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C919 Inches Toward Flight-Testing, ARJ21 Toward Upgrade
Comac, striving to fly the C919 by the end of 2015, is also planning an ARJ21 upgrade
Nov 3, 2014Bradley Perrett | Aviation Week & Space Technology
Comac, striving to fly the C919 by the end of 2015, is also planning an ARJ21 upgrade
Nov 3, 2014Bradley Perrett | Aviation Week & Space Technology
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The C919 nose will be fitted with a load-bearing windscreen frame.
With its first C919 flight-test aircraft now in final assembly, Comac plans to roll out the aircraft in less than one year and is trying to prepare it for a first flight in late 2015. Construction of the second flight-test aircraft is following about half a year behind the first.
For the 2014 Air Show China in Zhuhai Nov. 11-16, the C919 will appear again as a mock-up and models; but there is a good chance that one of its prototypes will overfly the 2016 show as China’s first production mainline airliner.
Comac has revised some of the specifications of the aircraft, which provided the launch airframe for the same CFM Leap 1 engine later chosen for the similarly sized AirbusA320neo. An extra row of six seats will be available in the C919’s high-density cabin arrangement, but the designed economic life has been shortened.
Bigger changes are in store for Comac’s earlier aircraft, the much delayed ARJ21 regional jet. The manufacturer now expects the ARJ21 will achieve airworthiness certification this year and adds that it is planning an update of the model.
Avic’s Xian factories are building C919 center fuselages and wing boxes. Credit: Comac Photo
Comac will not comment on its target for first delivery of the C919, however. In May, it said that would occur in 2018, 10 years after development was launched as a national program to advance the Chinese aeronautics industry.
Final assembly of the aircraft began on Sept. 19. As of mid-October, when Comac supplied photographs to Aviation Week from its new Shanghai factory, the C919 prototype’s forward and the Chengdu-built nose had been lowered into the assembly tool.
Delivery of the C919 fuselage sections from Comac’s structural suppliers, all subsidiaries of Avic, began in May. The last was the mid-aft fuselage, which, like the forward fuselage, was built by Avic’s Hongdu Aviation works at Nanchang. The center fuselage and center wingbox come from Avic’s Xian plant, which is also building the left and right wing.
“Final assembly is proceeding steadily,” says Comac, adding that it is trying to complete joining the structure by year-end, after which it will integrate the on-board systems. The roll-out is due in the third quarter of 2015.
Making a first flight around the end of next year is an ambition but seemingly not a definite expectation; the company says it is “striving” to do that. Considering that the first aircraft may not be rolled out until September, the timing looks tight. Mitsubishi Aircraft, which rolled out its first MRJ regional jet on Oct. 18, is allowing about half a year for ground tests before flying (AW&ST Oct. 27, p. 34).
The latest of several C919 schedule slippages, announced in May, seems to have amounted to only a few months. Just before that change in the plan, the first aircraft was due to be rolled out in June 2015 and fly four months later. When the program was launched in 2008, the first flight was scheduled for this year and first delivery in 2016, allowing eight years for development—which was generous by international standards but realistically so, considering the limited experience of the Chinese managers and engineers.
Comac will use six aircraft for flight testing, one more than originally planned. Parts for several of them are being made, the company says; the second aircraft is due to enter final assembly in the first half of next year.
Well aware that the major modules of early prototypes sometimes do not fit, Comac managers were a little nervous in awaiting delivery of the first C919’s major structural assemblies, program officials say. Asked whether mistakes have appeared in final assembly, Comac does not directly answer but says: “The problems of all fabrication methods have been resolved in the trial production phase” in the manufacturing of sample parts that began in 2009. “All parts being delivered have been passed by the Civil Aviation Administration of China [CAAC] and conform to the design requirements,” the company notes.
“For the manufacturing of C919 structural parts, Comac design and production staff and supplier production staff form technical, manufacturing and production teams. They collectively resolve production problems,” Comac adds.
In the U.S., CFM partners General Electric and Snecma began flight-testing the Leap engine on Oct. 6. The Leap 1A for Airbus and very similar 1C for Comac will be certified next year, says CFM. The C919 benefited from applying Leap 1A improvements to the earlier 1C, but the changes caused some of the delay in the Chinese program, a Comac official says.
A more recent change is an increase in maximum seating to 174 from 168 in an all-economy arrangement. Comac also says the aircraft’s designed economic life has been reduced to 80,000 flight hours from 90,000. Standard two-class seating for the C919 is 158.
The new factory, near Pudong International Airport, is “initially complete,” says Comac, apparently meaning that the plant is ready to begin work but is not fully equipped. By 2020, it will be able to build 150 C919s and 50 ARJ21 regional jets a year, the manufacturer says, declining to discuss its ramp-up plans.
Comac’s plant includes a final assembly hall in which a moving assembly line is “basically” installed. Another factory, though built for upstream work, is handling the final assembly of the first flying prototype, using automatic drilling and riveting equipment, an automatic system for aligning the modules, automatically guided vehicles and an aircraft movement system. “This is an automated assembly line of an advanced international standard,” says the manufacturer.
A composites factory is equipped with China’s largest autoclave, 5.5 meters (18 ft.) long, although Comac has decided not to use composites for large and difficult parts of the aircraft, such as the center wingbox.
Comac says customers have ordered 400 C919s. But the contracts have little binding effect, according to people who have seen some of them. And even if the order book comprised solid contracts, it would still have two shortcomings in the makeup of its customers. One is that they are all Chinese, with the exception of Gecas, which belongs to General Electric, a supplier. The impression, then, is that customers are ordering for national policy.
Then there is the curiously small quantity covered by the central government’s big three airlines—China Southern, Air China and China Eastern—to which the program must be looking as anchor customers. At the 2010 Zhuhai show, those three each ordered just five C919s, while Hainan Airlines, the private, fourth-ranked Chinese carrier, ordered 20.
Comac’s program was based on sales of 2,500 C919s. Even if only 1,000 are built, the big-three carriers will surely have to buy about 200 each. That assumes that the great bulk of C919 sales will be made in China—an increasingly realistic assumption, because the type has no clear path to endorsement of its airworthiness by the FAA or European Aviation Safety Agency (EASA), as originally intended.
But the C919 is being developed to international airworthiness standards, says Comac. At first it seemed obvious that the FAA could endorse the type certificate from the CAAC, since the U.S. authority was in the process of monitoring the ARJ21 program to assess its Chinese counterpart’s airworthiness competence. Unfortunately, it still is. The ARJ21 is running eight years late, so the CAAC’s work on the C919 has not been recognized by the FAA. EASA has never been involved.
So where does that leave the C919? “Getting an FAA or EASA certificate is still under discussion,” says Comac. This is not just important for international sales of the C919; Chinese customers also want a Western stamp on the type certificate.
Flight-testing will be conducted mainly from a new base at Dongying Shengli Airport in Shandong. Flight-test pilots and engineers also will be trained at the base, which Comac says will have “a delivery, maintenance and modification capability.” It will handle some ARJ21 flight-testing, as well.
Meanwhile, the ARJ21 is entering volume production. Comac said last month it had signed an order for 10 sets of airframe major assemblies with the Xian branch of Avic Aircraft. Xian builds the wing and fuselage sections for the aircraft.
Comac must now be fairly sure of the latest target, since it would not want to contract for volume production until it knew that the aircraft could be delivered according to the current design.
Under the shadow certification process, the FAA is expected to endorse the ARJ21’s CAAC type certificate, giving the ARJ21 regulatory acceptability in the markets of economically advanced countries. But after so many years of development, during which its technology has aged significantly, the type is unlikely to be a hot seller internationally. For example, its engine is the GE CF34-10, which Embraer is replacing on its next series of E Jets.
For an upgrade of the ARJ21, “we have already begun demonstration work and will fully go ahead after the type certificate has been issued,” Comac says. “This will mainly involve reductions in weight and drag. There will also be improvements in the avionics, flight controls and anti-icing system.”
The aircraft covered by the Avic Aircraft Xian contract will have serial numbers 120-129. Avic Aircraft is the large-airplane subsidiary of state aeronautics group Avic.
From this year, the factory is making many “technical quality improvements” in automatic riveting of fuselage panels, wingbox assembly, fuselage jigs and in detail assembly, says the branch company’s deputy general manager, Xu Chunlin. These and other measures, such as training, have greatly raised production stability and “have made an obvious improvement to product quality and production rate,” Xu is quoted as saying in Avic’s newspaper China Aviation News.
Earlier in the program, Comac was not satisfied with the quality of airframe modules supplied from Xian for flight-test aircraft. Around 2010, a problem was a bad fit between the center and outer wingboxes, says an industry official working on the program.
Comac endorses Xu’s statement that ARJ21 production quality has improved.
The Xian factory has everything ready for the increased rate, says Xu. The delivery dates for the 10 aircraft were not stated, but in the middle of this year Comac was planning to complete two ARJ21s in 2014, five in 2015, eight in 2016, 15 in 2017 and 20 in 2018. “The risk will be in going from eight to 15, especially since the C919 production preparations will be happening at the same time,” says the industry official.
Comac has been contractually obliged to compensate suppliers for the lateness of the program.
A version of this article appears in the November 3/10 issue of Aviation Week & Space Technology.
