Gulfstream added a fifth G500 aircraft to the flight-test program, bringing the program closer to certification next year, the company announced on August 5. The aircraft, the first production test aircraft to fly with a full interior, took off from Savannah-Hilton Head International Airport, climbed to 48,000 feet, reached Mach 0.84 and flew for four hours, five minutes.

The aircraft will serve as the cabin testbed, enabling Gulfstream to check form, fit, function, noise, comfort and passenger interface. Testing will include the repetitive operations of all systems during the various phases of flight and during a range of missions. These include overnight trips, hot and cold weather flights and during turbulence. “The many hours of interior testing this aircraft will undergo, from galley and lavatory use to comfort and cabin health during long flights, help us hone every aspect of flying on the G500,” said Gulfstream president Mark Burns.

With the addition of the fifth aircraft to the program, the G500 fleet has flown more than 320 flights and accrued more than 1,300 hours. The fourth test aircraft recently made its first transatlantic flight and European debut at the 2016 Farnborough International Airshow.

The longest flight of a G500 lasted eight hours, 24 minutes. Gulfstream also has achieved a top speed of Mach 0.995 and altitude of 53,000 during G500 testing. Scheduled for certification next year and entry into service in 2018, the G500 is designed to fly 5,000 nm at Mach 0.85 or 3,800 nm at Mach 0.90.