The wide-cabin Gulfstream G650 is expected to obtain provisional certification by year-end, the Savannah, Ga.-based aircraft manufacturer said this week at the NBAA Convention in Las Vegas. According to Gulfstream, tests of the G650’s fly-by-wire system, engine inlet compatibility and operation in hot weather, among others, have recently been completed. As of last week, the four G650 flight-test aircraft had accumulated more than 2,077 hours on more than 626 flights. “On September 15, we had five G650 aircraft in the air at once,” said Gulfstream senior vice president of programs, engineering and test Pres Henne. “Four of the aircraft were conducting flight-test activities, while the fifth aircraft completed a post-production test flight. We are moving at a prudent pace toward our certification objective later this year.” Gulfstream has now flown four production aircraft in preparation for induction into final-phase manufacturing, where the aircraft are outfitted and painted. Fourteen aircraft are currently in the production process.