While the first Embraer Legacy 500 prototype continues to near the end of the production line, the midsize business jet will not make its maiden flight by year-end as originally scheduled. According to the Brazilian aircraft manufacturer, the delay stems from the Parker remote electronic unit software in the aircraft’s fly-by-wire (FBW) flight-control system.

Embraer president and CEO Frederico Curado revealed the problem earlier this month during the company’s third-quarter investor conference, describing the issue as “softness of flight control.” He also noted that Embraer is considering bringing this work in-house to resolve the software issue.

FBW applications on the $18.4 million jet include rudder, spoilers, elevators, flaps, ailerons and horizontal stabilizer, providing closed-loop control on all three axes and allowing maximum maneuvering capability in the aircraft’s normal flight envelope.

Yesterday here in Dubai, Embraer executive jet market and product strategy vice president Claudio Camelier confirmed that the Legacy 500 will not fly until the third quarter of next year due to the software problem. Certification of the aircraft will also slip to the second half of 2013, which is about a year later than the original plan, though the Brazilian aircraft manufacturer could possibly meet the jet’s projected 2013 service entry date.

To minimize the impact on the Legacy 500’s entry into service timeline, Embraer has reshuffled the schedule for ground testing. “We can still do a lot of things in ground testing to advance the Legacy 500 program,” Camelier said, while he added that ground testing is expected to begin on December 11.

The delays also have a domino effect on the Legacy 450, the 500’s smaller sibling, which now won’t be certified until late 2014 instead of late 2013. Entry into service for the Legacy 450 was originally planned for 2014, and this could very well still hold.