The first Mitsubishi MRJ flight-test aircraft started flight tests in the U.S. on Monday, taking off from Grant County International Airport in Moses Lake, Washington, at 1:20 p.m. local time. The airplane flew for three hours and 18 minutes, returning to Moses Lake at 4:38 p.m., Mitsubishi reported. The company reported no anomalies during the flight.

The airplane first arrived in Moses Lake from Japan on September 29, following a three-day ferry mission that included stops in Hokkaido, Russia’s far east and Alaska. The trip marked Mitsubishi’s third attempt to fly to the U.S. after two failed attempts on August 27 and 28, both aborted when it detected anomalies in the signals generated by sensors monitoring the airplane’s air management systems. It has since replaced the faulty sensors and completed inspections to ensure the problem does not recur.

Nevertheless, early this month Mitsubishi confirmed reports out of Japan that it has communicated with MRJ launch customer All Nippon Airways about another possible delay in first deliveries due to “technical reasons.” If the manufacturer fails to deliver the first airplane by mid-2018, it would mark the fifth major delay for the troubled program.

In a written statement to AIN, Mitsubishi Aircraft insisted that it has not definitively told ANA that a delay will occur, however.

Mitsubishi has established a new engineering facility in Moses Lake from which to base flight testing of the first four prototypes. FTA-3 took its first flight in Japan on September 25. The company plans to use a total of five flight-test articles, the fourth of which it expects to fly this year.