Mitsubishi Aircraft has again extended the development schedule for its MRJ regional jet, this time by about one-and-a-half years, with first delivery now due in the second quarter of 2017, nine years after the program was launched.

First flight, previously scheduled for the last quarter of this year, will not now take place until the second quarter of 2015. The aircraft, powered by Pratt & Whitney PW1217G geared turbofans, will have standard seating for 92 and 78 passengers in two versions. Three customers have ordered 165 MRJs.

The company says it has “simultaneously addressed processes in which design and development of aircraft system and component specifications are aligned with safety certification. Design and respective certification, however, have taken greater resources than anticipated, which, in turn, impacted component deliveries and aircraft fabrication.”

The new schedule is aligned with delivery schedules agreed with suppliers.

When full-scale development of the MRJ began on April 1, 2008, first delivery was due in the fourth quarter of 2013. In 2009, the company made major design changes and slipped that target by one quarter. But a major delay was announced in April 2012, when the company moved the first-delivery target to an imprecise period, summer of 2015 to the first quarter of 2016.

The company says that, while the program has now proven that MRJ parts will be safe as manufactured, in its current work “all design and manufacturing processes must be clarified and documented, and safety ensured by following approved processes. Along with partners, Mitsubishi Aircraft needed to build out theses processes to validate component safety.”

Mitsubishi Heavy Industries has begun assembling at least two airframes, including the first flight-test aircraft.