If Pratt & Whitney executives felt discouraged by Mitsubishi Aircraft’s recent announcement that it would delay first flight and, likely, certification of the MRJ regional jet by a year-and-a-half, they didn’t show it last week after the airplane’s PW1217G geared turbofan flew for the first time on April 30 aboard Pratt’s Boeing 747SP test bed. In fact, the delay will not affect the PW1217G’s initial flight-test schedule, said next-generation product family v-p Bob Saia, as Pratt & Whitney continues to eye certification by early next year.
During the four-hour 40-minute first flight, the 15-person crew began the process of validating performance marks established during some 1,000 hours of ground testing with the program’s first four test articles. Over the next four to five weeks, Pratt & Whitney plans to conduct some 60 hours of flight testing on the engine, attached to a stub wing that protrudes from the upper front section of the 747SP’s fuselage.
Pratt & Whitney flew the 747 from its base at Montreal Mirabel, Canada, to Hartford, Connecticut’s Bradley International Airport for its annual “Media Day,” during which it hosted several reporters for a round of interviews and factory tours. Mitsubishi Aircraft executives who made the trip to Hartford last week expressed satisfaction with the PW1217G’s progress, and insisted that the delay to the MRJ program in no way involved the engine.
Rather, explained Mitsubishi Aircraft marketing director Yugo Fukuhara, the reasons center primarily on Mitsubishi Heavy Industries' failure to properly document engineering and production processes.
The program’s rather abrupt interruption came at the behest of the Japan Civil Aviation Bureau (JCAB), which, in concert with the U.S. Federal Aviation Administration (FAA) and the European Aviation Safety Agency (EASA), carries responsibility for issuing type and production certification for the airplane.
Since the JCAB intervened, Mitsubishi Heavy Industries (MHI) has had to remanufacture virtually all the parts for the first prototype, explained Fukuhara. The company has now begun refabricating the large structural components, most notably the forward part of the fuselage.
“Sometimes our workers improve fabrication processes to improve efficiency,” said Fukuhara. “But we didn’t update the documents. So some processes are different from [what appears in] the documents…We are almost completed with the [documentation] process.”
Second, said Fukuhara, the company needs to produce more documentation of the actual process of testing and analysis used for type certification compliance. “We didn’t think [we would need] so many documents, not only [related to] the technology itself, but also the processes,” he added. “It took a longer time than expected.”
The new program schedule calls for the first MRJ to fly some time during next year’s fourth quarter. As a result, the 92-seat MRJ90—the larger of a pair of models under development and the first scheduled for introduction—will not reach the market until the summer “or later half” of the 2015 Japanese fiscal year, which runs from April 1, 2015 to March 31, 2016.