The first Gulfstream G500 test aircraft has completed a 50-flight battery of flutter tests, clearing the programme to proceed to more advanced flight envelope testing.
All three flying prototypes have logged more than 430 flight hours on over 105 flights, Gulfstream says.
The programme is now roughly one-third of the way through a nearly 2.5-year campaign to receive airworthiness certification by the end of 2017, with deliveries of the long-range, large-cabin jet beginning in 2018.
The second test vehicle, meanwhile, has completed climatic chamber trials at the McKinley Climatic Laboratory at Eglin Air Force Base, Florida.
The aircraft was exposed to temperatures ranging from -40˚C to 55˚C over five days.
A fourth flight-test aircraft has also emerged from Gulfstream’s Savannah, Georgia production facility and entered final preparations before beginning airborne evaluations, Gulfstream says.