Le Trent XWB couvre très probablement la gamme 777-200, 200ER et -300
Dans les pattes de l'A330-300 ...
Dernière édition par Admin le Mer 29 Oct 2014 - 16:08, édité 1 fois
She cited a range of about 7,900 miles, which is some 1,400 miles short of the range of the Airbus A350-900.
But she said Boeing estimates its lighter plane would be 12 percent cheaper to operate than the Airbus jet.
Airlines "will get incredible economics out of the (787)-10 if they don't need the range," Piasecki said.
Richard Aboulafia, an aviation analyst with Teal Group, is skeptical.
"These are highly theoretical numbers" based on assumptions about the plane's weight and aerodynamic characteristics, he said. "Everyone is eager to get a plane with these characteristics. Who wouldn't be? But it's a purely theoretical construct."
Aboulafia said the 787-10 economics Piasecki touted will depend heavily on engine makers delivering more powerful, yet efficient engines.
Another uncertainty is whether Boeing and its supplier partners can adjust their manufacturing systems and produce the plane on schedule.
The Dreamliner's global supply chain repeatedly ground to a halt in the past few years. Although it is now delivering better quality 787-8 sections to the final assembly site in Everett, it has yet to ramp up to a faster pace.
Boeing will "look at the reality of how the production system would handle it," Piasecki said. "There's lots of things we'd have to work on before we determine the timing."
Piasecki insisted the overlap with the 777 family is not an issue.
The 787-10 would be the same size as a 777-200ER. But the 777 has a much longer range, and she anticipates that plane would still sell to airlines that need to fly 8,900 miles.
The much larger 365-seat 777-300ER, Boeing's best-selling large airplane, is well-positioned in the market and won't be threatened by an Airbus rival until after 2015.
And if Airbus then produces, as expected, a version of the A350 that would be competitive with the 777-300ER, that's the airplane Boeing would revamp, likely with a new wing.
If the 787-10 moves from theory to reality, it will add to Boeing's already full plate.
Piasecki and Boeing Vice President Mike Bair talked of the possible launch of an all-new smaller jet family to replace the 737 and 757 single-aisle airplanes, to enter service around the end of this decade.
But if the 787-10 goes ahead, it would come first, she indicated.
Put it another way: Boeing may squeeze in the 787-10 after it finishes the 787-9, developing it concurrently with the 767 Air Force tanker.
The company would deliver the double-stretch 787-10 before the 737/757 replacement jet family, and follow that with the 777 enhancement with a new wing. All these projects are to be complete by around the end of this decade.
That's "a desirable, but theoretical, and extremely ambitious road map," Aboulafia said. "You have to wonder where the cash is going to come from."
Piasecki said the resources needed for a derivative airplane would not be so great, and Boeing would need only part of its Dreamliner design team to develop the 787-10.
FlightBlogger: A question about the payload range performance of the 787. At what point are you going to be able to deliver a 787 that flies fully 8,000nm, fully fueled and with full payload?
Jim Albaugh: Well right now if you look at the airplanes that we're going to deliver we meet the missions that our customers have put in place for us to meet. Now, I'll be the first to admit that we're not going to meet the spec, but I think we'll be able to meet what our guarantees are. And you got to remember, the first airplanes are going to be a little heavy, there are a lot of things that we're going to do to clean the airplane up, a lot of things to do with the engine manufacturers, and I feel pretty comfortable that over time we'll be able to get to the numbers that you just quoted. When that date's going to be, I can't tell you.
Boeing Commercial Airplanes CEO Jim Albaugh, for the first time, has acknowledged that the 787 will miss its intended performance specifications, though the majority composite jet will still meet the mission requirements of its customers.
"I'll be the first to admit that we're not going to meet the spec, but I think we'll be able to meet what our guarantees are," said Albaugh today at the International Society of Transport Aircraft Trading (ISTAT) conference in Scottsdale, Arizona.
Boeing's current spec calls for the aircraft to fly 14,200km to 15,200km (7,650nm to 8,200nm) range at maximum takeoff weight (MTOW) of 227,930kg (502,500lb) with 242 passengers in a three-class configuration.
Albaugh says "the first airplanes are going to be a little heavy" and the company has engine and airframe performance improvement packages to "clean the airplane up".
He adds: "I feel pretty comfortable that over time we'll be able to get to [14,800km (8,000nm) range]." However, adds Albaugh, "When that date's going to be, I can't tell you."
Originally designed to fly 14,200km to 15,200km with a maximum takeoff weight (MTOW) of 219,540kgs (484,000lbs), the MTOW has creeped up to 227,900kg (502,500lbs) in part to regain the aircraft's payload range performance, starting with Airplane 20.
Mike Bair, who currently heads Boeing's 737 advanced development effort, said in a recent interview that the 787 would achieve "high teens in terms of fuel burn" advantage over the 767 and "high single digits in terms of cash operating costs," but adds: "It would've been higher, but we decided to trade some of that currency for payload range, so to give the airlines an opportunity to work the revenue side of the equation."
Both 787 engine suppliers Rolls-Royce and General Electric are working on improvement packages for their respective engines. Rolls-Royce will introduce its 'Package B' model, expected to bring the Trent 1000 engine within 1% of originally planned specification, while GE is currently flight testing its Product Improvement Package (PIP1) on its 747-100 test bed.
The Rolls-Royce 'Package B' Trent 1000 includes a revisedsix-stage low pressure turbine (LPT) design, high-aspect-ratio blades, relocation of the intermediate-pressure (IP) compressor bleed offtake ports and a fan outlet guide vanes with improved aerodynamics. Boeing says the Package B configuration has not yet flown on any of the 787 test aircraft.
Further, industry officials suggest that Rolls-Royce is working on a 'Package C' engine intended to further improve engine performance on the larger 787-9.
GE says PIP1, which includes a revised low pressure turbine (LPT), will be test flown on ZA005 mid-year. The revision increases the blade, vane and nozzle count after a weight-saving reduction in these areas reduced performance. PIP1 is believed to bring the GEnx-1B engine within 1% of planned specification, say industry officials.
A second PIP2, which features aerodynamic improvements to the high pressure compressor (HPC), has been in ground testing since December and GE expects to flight test the changes in the second half of 2011.Certification of these changes is likely in the first quarter of 2012, followed by entry into service in late 2012, says GE.
Japan's All Nippon Airways anticipates taking delivery of the first 787 in the third quarter of 2011.
For the 787, program sources say ZA003 is conducting "build-up" testing in preparation for extended operations (ETOPS) and system functionality and reliability (F&R) testing. Early tests have focused on power cooling and single-engine operations.
It is in this same vein that we see Air Insight introduce its justification for a Next Generation 767, fitted with winglets, new engines, a KC-46A/787-style avionics and flight deck along with a new interior would provide a new commercial lease on life to Boeing's high margin jet and a product for airlines that don't need the 787-8's 7,755nm design range.
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.
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