant, Trent 600, was to power the McDonnell Douglas MD-11 with British Caledonian as the engine's launch customer. However, when British Airways bought British Caledonian in 1987, they cancelled the MD-11 order. With the collapse in 1991 of Air Europe in the aftermath of the 1990 Gulf War, the only other Trent-powered MD-11 customer was lost. As the MD-11 was itself suffering poor sales due to its failure to meet its performance targets, the Trent 600 was downgraded to a demonstrator programme, engine development being switched to the Trent 700, for the Airbus A330.

Trent 700

Emirates Airbus A330 with Trent 700 engines

When Airbus was planning its new twin-jet A330 in the late 1980s, Rolls-Royce at first proposed a version of the Trent 600 - the Trent 680 - to power it. However, as the A330's design weight increased, it became clear that more thrust would be required and Rolls proposed the Trent 720, the first member of the Trent 700 series. Cathay Pacific became its first customer when in April 1989 it ordered ten A330s powered by the Trent 700, making the A330 the first Airbus aircraft to be powered by Rolls-Royce engines. The following month TWA followed suit with an order for twenty A330s. The Trent 700 has the reputation of being the most environmentally friendly on the A330,being the quietest and cleanest available for this aircraft. The Trent 700 is the market leader on the A330,with a 49 per cent,share of orders and 42 customers and operators,worldwide.

Trent 800

At the same time Boeing were investigating an enlarged development of its 767 model dubbed the 767X, for which Rolls-Royce proposed the Trent 760. By 1990 Boeing abandoned its planned 767X and instead decided to launch a new, larger aircraft family designated 777 with a thrust requirement of 80,000 lbf or more. The Trent 700's 97.4 inch diameter fan would not be big enough to meet this requirement, so Rolls proposed a new version with a 110 inch fan diameter, designated Trent 800. Rolls brought in Kawasaki Heavy Industries and Ishikawajima-Harima Heavy Industries as risk and revenue sharing partners who between them took an 11 per cent stake in the Trent 700 and 800 programmes.

Singapore Airlines Boeing 777 with Trent 800 engines

The Trent 800 for the Boeing 777 was also launched by Cathay Pacific. However, initially, Rolls-Royce had difficulty selling the engine. British Airways, traditionally a Rolls-Royce customer, submitted a big order for the competing General Electric GE90 engine. The breakthrough came when the company won orders from Singapore Airlines, previously a staunch Pratt & Whitney customer, for its 34 Boeing 777s; this was soon followed by large North American orders from American Airlines and Delta Air Lines for their 777 fleets. Since then the Trent has established a reputation for being a very reliable engine with good after-sales support; British Airways announced in September 1998 that it was returning to Rolls-Royce for its second batch of 777s and again so in April 2007.B A,placed a follow on order for four firm aircraft and four options. The Trent 800 has a 43 per cent market share where it competes,on the 777.

Trent 8104

In 1998 Boeing proposed new longer range variants of the 777X; taking advantage of the Trent 800's growth capability, Rolls-Royce designed and built an improved engine designated Trent 8104 which was later scaled upwards to the even larger 8115. However, Boeing required that the participating engine developer assume a risk-sharing role on the overall 777X project. Rolls-Royce was unwilling to do so, and in July 1999 Boeing announced that it had chosen advanced developments of the GE90, the GE90-110B and GE90-115B to be the sole engines on the long-range 777s. This relegated the 8104 to the role of demonstrator engine.

Trent 500

Rolls-Royce Trent 500 on a Virgin Atlantic Airbus A340-600

In 1995 Airbus began considering an engine for two new long-range derivatives of its four-engined A340 aircraft, designated A340-500/-600. The existing -200 and -300 models were powered by CFM International CFM56 engines (which had been selected in April 1987 before the Trent family was launched). However, the CFM56 was at the limit of its development capability, and would be unable to power the new A340-500/-600. In April 1996 Airbus signed an agreement with General Electric to develop a suitable engine, but decided not to proceed when GE demanded an exclusivity deal on the A340. After a contest with Pratt & Whitney, Airbus announced on 15 June 1997 at the Paris Air Show that it had selected the Trent 500 to power the A340-500 and -600. The A340-600 entered service with Virgin Atlantic Airways in mid-2002, and the ultra-long range A340-500 with Air Canada in 2003. Airbus delivered 24 A340s in 2005 and 2006. In April/06, Kingfisher Airlines placed an order for five A 340 500s. Also, in June/07 Etihad Airways ordered four A340 600s,and Kingfisher Airlines a further five A 340 500s. Since the Trent 500 entered service in 2002,a total of 15 customers have placed firm orders for about 140 aircraft.

Trent 900

In the early 1990s Airbus had begun development of a larger successor to the Boeing 747, an aircraft designated A3XX, which was later to be formally launched as the A380. By 1996 its definition had progressed to the extent that Rolls-Royce was able to announce that it would devlelop the Trent 900 to power the A380. In October 2000, the Trent 900 received its first order when Singapore Airlines specified the engine for its order for 10 A380s; quickly followed by Qantas in February 2001. The Trent 900 made its maiden flight on May 17 2004 on Airbus' A340-300 testbed, replacing the port inner CFM56-5 engine, and its final certification was achieved on 29 October 2004. Rolls-Royce announced in October 2006 that production of the Trent 900 had been suspended for up to 12 months due to delays on the A380.

Trent 600 - second proposal

In July 2000 Rolls-Royce signed an agreement with Boeing to offer the Trent 600 engine on developments of 767 and 747 aircraft. The 767 variant was to be a new longer-range version of the Boeing 767-400ER to be powered by the Trent 600 and Engine Alliance GP7172, although in the end this aircraft was never launched. When Boeing finally launched the 747-8 in 2005 it announced that the General Electric GEnx would be the only engine available for the 747-8.

Trent 1000

File:AirNZ 789.jpg

787-9 in livery of the launch customer, Air New Zealand

On April 6, 2004 Boeing announced that it had selected two engine partners for its new 787: Rolls-Royce and General Electric. Initially, Boeing toyed with the idea of sole sourcing the powerplant for the 787, with GE being the most likely candidate. However potential customers demanded choices and Boeing relented. For the first time in commercial aviation, both engine types will have a standard interface with the aircraft, allowing any 787 to be fitted with either a GE or Rolls-Royce engine at any time.

As with earlier variants of the Trent family, Rolls partnered with risk and revenue sharing partners on the Trent 1000 programme. This time there were six partners: Kawasaki Heavy Industries (intermediate compressor module), Mitsubishi Heavy Industries (combustor and low pressure turbine blades), Industria de Turbo Propulsores (low pressure turbine), Carlton Forge Works (fan case), Hamilton Sundstrand (gearbox) and Goodrich Corporation (engine control system). Between them these partners have a 35 per cent stake in the programme.

In June 2004, the first public engine selection was made by Air New Zealand who chose the Trent 1000 for its two firm orders. In the largest 787 order, that of Japan's All Nippon Airways, Rolls-Royce was selected as the engine supplier on October 13, 2004. The deal is valued at $1bn (£560m) and covers 30 787-3s and 20 787-8s. The Trent 1000 is to be the launch engine on all 3 current 787 models, the -3 and -8 with ANA and the -9 with Air New Zealand.

The engine market for the 787 is estimated to be $40 billion USD over the next 25 years; The first run of the Trent 1000 was on 14 February 2006, with first flight on Rolls-Royce's own flying testbed (a modified Boeing 747-200) successfully performed on June 18th, 2007 from TSTC Airport in Waco, TX. Certification is expected in July 2007. On the 7/July/07 Rolls Royce secured an engine deal to power 40, 787 Dreamliner's,ILFC,has on order.[worth 1.3 Billion US Dollars] To date Rolls Royce has secured 198 firm orders for the 787 Dreamliner, Air New Zealand-8 aircraft,ANA-50 aircraft,Northwest-18 aircraft,LCAL-9 aircraft,LOT-8 aircraft,Icelandair-4 aircraft,Pegasus-6 aircraft,ILFC-10 aircraftAir China-15 aircraft,Monarch-6 aircraft,Boeing Business Jets-1 aircraft,CIT-2 aircraft,Aviamca-10 aircraft,VIP BBJ-1 aircraft,Blue Panorama-4 aircraft,Fly Globespan-2 aircraft.

Trent XWB

By 2004 Airbus was facing pressure from customers to develop a competitor for Boeing's 787, and in October 2005 formally launched the new aircraft designated A350, which was to be essentially an updated A330. Rolls-Royce offered a variant of the Trent 1000, dubbed Trent 1700 which would have been similar to the Trent 1000, but with a throttle-push to 75000lbf static thrust. Unlike the Trent 1000, the Trent 1700 would have been a conventional bleed-air engine, and would be developed in partnership with Kawasaki. After a lukewarm response from the airlines, Airbus reviewed their A350 proposal, and on 17 July, 2006 announced that they would be offering instead an all-new aircraft called the A350 XWB (eXtra Wide Body), with a fuselage diameter slightly greater than that of Boeing's 787, to compete with both the 787 and the 777.

Rolls-Royce has reached an agreement with Airbus to supply a new variant, currently called the Trent XWB (75000-95000lb_f static thrust), for the Airbus A350 XWB, and it will be offered on all versions of the aircraft. Initial Entry-into-Service will be on the A350XWB-900 in 2013, at a static thrust of 87000lbf, flat-rated to ISA+25C. General Electric has yet to confirm that it will offer a GEnx variant for the A350XWB. Flight International magazine has suggested that the GE/Pratt and Whitney Engine Alliance GP7200 may be the second engine option for the aircraft, at least on the smaller variants. On 18 June 2007, Rolls-Royce announced that it had signed its biggest ever contract with Qatar Airways for the Trent XWB to power 80 A350 XWBs on order from Airbus. To date,Rolls Royce has received 172 Airbus A350 firm orders, Alafco-12 aircraft,CIT-7 aircraft,Finnair-11 aircraft,Kingfisher-20 aircraft,Qatar-80 aircraft,Singapore Airlines-20 aircraft,US Airways-22 aircraft. The estimated addition to the Rolls Royce order book is 10.4 billion US dollars.

Design

Like its predecessor RB211, the Trent uses a three-spool design rather than the more common two-spool configuration. Although inherently more complex, it results in a lighter, shorter, more rigid engine which suffers less performance degradation in service than an equivalent twin-spool.

Although all the engines in the Trent family share a similar layout, their three-spool configuration allows each engine module to be individually scaled to meet a wide range of performance and thrust requirements. For example, the large 116 inch diameter fan of the Trent 900 keeps the mean jet velocity at Take-off at a relatively low level to help meet the stringent noise levels required by the Airbus A380's customers. Similarly, core size changes enable the (HP) turbine rotor inlet temperature to be kept as low as possible, thereby minimising maintenance costs. The overall pressure ratio of the Trent 800 is higher than the 700's despite sharing the same HP system and IP turbine; this was achieved by increasing the capacity of the IP compressor and the LP turbine.

The core turbomachinery is brand new, giving better performance, noise and pollution levels than the RB211. So significant were the improvements that Rolls-Royce fitted the Trent 700's improved HP system to the RB211-524G and -524H, creating -524G-T and -524H-T respectively.

When the RB211 programme originally started, it was intended that none of the compression system would require variable stators, unlike the American competition. Unfortunately, it was found that, because of the shallow working line on the IPC, at least one row of variable stators was required on the IPC, to improve its surge margin at throttled conditions. This feature has been retained throughout the RB211 and Trent series. Although the original intent was not met, Rolls-Royce eliminated the need for many rows of variable stators, with all its inherent complexity, thereby saving weight, cost and improving reliability.

Specifications

Trent 500 Series

The Trent 500 was designed to power the Airbus A340-500 and A340-600. It was certificated at 60,000 lb_f (267kN) thrust, but derated to 53,000 lb_f (236kN) as the Trent 553 to power the A340-500, and to 56,000 lb_f (249 kN) as the Trent 556 for the A340-600. However, a 60,000 lb_f (267kN) version is installed in the A340-600HGW (High Gross Weight), a higher-performance version of the A340-600. The Trent 500 has the same wide-chord fan as the Trent 700, together with a core scaled from the Trent 800.

• Three-shaft high bypass ratio 7.6 - 7.5
• Fan diameter: 97.4 inches (2.47 metres)
• Eight-stage IP compressor
• Six-stage HP compressor
• Tiled combustor with 20 fuel injectors
• Single-stage HP turbine
• Single-stage IP turbine
• Five-stage LP turbine

Trent 600 Series

This variant was announced but never produced - see History.

Trent 700 Series

The Trent 700 family was designed to power the Airbus A330. It comes in 2 thrust ratings, 67,500 and 71,000 lb_f (300 to 316 kN). It first entered service on Cathay Pacific A330s in March, 1995.

• Three-shaft high bypass ratio 5.0
• Fan diameter: 97.4 inches (2.47 metres)
• Eight-stage IP compressor
• Six-stage HP compressor
• Single annular combustor with 24 fuel injectors
• Single-stage HP turbine
• Single-stage IP turbine
• Four-stage LP turbine

Trent 800 Series

The Trent 800 family is designed to power the Boeing 777. It powers the 777-200, 777-200ER, and 777-300 variants. It is available with thrust ratings spanning 75,000 to 95,000 lb_f (334 to 423 kN).

The engine is one of the lightest in its class; a Trent-powered Boeing 777 weighs up to 3.6 metric tons less than General Electric and Pratt & Whitney-powered versions. The Trent 800 is the leading engine for the 777 with a 43% market share.

The Trent 800 was the first engine to be certified for ETOPS at entry into service. Since that time it has become a class leader for reliability, regularly returning a basic engine dispatch reliability of 99.9% which was a factor in securing 80% of installations on 777s since the start of 1997 and over 2 million flying hours since 1996.

• Three-shaft high bypass ratio 6.2 - 5.7
• Fan diameter: 110 inches (2.79 metres)
• Eight-stage IP compressor
• Six-stage HP compressor
• Single annular combustor with 24 fuel injectors
• Single-stage HP turbine
• Single-stage IP turbine
• Five-stage LP turbine

Trent 8104/8115

Originally designed for the 777-200LR and 777-300ER (both part of the 777X project), this engine comes in two thrust ratings, 104,000 and 114,000 lb_f (463 to 507 kN), and has been tested up to 117,000 lb_f (520 kN). As Boeing's thrust requirements increased, Rolls-Royce began developing the 115,000 lb_f 8115 which was to be an enlarged version of the 8104, with a 120 inch (3.048 metre) fan and a core scaled up 2.5 per cent from the 8104. It featured swept-back fan blades and a host of new technologies such as contra-rotating spools.

The 8115 was never built, as Boeing signed a contract with General Electric to be the sole supplier of engines for the 777X aircraft, owing to GEs willingness to risk-share on the airframe part of the project, and sales of the aircraft to GECAS.

Trent 900 Series

Rolls-Royce Trent 900 on test

The Trent 900 family is designed to power the Airbus A380, for which it is the launch engine. It comes in two thrust ratings, 70,000 and 76,000 lb_f (311 and 338 kN) but is capable of achieving 84,000 lb_f (374 kN). It features a significant amount of technology inherited from the 8104 demonstrator including its 2.95 m diameter swept-back fan which provides greater thrust for the same engine size, and is also about 15 per cent lighter than previous wide-chord blades. It is also the first member of the Trent family to feature a contra-rotating HP spool and uses the core of the very reliable Trent 500. It is the only A380 engine that can be transported on a Boeing 747 freighter.

Whereas most members of the Trent family are controlled by Goodrich FADECs, engine controllers on the Trent 900 are provided by Hamilton Sundstrand, a United Technologies (UTC) company. UTC is also the parent company of Pratt & Whitney, who, with GE Aircraft Engines, is partnering to produce the Engine Alliance GP7200, the other engine available for the A380. This kind of cooperation among competitors is prevalent in the aircraft market as it provides for risk sharing among them and diversity in source countries, a significant factor in an airlines' choice of airframe and powerplant.

The Trent 900 will be the first Trent engine fitted with the advanced Engine Health Monitoring (EHM) system based on QUICK Technology^TM.

• Three-shaft high bypass ratio 8.7 - 8.5
• Fan diameter: 116 inches (2.95 metres)
• Eight-stage IP compressor
• Six-stage HP compressor
• Tiled combustor
• Single-stage HP turbine
• Single-stage IP turbine
• Five-stage LP turbine

Trent 1000 Series

The technology found in the Trent 8104 demonstrator is used extensively. The Trent 1000 is a bleedless design, with power take-off from the intermediate-pressure spool instead of the high-pressure spool found in other members of the Trent family, to fulfill the Boeing requirements of a "more-electric" engine. A 112-inch diameter swept-back fan, with a smaller diameter hub to help maximize airflow, was specified. Bypass ratio has been increased over previous variants by suitable adjustments to the core flow. Contra-rotating the IP and HP spools improves IP turbine efficiency, while use of more monolithic parts reduces the parts count for lower maintenance costs. A tiled combustor is featured.

• Three-shaft high bypass ratio 11 - 10.8
• Overall pressure ratio (Top-of-Climb) 52:1
• Fan diameter: 112 inches (2.85 metres)
• Take-off thrust: 53000 - 75000 lbf (flat-rated to ISA+15C)
• Airflow: 2400 - 2670 lb/s
• Single-stage LP compressor
• Eight-stage IP compressor
• Six-stage HP compressor
• Tiled combustor
• Single-stage HP turbine
• Single-stage IP turbine
• Six-stage LP turbine
• Certification: 2007
• EIS: 2008

Trent 1500 Series

A Trent 500 replacement engine, known unofficially as the Trent 1500, has been proposed for the Airbus A340-500/600, to help the aircraft compete with the Boeing 777-200LR/300ER. However, the announcement of the A350XWB, which covers the A340 market, may prevent the Trent 1500 from ever becoming a reality.

The Trent 1500 would retain the 97.4in fan diameter of the current Trent 500 engine, as well as the nacelle, but incorporate the smaller, more advanced, Trent 1000/XWB gas generator and LP turbine, suitably modified.

Trent XWB

Originally intended to have the same 112in diameter fan of the Trent1000/Trent1700, Rolls-Royce have now announced an increase in diameter to 118in for the Trent XWB, to keep the take-off jet noise acceptable at the increased thrust level. The company will probably also have to increase the core flow, to moderate the HP turbine rotor inlet temperature. They are unlikely to increase overall pressure ratio significantly to gain core flow, because this parameter is already very high, so some increase in core size is almost inevitable.

• Three-shaft high bypass ratio:
• Fan diameter: 118 inches (3.0 metres)
• Fan:single stage, swept, low hub:tip ratio
• IP compressor:7 stage axial
• HP compressor:6 stage axial
• Combustor:
• HP turbine:single-stage, aircooled
• IP turbine:single-stage
• LP turbine:6-stage, uncooled
• Certification:2012
• EIS: mid-2013

Leading Particulars

Trent Engine Family:Leading Particulars
	Trent553	Trent556	Trent600	Trent768	Trent772	Trent875	Trent877	Trent884	Trent892	Trent8104	Trent970	Trent977	Trent1000	TrentXWB
Static Thrust (lbf)	53000	56000	65000	67500	71100	77900	80270	86910	91450	104000	70000	76500	75000	95000
Basic Engine Weight (lb)	10400	10400	~10400	10550	10550	13100	13100	13100	13100	14400	13825	13825	11924	?
Length (in)	154	154	154	154	154	172	172	172	172	172	179	179	160	?
Fan Diameter (in)	97.4	97.4	97.4	97.4	97.4	110	110	110	110	110	116	116	112	118

Marine Versions

Main article: Rolls-Royce Marine Trent

MT30

The Marine Trent 30 is a derivative of the Trent 800, (with a Trent 500 gearbox fitted), producing 30 megawatts (MW) for maritime applications. The current version is a turboshaft engine, producing 36 MW, using the Trent 800 core to drive a power turbine which takes power to an electrical generator or to mechanical drives such as waterjets or propellers.

External links

• Rolls-Royce plc
  • Trent 500 series
  • Trent 700 series
  • Trent 800 series
  • Trent 900 series
  • Trent 1000 series
  • Trent XWB
  • MT30