Boeing's widebody plans will test Rolls-Royce's bet on big engines
's decision to retrench from the narrowbody engine market has raised the stakes on the company's big powerplant activities. The coming months could show whether that bid is paying off as refines its widebody strategy.
Boeing continues to deliberate whether to add a larger model—the -10X— to the 787 family, even as it explores refresher options for the 777 family to ward off end-of-decade competition from the-1000. “Quite detailed” discussions are underway with Boeing over a version to power the 787-10X, says Simon Carlisle, Rolls-Royce's program director. The powerplant will be roughly in the 76,000-lb.-thrust class, although the exact figure is not settled.
The 315-323-seat aircraft represents a simple stretch of the, says Jim Haas, marketing director at (BCA). It would be effectively about 40 seats larger than the -9 and be ready to enter service later in the decade. Whether Boeing will launch the 787-10X at the Farnborough International Airshow, which opens next week, is unclear, particularly in light of the surprise decision last week to name Raymond Conner, head of sales at Boeing Commercial Airplanes, as the replacement for BCA CEO and President James Albaugh (see p. 31).
Rolls-Royce would look to introduce technologies now incorporated in the TrentXWB for the A350 but not yet on the Trent 1000. A few additional technologies that have matured more recently could also be included, to achieve a 1-2% fuel-burn improvement over the so-called Package C Trent 1000s.
The “Study Engine” that would incorporate the feature could emerge in 2016. Rolls-Royce is in the process of freezing the concept before proceeding to a critical design review in about six months.
At the same time, the company is in talks with Boeing about the RB3025, a 100,000-lb.-thrust engine concept for the/-9 Boeing is studying. The aircraft maker is talking with Rolls-Royce, Pratt & Whitney and its exclusive 777-300ER engine supplier— —about new engines for the larger twin-widebodies.
The RB3025 would feature a range of new technologies, including a composite fan blade and composite casing, says Robert Nuttall, Rolls-Royce vice president for strategic marketing. Rolls has been using titanium fans, arguing its design was as efficient as the composite fans being offered by competitors. But Nuttall now says that composites technology has improved and fan blades and casings made of composites promise several hundred pounds in weight savings.
The RB3025 would have a 132.5-in.-dia. fan delivering a 12:1 bypass ratio. The overall pressure ratio would reach 62:1. It is “quite an aggressive engine,” Nuttall argues, which should be ready toward the end of the decade. It would feature a rising line compressor, a change in architecture now being introduced in the TrentXWB.
Mark King, president of civil aerospace at Rolls-Royce, stresses that even with last year's decision to exit theInternational Aero Engines joint venture powering the Airbus (Rolls remains a parts supplier), the U.K.-based engine maker is “not going to be short of things to do. The challenge is going to be how do we deploy resources.”
If Rolls-Royce can secure a place on the new Boeing product—still unclear is whether it would be a new design or merely an update to the 777—the engine maker would dominate its rivals in the large turbofan market with its sole position on the A350-900/-800, exclusivity on the A350-1000, and shared market on the Boeing 787 where the Trent 1000 competes with the, and on the where the is up against the GE/Pratt & Whitney GP7200.
With its newest large engine, the TrentXWB, now in trials on the A380 flying testbed, the configuration will likely be locked in soon for the largest model, the 97,000-lb.-thrust version for the A350-1000, says Chris Young, program director for the TrentXWB. The first engine is slated to run in 2014.
The final technology trades are still being made. Young says some of the technologies that have been under review in the past few years have materialized and others have not. But, he adds, “enough of them have come through . . . to deliver the engine concept.”
At the same time, the company also is working on the latest update to the 787-powering Trent 1000, the Package C that is the baseline powerplant for the -9 version of the aircraft and also should deliver fuel burn improvements for 787-8s. The update has logged more than 60 hr. on the test stand already and been run up to 80,000-lb. thrust—the thrust setting will be 74,000 lb. Engine certification is planned in mid-2013, followed by first flight on a -8 in the second half of 2013 and later on the -9.
Deliveries, however, will begin with the -9 to. The first -8 with the Package C is likely around June 2014.
The Package C is meant to offer improved turbine engine temperature. The main changes involve the blading of the intermediate pressure compressor and the low-pressure tip control system using a semi-active approach, Carlisle says.
Almost all the Package A engines have been replaced with the Package B standard, delivering 1% specific fuel consumption improvements.
|777X Candidate vs 777 Incumbent|
|Fan diameter||132.5 in.||128 in.|
|Overall pressure ratio||62:1||40:1|
|Thrust||100,000-lb. class||115,000 lb.|
|Sources: Rolls-Royce, General Electric|