Rolls-Royce

Un Airbus A380 de la compagnie aérienne Qantas Airways a dû se poser en urgence à Dubaï ce matin après avoir rencontré un problème d’huile sur l’un de ses réacteurs.

Vendredi 4 novembre 2011, un an jour pour jour après l’explosion d’un
réacteur peu après le décollage du superjumbo de la compagnie nationale
australienne à Singapour, l’équipage de l’A380 reliant Singapour à
Londres a signalé un « défaut de quantité d’huile » sur l’un de ses
quatre Rolls Royce Trent 900, et s’est posé en urgence
mais sans problème à Dubaï. Le vol QF31 transportait 258 passagers,
quatre pilotes et 21 personnels de cabine.

Qantas Airways n’en est pas à son premier problème avec les réacteurs
Rolls Royce: sans parler de l’incident de Singapour, un vol Singapour –
Londres en A380 s’était terminé sur trois moteurs le 18 février dernier
(durite d’huile mal remise en place), et quatre vols en Boeing 747
équipés de RB-211 avaient connu des problèmes en janvier.

La compagnie de l’alliance Oneworld annonçait par
ailleurs en juin dernier que la livraison d’une paire d’A380 serait
repoussée de deux à trois mois, justement à cause des problèmes
rencontrés sur les Trent 900. Elle opère actuellement neuf superjumbos
sur 20 commandés, le dixième livré étant toujours bloqué à Singapour.

Qantas n’est pas la seule à avoir des problèmes avec ces réacteurs: Singapore Airlines a interrompu en juillet un Singapour – Hong Kong suite à de fortes vibrations. L’Agence Européenne de la Sécurité Aérienne (EASA)
a par ailleurs émis une directive d’aptitude au vol (airworthiness)
concernant un compartiment des pylônes soutenant les Trent 900, qui dans
certains cas chaufferaient trop et pourraient déclencher un incendie en
cas de fuite hydraulique importante.

Rolls Royce motorise 10 des 15 compagnies à avoir commandé le superjumbo (les susnommées plus Asiana Airlines, British Airways, China Southern Airlines, Lufthansa, Thai Airways, Malaysia Airlines et Virgin Atlantic, plus un client privé), même si sa part de marché est minoritaire. Le plus gros client de l’A380, Emirates Airlines, est équipé par son rival le GP7200 d’Engine Alliance (tout comme Air France, Air Austral, Etihad Airways et Korean Air).
http://www.air-journal.fr/2011-11-04-encore-un-probleme-moteur-pour-la380-de-qantas-538752.html

With the first version of the Trent XWB engine for the A350 poised for the start of test flights, Rolls-Royce is already stepping up studies of what comes next in its big engine line-up.
One key question is whether the recent birth of the new Rolls-Royce mid size engine joint venture with Pratt & Whitney will increase the chances of geared technology spreading to the next generation of higher thrust turbofans beyond the Trent XWB? For now it seems unlikely, mainly because Rolls believes its existing three-shaft architecture provides multiple jumping-off technology options for improving both thermal and propulsive efficiency.
However geared technology in longer term Rolls engine will not be limited to the mid-thrust range. Both General Electric and Rolls have acknowledged that the appeal of the GTF concept increases in proportion to thrust. Even before the newly forged relationship with Pratt was announced in October, Rolls openly said ultra-high bypass ratio geared fans may be required to meet the challenging targets of future emissions goals such as those outlined in the European Union’s Flightplan 2050 vision for future air transport.
Overall Rolls shows no signs of diverging from the guidelines of its existing research strategy which, early last decade, grouped technology acquisition within three broad, rolling time bands – up to around five years, around ten years, and up to 20 years and beyond. This it calls its Vision 5, Vision 10 and Vision 20 programs, with Vision 5 originally covering engines such as the Trent 900 for the A380, and later the Trent 1000 for the 787.



Study concepts include a bladed spinner (Rolls-Royce)

Rolls basis its future near term big engine development squarely on the Vision 10-derived Trent XWB architecture and is starting to reveal more details about what the technology options are. Speaking at this year’s International Society For Air Breathing Engines meeting in Sweden, Rolls Future Programs senior project engineer John Whurr, says “the core architecture of the Trent XWB, in particular the two-stage intermediate turbine, facilitates development of the core thermodynamic cycle.”
It does this, he adds, by enabling increased compressor pressure ratios, and overall pressure ratio, without compromising the efficiency of the high and intermediate pressure turbines. Improvements in the core could also come from introducing a ‘cooled’ cooling air system to enable higher compressor temperatures without compromising component lives. Higher turbine inlet temperatures, and hence better thermodynamic efficiency, could be gained by introducing ceramic matrix composites in the turbine.


Other concepts include a 'mini-mixer'. (Rolls-Royce)

Driven by the need to be greener, Rolls sees an increasing trend towards lower specific thrust and improved propulsive efficiency. The low pressure system will play a big role in this with the likely adoption of lightweight composite fan blades and containment casings, lighter LP turbines using advanced materials such as titanium aluminide, as well as slimline nacelle concepts that will mitigate the drag and weight of the larger diameter engines of the future.
Further advancements under study include increased use of fuel as a heat sink, greater use of CMCs and possibly the introduction of variable area exhaust nozzles similar to those in development for the PW1000G.
It is the raft of technologies under consideration for the longer term ‘Vision 20’ period that begin to stir the imagination. They include intelligent control systems with advanced prognostics/diagnostics and connectivity, as well as a fuel-cooled intercooler. For the first time in more than a decade, the engine could also look significantly different with radical changes to the fan. Rolls is studying a bladed spinner, for example, which integrates the root of the fan blades with the spinner in an arrangement which “allows us to squeeze more flow through a fan of given size,” says Whurr.
Internally, the Vision 20 engine could feature stator-less contra-rotating high and intermediate pressure turbines and a casing for the intermediate pressure compressor formed from a bladed drum made from metal matrix composites. It could also be configured with all-ceramic, self-diagnostic bearings and embedded centerline electric motors/generators.
To further boost efficiency, Rolls is also studying a novel concept called a mini-mixer, which would be wrapped around the aft casing. The forced mixer would be “one of the best ways to improve transfer efficiency” between the core stream and bypass stream says Whurr. Taken as a whole, the studies show there is no shortage of ideas when it comes to squeezing yet more efficiency out of conventional turbofans.

Rolls-Royce pushes new engine concept for 777X

Rolls-Royce has unveiled its all-new RB3025 engine concept for
the 777X, responding to the airframer's 2011 request for information
issued to itself, GE and Pratt & Whitney for Boeing's conceptual
widebody.

"Boeing asked the three engine [manufacturers] what we could do in
terms of product for what is now called the 777X, at around the end of
this decade," says Rolls Royce vice-president of strategic marketing,
Robert Nuttall.

Most observers predicted that GE would retain the exclusivity it
currently enjoys with its GE90 which powers the 777-300ER, -200LR and
Freighter, on Boeing's next-generation 777, by offering its conceptual
GE9X. However, the emergence of additional proposals kicks off what is
likely to be a fierce battle to power the 777X-family of aircraft.

Rated at 99,500lbs with a 337cm (132.5in) fan for the baseline
407-seat 777-9X, giving the RB3025 a bypass ratio of 12:1, Rolls touts a
"better than 10%" improvement in fuel burn over the incumbent GE90-115B
engine and 15% better than its Trent 800 which powers early model 777s.

Rolls says the current concept provides a low specific thrust and
"excellent" propulsive efficiency, along with a 62:1 overall pressure
ratio, which, if achieved, would be the highest OPR demonstrated in a
commercial turbofan engine.

The RB3025 builds on the Trent 1000 and XWB engines, but Nuttall says
the concept is built around its Advance3 environmentally friendly
engine (EFE) technology development programme, which includes a Trent
1000-derived core, lean-burn combustor, composite fan and advanced
materials in the combustor and high pressure elements of the core.

"We're pleased to be dependent on Boeing's decision-making here,"
says Nuttall of a development schedule. "We're targeting an end of the
decade timescale, but that will be entirely down to what Boeing tells
us. Then obviously we'll work backwards from that date."

Boeing declines to say whether or not it will offer multiple engine
choices for the 777X: "It would have to be a programme before we made a
decision like that," it says.

The airframer aims for a late-2012 official launch from the company's board of directors.

The 777-8X concept, a 353-seat stretch of the 777-200ER, would have a
thrust requirement of 88,000lb and Nuttall says Rolls aims to have a
"single bill of materials" for the RB3025 engines on both the -8X and
larger -9X, in which the lower thrust is achieved through a simple
engine de-rate.

Nuttall says Rolls will take the next "year or two" of design work
with Boeing to optimise the engine around the conceptual aircraft,
requiring roughly six years ahead of a service entry to fully develop a
new engine.

"The design is already quite comprehensive, but we would flesh that
out in more and more detail, getting much more down to component level
[design]," says Nuttall of its plans for 2012.

"The design we've got, most people wouldn't be able to tell the
difference between [the RB3025] and the finished engine. We've got
tremendous amounts of detail that we're sharing with Boeing currently,"
he adds.

Rolls has historically voiced its opposition to aircraft re-engining
programmes, though the company looks to enthusiastically pitch the
RB3025 for the re-winged, re-engined 777X, citing the aircraft's new
composite wing as a key component for achieving the overall optimisation
the engine maker prefers when making such a large-scale investment.

"As far as fuel burn is concerned, the wing on an aircraft is the
predominant technology, I think we're quite comfortable that 777X is a
re-optimised aircraft with a new wing and new engine.

"That's not just the same as only optimising the engine for example. We're very comfortable with this position," says Nuttall.
http://www.flightglobal.com/news/articles/rolls-royce-pushes-new-engine-concept-for-777x-369294/

Rolls-Royce, Pratt & Whitney close IAE restructuring


Rolls-Royce and Pratt & Whitney have completed their
restructuring of the International Engine Alliance partnership, with R-R
formally selling its 32.5% equity stake in the IAE V2500 programme to
P&W for $1.5 billion.


As previously announced, the two are
also setting up a new joint venture, subject to separate regulatory
approval, to develop high-bypass ratio geared turbofan technology to
power future mid-size aircraft in the 120-130-seat segment. IAE partners
Japanese Aero Engines and MTU are to join the new joint venture. MTU,
which currently owns 11% of the V2500 programme, will raise its share by
purchasing some of the former R-R stake from P&W.
Under the
terms of the IAE deal, R-R will receive an agreed payment for each hour
flown by the current installed fleet of V2500-powered aircraft for the
next fifteen years.
R-R's civil aerospace operating profit will be
boosted by more than £140 million in the coming 12 months; the company
expects a slowly diminishing profit improvement after that, depending on
utilisation of the V2500 fleet.
P&W's geared turbofan
technology, in the PurePower PW1000G family of engines, will power the
Bombardier CSeries, Mitsubishi Regional jet, Irkut MS-21 and is an
option on the A320neo. But the next generation of engines will feature
larger fan diameters and greater bypass ratios.
R-R, meanwhile
will continue developing its own next-generation engine concepts: the
two-spool Advance2 for the mid-size aircraft sector, the three-spool
Advance3 for large aircraft and the open rotor engine.



http://www.flightglobal.com/news/articles/rolls-royce-pratt-whitney-close-iae-restructuring-373567/