COMAC C919

Le futur moyen-courrier chinois expose sa cabine depuis le 20 juin sur le stand de la COMAC (Commercial Aircraft Corporation of China).

Concurrent annoncé des Boeing 737 et Airbus A320, le nouvel appareil pourrait effectuer son premier vol en 2014 et serait mis en service mi-2016 selon son constructeur, mais ses prévisions semblent bien optimistes, au regard des déboires de l'ARJ-21.

Even before the latest certification difficulty, industry executives, watching Comac struggle with the ARJ21, had expected Comac to miss its first-flight and delivery targets.“They still have something to learn about project management,” says one Western engineer. Comac’s people are good at working out a solution in a particular area—say, hydraulics—but not nearly so good at balancing costs and benefits in one area against another. This is necessary, because it is the efficiency of the integrated aircraft that counts, not the stand-alone superiority of any particular aspect of it.

Another official says that, despite Comac’s ambition of breaking away from the bureaucratic tendencies of Avic, of which it is an offshoot, the commercial aircraft-maker’s engineers still show an alarming tendency to push decisions up the chain of command.

Comac announced in December it had completed the preliminary design review, the step before detail design. In fact, many issues—more than usual—remained to be determined, typically the placement of various items of equipment and the volume to be allocated to them. It may be that Comac always expected to have lots of loose ends after the preliminary design review but, regardless of that, they were certainly supposed to be tied up by March or April of this year. A few still remain to be resolved, delaying detail design.

A more recent question is whether to mount the thrust reverser on the pylon as well as the nacelle, taking a further step from the accepted integration of the CFM International Leap-X engine and the nacelle. The materials for the aircraft have not been chosen, but that is not necessarily a problem, because Comac has set a baseline design that one otherwise skeptical industry executive regards as mature. “They are doing well on the structure,” he says. It includes composite inner and outer wing-boxes. Additional advanced material may be worked into it later. The delay in beginning the detail design is not a wholly bad thing, says the same executive. The more time spent on the preliminary design, the less likelihood of foul-ups after the detail design has been completed, he notes.

A spokesman for Comac declined to comment on the certification process of the ARJ21 and schedule of the company’s two programs.

Comac announced “orders” for 100 C919s at the Zhuhai air show last November from airlines and other companies associated with the Chinese government or the program, but about half were actually options. Even the orders were not binding, say officials familiar with the contracts, which were signed mainly to save face at China’s premier air show.

The joint definition phase of the Commercial Aircraft Corporation of China (Comac) C919 narrowbody has been completed.

Together with the completion of the preliminary design, the manufacturer has now entered a "crucial point" in the detailed design phase, said Comac leaders at a C919 project meeting on 24 November.

They did not elaborate on the aircraft development progress, but said they plan to wrap up the detailed design phase in 2012 to ensure that the aircraft can conduct its first flight in 2014.

The leaders added that development work for the C919 went very smoothly this year.

Comac had previously said that it aims to have first metal cut for the C919 in December 2011.

Comac has in the last month received three major commitments for its aircraft, which is being developed in China as a possible competitor to the Airbus A320 and Boeing 737 family of aircraft.

The latest came from China's Bank of Communications Financial Leasing Co for an order of 30 of the aircraft on Tuesday. Sichuan Airlines signed a memorandum of understanding for 20 Comac C919s in October and Chinese leasing company ICBC Leasing had earlier inked an order for 45 of the same aircraft.

This takes the total order backlog to 195.

Detail design of the Comac C919 narrowbody airliner is going ahead without immediate participation by the Civil Aviation Administration of China (CAAC), which is declining to become involved until its certification processes win endorsement from the FAA, possibly late this year.

Comac's C919 narrowbody programme has passed a critical design review of its central wing system.
A
team of experts made the assessment on 17 January in Shanghai, after
studying the programme's design situation report, technology summary and
manufacturing solutions.
The experts accredited the central wing system and said that the next phase of work can now be carried out.
"The
assessment shows that the C919 has made some achievements, but it still
faces some challenges," says chief designer Wu Guanghui, while urging
his staff to carry on with work according to airworthiness standards.
The C919 programme is due to complete its detailed design in 2013, and start comprehensive manufacturing.
The twinjet is scheduled to have its first flight in 2014, with deliveries to follow in 2016.

The design of the center wing box of the Comac C919 narrowbody
aircraft has passed its critical design review, and managers of the
Chinese program have authorized the next stage in the composite
structural design.
Comac’s announcement on the critical design review did not mention the material that will be used for the center wing box.
It
has been designed as a composite structure mated to aluminum outer
wings, program officials have said. But the company also has prepared an
alternative plan for an aluminum center box.
In general, the
aircraft’s preferred structural system has used a mix of composite and
metal parts similar to that of the Airbus A380.
A committee
reviewed reports on the composite structural design this month, Comac
says. The group also looked at progress in making that structure and
approved further work.
The manufacturing program for the center wing box also was assessed.
The
C919 is due to make its first flight next year, although program
officials last year said this would be achieved only if there were no
delays.
Entry into service is scheduled for 2016.
Wu
Guanghui, Comac deputy general manager and C919 chief designer, told the
design review meeting that while the latest progress indicated a
certain degree of success for the program, challenges remain.