The Dassault Falcon 5X twinjet made its long awaited first flight from Dassault’s Bordeaux-Mérignac final assembly facility on July 5, using a “preliminary version” of the Safran Silvercrest engines.

According to Dassault, the preliminary flight-test campaign will last only a few weeks to help streamline the engine’s development process. Design issues have delayed the Silvercrest’s development for four years beyond Safran’s initial schedule.

Test pilots Philippe Deleume and Philippe Rebourg were at the controls for the two-hour flight.

The preliminary flight tests will permit Dassault to collect a certain amount of airframe and systems data that could not be generated during ground tests undertaken earlier this spring. The ground campaign included ground runs as well as low and high-speed taxi tests.

A full-fledged flight-test campaign with certifiable engines is scheduled to begin next year. Entry into service is expected in 2020.