The Rolls-Royce Trent 900 is a series of turbofan engines, developed from the
RB211 and is one of the family of Trent engines. It is one of the powerplant
options available for the Airbus A380, along with the Engine Alliance GP7000.
Design and development In the early 1990s, Airbus had begun
development of a larger competitor 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 develop the Trent 900 to power the A380. In October 2000, the
Trent 900 became the A380's launch engine when Singapore Airlines specified
the engine for its order for 10 A380s; this was quickly followed by Qantas in
February 2001. Rolls-Royce has seven risk and revenue
sharing partners on the Trent 900: Industria de Turbo Propulsores, Hamilton
Sundstrand, Avio S.p.A., Marubeni Corporation, Volvo Aero, Goodrich
Corporation and Honeywell. In addition, Samsung Techwin, Kawasaki Heavy
Industries and Ishikawajima-Harima Heavy Industries are programme associates.
The Trent 900 made its maiden flight on 17 May 2004 on Airbus' A340-300 testbed,
replacing the port inner CFM56-5 engine, and its final certification was granted
by EASA on 29 October 2004 and the FAA on 4 December 2006. Rolls-Royce
announced in October 2007 that production of the Trent 900 had been
restarted after a twelve-month suspension caused by delays to the A380.
On 27 September 2007, British Airways announced the selection of the Trent 900
to power 12 A380 aircraft, helping to take the engine's share of the A380
engine market to 52% at the end of February 2009.
The Trent 900 family powers the Airbus A380. It comes in two thrust ratings for
the A380, 310 kN and 320 kN but is capable of achieving 360 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 percent 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
whole. 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 company. UTC is also
the parent company of Pratt & Whitney, who, with GE Aircraft Engines, is
partnering to produce the Engine Alliance GP7000, 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, which may be a significant factor in an airline's
choice of airframe and powerplant. The Trent 900 will be the first Trent
engine fitted with the advanced Engine Health Monitoring system based on QUICK
Technology. Variants
Trent 970B- 84 with 348.31 kN of thrust. In use by A380-841 of Singapore
Airlines, Lufthansa, China Southern Airlines and Malaysia Airlines.
Trent 972B- 84 with 356.81 kN of thrust. Higher thrust variant of the 970, in use
by A380-842 of Qantas. Trent 977B- 84 with 372.92 kN of thrust.
Variant for A380-843F. Trent 980- 84 with 374.09 kN of thrust.
Higher thrust variant for A380-941. Upgrades
The Trent 900 family of engines had their first set of upgrades marketed as
the Trent 900EP; these were available for delivery from 2012. This package
delivered a 1% saving on fuel burn compared to non EP engines. While one
source states that this package is not available as a retro fit to previously
delivered engines, Rolls Royce told Aviation Week and Space Technology that
the upgrades were intended in most cases for both new engines and as retrofits.
This upgrade is based on advancements made during the development of the Trent
XWB and matches improvements made for the Trent 700 called the Trent 700EP.
Block 1 includes elliptical leading edges in the compressor, smaller
low-pressure turbine tip clearances, and new coating for the high pressure
compressor drum, as well as an upgrade to the engine control software.
The EP2 package entered testing in May 2013 and is scheduled to be available
for delivery in mid 2014. This package aims to provide a further 0.8% reduction
in fuel burn on top of the improvements offered by the EP package. Changes
include better sealing of the low pressure turbine, improvements to fan
blade tip clearances, and other changes derived from the engines developed for
the Boeing 787 and Airbus A350. EP2 passed a type certificate test by
European Aviation Safety Agency on the 27th November 2013 and an update type
certificate was issued on 11 December 2013.
Applications Airbus A380
Notable incidents On 4 November 2010, a Trent 972 powered
Airbus A380-842 of Qantas Flight QF32 suffered an uncontained engine failure
in engine number 2 en route from Singapore to Sydney and returned to
Singapore Changi Airport where it landed safely. Qantas grounded its fleet of six
A380s for over three weeks after the accident pending the investigation and
said it may replace up to 16 engines after identifying potential problems.
VH-OQA was repaired at an estimated cost of A$139 million. The aircraft has four
new engines, a repaired left wing, and had extensive onground testing and two
test flights. It returned to service on 28 April 2012.
On 10 November 2010, the European Aviation Safety Agency issued an
Emergency Airworthiness Directive, ordering airlines using the Trent 900
engine to conduct frequent and stringent tests, including extended ground idle
runs, Low Pressure Turbine stage 1 blade and case drain inspections and HP/IP
structure air buffer cavity and oil service tube inspections. However, on 22
November 2010, the EASA eased its inspection guidelines, citing progress
in the investigation. It dropped requirements for extended ground idle
runs and requirements for repetitive inspections of the LPT stage 1 blades
and case drain. An investigation by Rolls-Royce
concluded that the accident was caused by an oil fire and was confined to a
specific component in the turbine area of the engine. The fire led to the
release of the Intermediate Pressure Turbine disc. It also said the issue is
specific to the Trent 900. Airbus determined that the IPT disk
released 3 different high energy fragments, resulting in some structural
and systems damage. It also concluded that segregated wiring routes were cut
by 2 out of the 3 individual disk debris and as a result, engine 1 could not be
shut down after landing. On 18 November, Airbus announced it may
seek compensation from Rolls-Royce for any disruption caused by the Qantas
incident and the plans to reassign engines.
In a preliminary investigation report of the engine failure of Qantas Flight
QF32, released 3 December 2010, the Australian Transport Safety Bureau
outlined safety actions taken already, including the issuing of a safety
recommendation about potential engine problems with the Trent 900. The safety
recommendation relates to a possible manufacturing issue with a misaligned
counterbore in some pressured oil pipes, which could lead to fatigue cracking,
oil leakage, oil fire, and engine failure.
Qantas claims that thrust restrictions recommended by Rolls-Royce following the
engine failure have led to severely reduced payloads, making routes
unprofitable. Specifications
General characteristics Type: Three-shaft high bypass ratio
turbofan engine Length: 5.48 m tip of spinner minus
rubber tip to Tail Bearing Housing Plug Mount Flange
Diameter: 2.95 m LP compressor fan Dry weight: 6,246 kg
Components Compressor: Single stage LP, Eight-stage
IP compressor, six-stage HP compressor Combustors: Single annular combustor
Turbine: Single-stage HP turbine, single-stage IP turbine, five-stage LP
turbine Performance
Maximum thrust: 344–357 kN or 77,000–80,000 lbf
Overall pressure ratio: 37–39 Thrust-to-weight ratio: 5.46–6.11 mass /
weight of engine and certified to 334–374 kN or 75,000–84,000 lbf of
thrust) Source: EASA Type Certificate
Cost In 2000 Qantas were quoted a price of
US$12.85 million per Trent 900. In 2012 Skymark Airlines signed a contract for
24 Trent 900s including long-term TotalCare® service support at a cost of
US$1 billion. See also
Comparable engines Engine Alliance GP7000
Related lists List of aircraft engines
References External links
Rolls-Royce plc – Trent 900 FAA Trent 970 type certificate data
sheet