In Asia, as elsewhere, aerospace managers repeatedly stress airworthiness certification among the top challenges of moving into commercial aircraft production. As if to prove the point, Mitsubishi Aircraft has now twice skidded on the certification banana peel in its effort to develop Japan's first airliner since the 1960s, the MRJ regional jet.

The cause of the latest delay to the program has been dealt with, Mitsubishi Aircraft says, predicting only the usual challenges as the development effort moves toward its new first-delivery target, early 2017.

The reason for the timing of the company's delay announcement on Aug. 22—only months before the previously scheduled first flight—remains unclear, especially since the Mitsubishi Aircraft team has been working on the issue, obtaining permission to perform certification processes, since 2009 and completed it almost a year ago. The task evolved over time, says the company.

Despite the delay, the orderbook, for 165 aircraft, is not likely to suffer cancellations, says Yuko Fukuhara, the project's head of sales.

Mitsubishi Aircraft has begun making six MRJ airframes, five for flight-test aircraft and one for static ground testing. For the most advanced airframe, that of the first prototype, 90% of the parts have been made and fuselage sections are to be joined “in the near future,” says the company. Final assembly of the whole aircraft is due in the northern fall. The first Pratt & Whitney PW1217G engines will arrive in spring and first flight should now take place in the second quarter of 2015.

Major shareholder Mitsubishi Heavy Industries is building the airframe for the aircraft, which will have standard seating for 92 and 78 passengers in two versions.

The latest delay to the MRJ extends development to nine years from the originally planned five years, nine months. Its cause, not previously detailed, stems from 2009, Fukuhara told reporters in a conference call on Aug. 30. In that year Mitsubishi Aircraft learned that it needed company-wide organization delegation authorization (ODA), under which it would act on behalf of the certifying authority in the more routine aspects of approving designs and ensuring airworthiness standards. Mitsubishi Aircraft believes the MRJ program is the first to be fully covered by the ODA system.

And it underestimated the amount of effort involved in obtaining ODA from the Japan Civil Aviation Bureau, which locally instituted the FAA system to keep certification regulations internationally consistent. A key issue seems to be that achieving ODA is a once-only company effort. The company “was adopting the ODA-type system while our own program was also in development,” says a Mitsubishi Aircraft spokesman. “Therefore we had to handle both tasks at once.” Any later program by the company will rely on only updates to its ODA.

Still, it remains unclear why Mitsubishi Aircraft took until last month, more than five years after program launch and less than five months before its previous first-flight target, to announce that the ODA task, by then complete, had caused another delay of about 18 months. In 2009 Mitsubishi Aircraft delayed first delivery by about one quarter from the original target of late 2013 because of design changes. Last year it pushed the schedule out by an indefinite period—approximately a year and a half—because it discovered that it had not properly documented production processes for certification purposes. The ODA work was separate to that problem and ended in September 2012 when the authorization was received.

Delegation of aspects of certification work has a long history in aircraft certification, but the ODA system is more extensive than the traditional approach, demanding that a whole organization, not just certain individuals in it, show its competence and its procedural compliance. At the level of a type-certificate holder, such as Mitsubishi Aircraft, the organization must also ensure that its suppliers comply. Satisfied that the manufacturer can be trusted for routine activities, the government authority can devote more of its resources to high-level supervision.

Since the MRJ's ODA work is complete and the earlier problem of undocumented processes has been resolved, the program now has no hurdles except the usual challenges of moving through manufacturing to flight testing and certification, says Fukuhara.

Although Mitsubishi Aircraft appears not to have sought special assistance for its ODA work, Boeing has been an adviser to the program and the Japanese company has hired many foreign experts, especially former Boeing employees, to help it with such development challenges as relations with suppliers, ground tests, flight tests and certification.

Since MRJ development is now due to due to last so long, the program must be greatly exceeding its original budget. The increased cost of delays can be absorbed within the business case, however, says Fukuhara.

Employing engineers and facilities on the MRJ for more than one-and-one-half times the intended period is probably not the only source of a cost blowout. A manufacturer would normally have to compensate customers for late deliveries and, although Mitsubishi Aircraft will not comment on the issue, suppliers are typically entitled to compensation when certification is greatly delayed. The causes of the three delays do not appear to be the fault of any supplier.