Boeing 787 (partie 2)

With much of the test points already completed (90+% on the Trent 1000) Boeing is preparing for the final phase of flight tests. ZA004 will have its package “A” Trent 1000 engines switched out in favor of the improved package “B” engines starting on April 20th with the left engine. That process should be completed by April 30th followed by the right engine removal and replacement between May 2nd and May 11th. The aircraft should resume test flights soon after the remove and replace of the Trent 1000 engines though no new flight date has been revealed.

With two additional years to mature and improve its 787 powerplant, the manufacturer will introduce a host of improvements with its Trent 1000 "Package B" engines, which will be test flown later this year on Boeing's fourth 787 flight-test aircraft, ZA004, bringing the 62,000-75,000lb-rated (277-333kN) engines within 1% of specified specific fuel consumption.

Those planes await thousands of incomplete assembly jobs and
modifications necessary because of design changes since they were built.

Boeing has confirmed it has completed development and installation of revised 787 electrical systems software on its test fleet, modified after an electrical fire halted test operations last November, sliding the programme's schedule an additional six months.
Ground and flight testing of the final electrical software load - believed to be dubbed version 10.4C - first began in late February on test aircraft ZA003, say programme sources, and was rolled out to the balance of the Rolls-Royce Trent 1000-powered test fleet in March. ZA005 and ZA006, the General Electric GEnx-1B-powered test fleet, completed installation in late April.
Boeing said last week in its quarterly earnings call it is 95% through certification testing the Trent 1000 fleet and 75% through the GEnx-1B aircraft.
Prior to installation of the 10.4C electrical system software, Boeing's 787s were flying on an interim patched version that ensured power distribution in the event of a fault or arc like that seen during the November incident. That interim load allowed ZA004 to return to Boeing flight operations on 23 December 2010. The last of six 787s returned to flight with the interim load on 29 January.
On 9 November 2010, ZA002 suffered an electrical fire while on final approach to Laredo Airport, which caused a loss of power distribution throughout the aircraft, likely due to foreign object debris inside the P100 power distribution panel in the 787's aft electrical equipment bay.
The aircraft landed safely in Laredo, though Boeing halted all test operations for six weeks until an investigation could be conducted and an interim software and hardware solution developed to protect against FOD and the resulting faults.
The result of the six week slip in testing slid first delivery to Japan's All Nippon Airways from early 2011 to the third quarter.

With two and a half years to go before ZB021, the first production 787-9, is handed over to Air New Zealand at the end of 2013, Boeing is advancing forward on detailed design of the larger 250 to 290-seat Dreamliner, while it appears to be quietly laying the foundation for the third variant, the yet unlaunched 787-10.

Up Weight Paves The Way
First, Boeing has again increased the maximum take-off weight of the 787-9, though it's not entirely clear that the increase to 553,000lbs is driven entirely by regaining payload range capability due to an increase in airframe empty weight. Rather, one industry official indicates that the MTOW figure is be identical for the conceptual stretched 787-10. The increase actually appears to build a design bridge to the 787-10.

The same MTOW figures are indicative of structural similarity of the "simple stretch" -10, which hopes to fly 300 passengers a range of 6,900 to 7,000nm. If nothing else, the precedent for identical MTOW figures in Boeing stretches is found in the 777-200ER and 777-300, each with the basic takeoff roll weight capability of 582,000lbs.

While the 787-9 is starting to show signs of readiness for the -10, it still appears the larger jet is still "a long ways away" with hints of no earlier than 2015 and no later than 2017 starting to come in focus.

A Question Of Fuel
Quietly tucked into the changing MTOW of the 787-9 is a further 44gal reduction in the aircraft's fuel capacity. While not a very significant reduction when compared to the overall 33,384gal capacity, the amount now sits 144gal below the 787-8. This is a small figure, but 787-9 is set to deliver a 500nm range improvement over the -8 with more structure and payload flying on a wing with an identical wing planform as the -8. In a February 2010 interview, vice president of airplane programs, Pat Shanahan offered these thoughts on the optimized design flying farther on less fuel with more payload and structure:
That's beauty of engineering, we're not going to extend the length, add the same planform and decrease the range. So, the team, through understanding the performance of the -8, optimizing the configuration, they found a way to get the range and the extra payload.
The Cart Before The Horse
All this talk of the 787-9 and -10 is - first - entirely dependent on the 787-8 and its final certified configuration establishing a transparent baseline to work from. That final configuration, said Spirit AeroSystems CEO Jeff Turner in his company's earnings call last week, will make the process of designing for the -9 considerably easier:
I would say specific to the dash-9, as the dash-8 matures and nears certification, the dash-9 is a derivative off of that dash-8. So the more solid the dash-8 configuration is and becomes, the more straightforward the dash-9 derivative is. And that one is progressing very well.
Side-of-Body and Concept D
Before it was dismantled and relocated in pieces to the Boeing Boneyard in Everett, ZY997, the 787 static test airframe underwent a series of static tests with an updated side-of-body reinforcement modification designed for the larger -9 believed to be dubbed "Concept D". It is believed that Boeing is focusing particular attention on the side-of-body join, further refining this terribly troublesome area for both weight and further growth.


Fuselage Length & Program Cost
The phrase "simple stretch" tends to be a terrible misnomer, but is intended to convey the idea that an airframe's modifications are generally limited to the fuselage and leverage capabilities already built into the smaller model, rather than optimize the airframe for equal payload and range performance. The 787-9 is made up of two 10ft stretches of Sections 43 and 46, placing all the structural growth into the center fuselage which is integrated in Charleston, already equipped with tooling for second model.

Industry officials say that design of the -10 is slightly smaller today than it was in 2007, but may still require a stretch of not just the 43 and 46 sections, but the 47 as well. The 2007 design stretched Sections 41, 43, 46 and 47. As the program seeks a low-cost investment to take on the Airbus A330-300, capital costs for tooling will undoubtedly be an important factor in keeping the investment low, stretching as few sections as possible is central to this say company sources.

One potentially less obvious challenge is stretching the center fuselage so it still fits into the Dreamlifter. A 2008 diagram of the then-Global Aeronautica facility illustrated three types of centre fuselages on the pulse assembly line. Placing the full stretch in the center fuselage (preventing its air transport), could potentially make Charleston the base for the 787-10, saving tooling costs at Spirit and the nearby aft-fuselage fabrication facility.

According to sources, Boeing's latest schedule, thus far, has the 787 program starting F&R and ETOPs flight testing on June 9th. This information comes on the heels of ZA102 restarting flight tests after several months going through re-work and change incorporation at ATS Hangar 3 in Everett.

This aircraft flew a 50 minute check flight and landed back at Everett. No word yet on first delivery date but it is anticipated that ETOPs and F & R testing should take about a month followed by type certification for the Rolls Royce powered 787. Currently Boeing is 95% through the certification program for the Trent 1000 powered aircraft and 75% complete on the GEnx-1B powered version of the 787. Delivery of the first GE powered 787 to Japan Airlines is expected about a month or so after delivery of the first 787 to ANA.