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da i_disa » 11 gennaio 2012, 8:50
Boeing eyes 787 improvements along with production ramp up
11 gennaio da aspireaviation
It is hardly a surprise when Chicago-based airframer Boeing missed its 2011 delivery targets on the beleaguered 787 Dreamliner and 747-8 programmes, after delivering a combined 12, consisting of 9 Boeing 747-8F freighters and 3 787 Dreamliners, against the original target of 15 to 20 aircraft envisioned, including 5-7 787 deliveries, in October when the company announced its strong third-quarter profit of US$1.1 billion (“Boeing posts stellar 2011 third-quarter profit amid 787 & 747-8 concerns“, 1st Nov, 11).
Indeed, the persistent downward revision in the number of 787 and 747-8 deliveries by the world’s second-largest aircraft manufacturer throughout the year highlighted the challenges posed by a significant amount of rework required to bring the early-built 787 production examples to US Federal Aviation Administration (FAA) FAR Part 25 certification standard.
Boeing revised the number of 787 and 747-8 deliveries earmarked for 2011 from 25-40 examples to 25-30 in late July 2011 and then further reduced that number to 15-20 in late October, with two-third of the deliveries weighted towards the revamped jumbo jet freighter. It turned out that Boeing managed to deliver only 9 of the newest freighter, an upgraded version from the iconic 747 jumbo jet with a new wing design, new engines and improved aerodynamics, against the planned deliveries of 12 examples.
“We just could not get all the work done on those airplanes to get them out the door by the end of the year,” Boeing Commercial Airplanes (BCA) vice president (VP) of marketing Randy Tinseth told Bloomberg.
The third 787 delivered to Japan’s largest airline by passenger traffic, line number (LN) 31 which carries the registration number JA805A and is the first 787-8 equipped with the improved Rolls-Royce Trent 1000 Package B engines that feature a revised six-stage low pressure turbine (LPT) and outlet guide vanes (OGVs) with better aerodynamics aimed at bringing its engine specific fuel consumption (SFC) to within 1% of its original target, along with its siblings JA807A and JA804A, LN41 and LN9, respectively, were meant to be delivered in November 2011. As of this writing, the two aircraft are going to be delivered in the first half of January, flightglobal reported.
As a result of the delay, which was caused by the need to re-wire the wiring installation on the aircraft to meet the FAA certification standards as well as the non-recurring failure of the power-up of the auxiliary power units (APUs) prompting replacements from the component supplier Hamilton Sundstrand, ANA postponed the commencement of 787 flights from Tokyo Haneda to Beijing by a month from December to 14th January.
Meanwhile, the pre-requisite for Boeing to start delivering 787s equipped with Block 4 General Electric GEnx-1B engines, the completion of functions and reliability (F&R) tests on board production standard examples required under the US Federal Aviation Administration (FAA) FAR Part 25 certification have yet to begun, with LN35 earmarked for the task only beginning F&R and extended twin-engine operations (ETOPS) test flights in mid-January. This was delayed from late-2011 with Aspire Aviation‘s sources at the world’s second-largest aircraft manufacturer indicating the first Air India 787 to be delivered, LN35, had been included in the original 787 delivery target. Japan Airlines (JAL) now eyes its first 787 delivery in mid-February, whereas Air India says it expects its first 787 to be delivered in late January, a prospect widely considered unlikely to be met.
Production improvements, 787-9 parts in focus
While Boeing’s road to ramping up the 787 production rate to its target of 10 airplanes per month by the end of 2013 will unquestionably be the most scrutinised development on the perennially delayed aircraft in 2012, as it ramps up the 787 production from a current rate of 2.5 airplanes per month to 3.5 per month by April before ramping up to 5 units per month by the end of this year, Boeing looks to improve the 787 production system by incrementally reducing the amount of rework on each new 787 entering into production as well as reducing the 787′s weight in an effort to recover some of the performance shortfall resulted from an overweight issue and higher than originally targeted engine specific fuel consumption (SFC).
For instance, Boeing is eyeing line number (LN) 63 as the first 787 production example with no rework required, a flightglobal report said. The LN51 Boeing 787 is now completing its final assembly and Boeing has received parts for up to airplane LN56, according to flightglobal and Aviation Week reports.
Moreover, according to Aspire Aviation‘s multiple sources at the Chicago-based airframer, Boeing plans to feature more composite contents on the 787′s wings and airframe structures in an effort to trim weight starting on airplane LN90, the block point for weight reductions which will enable LN90 to become the first airplane meeting the 787-8′s original target of manufacturer’s empty weight (MEW) and airline-specific operating empty weight (OEW).
The first 787 prototype, ZA001, decommissioned by the company last year which a flightglobal report characterised as the world’s most expensive test aircraft with an estimated cost exceeding US$4 billion, is 9.8 tonnes (21,500 lbs) overweight, whereas LN7 to LN19 are 6.1 tonnes (13,500 lbs) overweight and LN20, featuring an increased maximum take-off weight (MTOW) of 227,930 kg (502,500 lbs) from 219,539 kg (484,000 lbs), are around 4 tonnes (8,800 lbs) overweight (“Challenges remain as Boeing 787 becomes reality“, 3rd Oct, 11).
Other block points for further weight reductions include LN34 for China Southern Airlines and LN50 for Ethiopian Airlines.
“We will continue incorporating improvements into the production system – referred to as blockpoints. Each blockpoint will further reduce production costs and weight on the airplane,” Boeing spokesman Scott Lefeber said.
A key determining factor in achieving the goal of meeting the original manufacturer’s empty weight (MEW) and airlines’ operating empty weight (OEW) targets of the 787-8, these sources say, is the availability of redesigned 787-9 parts which are much lighter than those designed for the 787-8, a variant considered by one of the sources as “over-engineered”.
Suppliers have begun the early production of ZB001, or LN139, the first 787-9 production example to be produced last November and include many significantly lighter parts such as Spirit AeroSystems’ one-piece cockpit window frame that will eliminate around 200 fasteners and reduce the cockpit structure’s weight by 100 lbs, a flightglobal report said.
These sources caution, however, Boeing must have to balance between the planned production ramp-up and the availability of 787-9 parts, which is gradually becoming more abundant towards the end of 2012 well, or otherwise LN90 may not be able to meet its original weight targets by then.
With the 787 production system producing 3.5 airplanes per month through a large part of 2012, coupled with the fact that LN51 is now completing its final assembly, Boeing’s goal of meeting the manufacturer’s empty weight (MEW) and operating empty weight (OEW) targets seems achievable at this point.
Meanwhile, Boeing plans an even more significant improvement on the 787-9 over the baseline -8 variant, with Aspire Aviation‘s multiple sources confirming Boeing has completely redesigned the side-of-body structure, thereby eliminating the side-of-body modification prompted by the discovery of a delamination issue during an ultimate load test in 2009 that bent the wing to 150% of its normal engineering loads experienced by a typical flight.
The side-of-body modification which involves installing two titanium fittings, one on the upper and the other on the lower side of each 787 wing and held together by numerous fasteners, these sources say, not only weighs some 363 kg (800 lbs), but is also expensive to install with a significant amount of labour time required.
“The design on the side-of-body modification is proprietary,” Boeing spokesman Scott Lefeber said.
The elimination of the side-of-body modification on the 787-9, coupled with other redesigned parts, are meant to remove a considerable amount of additional fasteners caused by design changes that contributed to the aforementioned overweight issues, which enables Boeing to recover some of the ground lost on payload/range capabilities, including the higher than targeted engine specific fuel consumption (SFC).
The Rolls-Royce Trent 1000 Package A engine, rated at 64,000 lbs of thrust, has missed its original specific fuel consumption (SFC) target by 2%-4%, whereas the Package B engine, rated at 70,000 lbs, will bring the SFC to within 1% of its original specification. Rolls-Royce plans a Package C engine rated at more than 74,000 lbs of thrust powering the 787-9.
Likewise, the General Electric GEnx-1B engine missed its original specific fuel consumption (SFC) by 2.4%, though the performance improvement package PIP 1 and PIP 2 will deliver a combined SFC reduction of 2.9% with PIP 1 contributing a 1.4% improvement while PIP 2 contributing the remainder, thus making the General Electric engine slightly better than its original specification.
In addition, Aspire Aviation‘s sources say the flight tests on the hybrid laminar flow control (HLFC) system aimed at reducing the drag by 2%, carried out by the third flight test airplane ZA003, have shown a “generally better-than-anticipated drag reduction”.
“We aren’t going to go into specific details on the HLFC testing or the results, but we are happy with the results we are seeing. We don’t comment on our design changes as they are considered proprietary [and] we continue to work our weight reduction plans aggressively, with our current estimates indicating we still have some work to do to get where we need to be,” Boeing spokesman Scott Lefeber commented.
In the meantime, Boeing contended that the estimation of the 787′s patented one-piece contoured barrel (OPCB) on the elimination of 1,500 aluminium sheets and 40,000-50,000 fasteners remains accurate despite the heavy rework and significant amount of design changes on early-built 787 examples.
“These figures were calculated when the 787 programme was first launched and remain accurate estimates today. Also just to clarify, the fastener reduction applies to one barrel section, not an entire airplane. So in general terms, a one-piece barrel uses approximately 40,000-50,000 fewer fasteners compared to an aluminium airplane,” Boeing spokesman Scott Lefeber explained.
Boeing has adopted a one-piece composite barrel approach for the 787 whereas Airbus opted for the panel approach for the A350 XWB, with 4 composite panels attached to a composite frame. European plane-maker Airbus claims the composite frame with a metal floor grid creates a natural electrical structural network (ESN), the thickness of different composite panels located at different areas of the fuselage could be customised to local engineering loads as well as allowing an easier maintenance process by removing and replacing the damaged composite panel. Boeing countered that its composite barrel approach on the 787 Dreamliner saves the weight of the metal frame and the fasteners used to attach the four composite panels onto the frame while meshing a long and thin copper wire to create a conductive path in the event of lightning strikes into the composite barrel. Boeing also said the different thickness of the composite barrel could be achieved in the lay-up process and cited the US FAA-approved “patch pair”, installing titanium patch panels on the damaged surface while refilling composite material could be procured in the longer-term, coupled with a fewer amount of fasteners, will lower the 787′s maintenance cost against its mid-sized arch-rival.
Image Courtesy of Getty Images
Boeing’s widebody product strategy
2012 is destined to be a crucial year for the Boeing 787 Dreamliner in demonstrating whether the revolutionary aircraft has made a turnaround and whether the pendulum has started to swing in a different direction after a bumpy ride on the aircraft programme that led to a US$18 billion of gross inventory and US$9.7 billion of deferred production cost, figures that will be updated when the US aerospace giant releases its 2011 full-year financial results on 25th January.
Indeed, the aircraft programme, which Boeing Commercial Airplanes (BCA) vice president (VP) and general manager (GM) of airplane programmes Pat Shanahan characterised as “a hell of a ride” in a CNBC documentary on the 787 Dreamliner, faces its next biggest challenge in the ambitious production ramp-up to 10 airplanes per month laid out by the latest Z24 schedule, which specify 45, 66 and 119 787 deliveries in 2012, 2013 and 2014, respectively.
Notwithstanding this, the year of 2012 may see Boeing shedding more lights and providing more clarity on its widebody product strategy, especially over the developments of the double-stretched 787-10X and 777X.
In a first sign of development, Aspire Aviation can exclusively reveal that Boeing has issued a request for proposal (RFP) to General Electric (GE) and Rolls-Royce (RR), with one of Aspire Aviation‘s sources saying Pratt & Whitney (P&W) is possibly included in the RFP, for a 100,000 lbs engine powering the 777-8X and -9X, the conceptual replacement aircraft for the ultra long-range 777-200LR and the highly popular 777-300ER, respectively.
The new GE9X engine, which will have a smaller fan diameter of 325 cm (128 inches) and a lower thrust of 99,500 lbs, is expected to deliver a 10% lower engine specific fuel consumption (SFC), when combined with a 787-styled carbon fibre wing, will deliver a 15% lower block fuel burn per seat, according to a flightglobal report.
Aspire Aviation‘s multiple sources previously indicated that the GE9X, which will incorporate the twin-annular pre-mixing swirler II (TAPS II) technology found on the GEnx engine and deliver a 10% lower engine SFC, coupled with the “internal stretching” that removes internal frames in some sections of the 777-9X’s fuselage which will increase the capacity of the 365-seat 777-300ER to 380 and 390 seats without major costly modifications, will contribute a 5% reduction in the aircraft’s block fuel consumption alone. Coupled with the 787-styled composite wing and possibly the application of Alcoa’s 3rd-generation aluminium-lithium (Al-Li) technology on the 777-9X’s fuselage, which the world’s largest aluminium producer says offers a 12% better fuel efficiency with a 10% weight saving and a 6% reduction in skin friction drag, the 777X is likely to strengthen Boeing’s leadership position in the 350-400 seat market segment (“New Boeing 777X likely to be a highly efficient derivative“, 14th Sep, 11).
As a 320-seat 787-10X aircraft with a range of 6,800 nautical miles (nm) complements the Boeing product line in the widebody arena, Aspire Aviation believes Boeing will eventually launch both aircraft derivative programmes, with Aspire Aviation‘s sources indicating a 2012 launch of the 787-10X for a 2018 entry into service (EIS) whereas the 777X is likely to be launched in 2013 with a 2019 EIS. Nevertheless the sources caution that the launch and EIS dates of these aircraft are fluid, pointing out that Boeing could launch the 787-10X as late as 2014 yet target an entry into service (EIS) of 2016, owing to the minimal amount of work involved in developing the -10X variant.
In particular, the Boeing 787-10X will burn 20% less fuel than an Airbus A330-300 with a 10% and 5% lower operating cost than the A350-900 and -1000, respectively, while requiring minimal investment and engineering resources since the foundation of further stretching the 787 fuselage has already been laid by the -9 stretch variant. In launching the 787-10X, Boeing will offer a competitive A330-300 replacement with more range in the medium to long-haul marketplace.
On the sales front, the 787 is likely to see more new 787 orders in 2012 as the aircraft programme continues to retire risks steadily and a 787-10X launch could give the 787 programme further sales momentum, should the double-stretched variant be launched this year.
“Boeing also booked a positive net 13 orders for the 787. Considering the delays on the programme, we view this as a positive. We continue to believe there is substantial pent-up demand for the 787 that will start to translate into orders once the company is able to demonstrate some consistency to its delivery schedule,” analysts at Wedbush Securities said in a January 6th research note to clients.
“We continue to believe the 787 deliveries will be uneven through most of 2012, but the focus for investors is the 787 production ramp. We continue to believe that the step up to 3.5 per month in April should not be an issue, but the step up to 5 expected in Q4 12 is the primary challenge for Boeing and its supply chain. For 787 deliveries, the company attributes the delays to both customer issues and one-time items, and does not believe there are any systemic issues. If this is true, we would expect to see a gradual increase in 787 delivers in 2012, where we currently model approximately 55 787 deliveries,” the Los Angeles-based investment bank said.
Last but not least, while the Boeing 787 Dreamliner continues to face significant challenges in its ambitious production ramp-up plan, there should be exiting times ahead as the 787 will eventually prove itself as a good aircraft with the ongoing weight reduction programme and other continuous improvements; from an investor’s perspective, the Boeing 787 Dreamliner will hopefully become a profit-maker that Boeing officials and the Wall Street (once) hoped for, which then comes down to Boeing’s ability of executing its plan on the 787 programme smoothly with a not-so-perfect track record that earned every stakeholder’s serious black eye in the past as well as in the foreseeable future.
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