On August 29, Gulfstream added a fifth test aircraft to the G600 fleet, a production aircraft outfitted with a complete interior. On its first flight it flew for nearly three hours, reaching 51,000 feet and a speed of Mach 0.85. Gulfstream intends to conduct repeated operations of all cabin systems to evaluate comfort, noise, functionality, ergonomics, passenger interaction and appliance reliability.

“The goal of including a production aircraft in our flight-test program is to ensure we deliver the most functional, comfortable and reliable cabin environment to our customers,” said Gulfstream president Mark Burns. The five G600 test aircraft had logged 790 hours during 180 flights through August 29, the longest lasting 13 hours and 5 minutes in May. Development testing has been completed in initial envelope expansion and flying qualities, brakes, low speed or stall, load calibration, parameter identification and climb performance. Company testing continues and certification testing for loads and flutter has been completed. The aircraft has reached a maximum speed of of Mach 0.995 and an altitude of 54,000 feet. Gulfstream says the G600 program is on schedule for certification and deliveries next year.

Through August 20 the five G500s had flown 3,460 hours during 905 flights; the G500 recently completed certification testing for flyover noise, cabin systems, brakes and lighting, and company testing of the fuel system is finished. The aircraft made a 10-hour, 6-minute flight in April and set a city-pair record from Savannah to Paris in May, covering the 3,788 nm in 7:40 at an average speed of Mach 0.90. The G500 has been flown at Mach 0.995 and at 53,000 feet. Certification flying is expected to be completed in the fourth quarter.

Both the G500 and the G600 are powered by Pratt & Whitney Canada PW800-series engines and have Symmetry flight decks with Honeywell Primus Epic avionics and cockpit sidesticks linked to full fly-by-wire flight controls. The 16,000-pound-thrust class PW814GA and PW815GA powerplants have the same core technology used in the company’s geared turbofan airliner engines. They have a 10,000-hour time-between-overhaul limit (TBO) and no midlife-inspection requirement. According to Gulfstream, the new engines are 30 percent more efficient than those on the G450 and help extend the time between key maintenance on the new aircraft by up to 25 percent. The aircraft will be offered with the optional Jet Connex Ka-band satcom using the Inmarsat service for high speed Wi-Fi, real-time television, audio and video streaming worldwide on both new large-cabin aircraft and as a retrofit option. Jet Connex, which provides coverage everywhere except over the polar regions, is FAA and EASA certified. The hardware is supplied by Honeywell.

G450/G500 Replacements

Gulfstream formally launched the two large-cabin designs in October 2014 to replace the G450 and G550. The top speed for both the G500 amd G600 is Mach 0.925, the same as for the G650ER ultra-long-range flagship. The G500 and G600 incorporate a new high-speed wing with 36 degrees of sweep. The G600 wing is eight feet longer than the G500’s, allowing the aircraft to hold 10,000 pounds more fuel. Possible nonstop city pairs for the G500: Istanbul to Cape Town, South Africa; Los Angeles to London; and San Francisco to Tokyo. The aircraft has a range of 5,000 nm at Mach 0.85 and 3,800 nm at Mach 0.90. The G600 has a range of 6,200 nm at Mach 0.85 and 4,800 nm at Mach 0.90. (Eight passengers.)

Gulfstream has set initial prices at $44.5 million for the G500 and $55.5 million for the G600. The Savannah production line that the company built for these aircraft promises to allow for more efficiencies than the flagship G650 offers; that aircraft already uses 80 percent fewer fasteners and 50 percent fewer parts than the G450/G550.

Both aircraft provide a cabin altitude of 4,850 feet at 51,000 feet and 100-percent fresh air. The aircraft feature the same large oval windows that are on the G650, with dimming provided by a dual roller-shade system. The cabin noise level for both new models is expected to be less than 50 dBA. The latching mechanisms for the cabinetry are also quieter than on earlier models.

The cabin cross-section of each aircraft measures 95 inches wide and 76 inches tall—about seven inches wider and two inches taller than cabins in the G450 and G550—and they can be configured for up to 19 passengers. The aircraft also feature a new passenger single-seat design with all seat controls located on the inboard armrests and pockets sculpted into the interior arms for more hip room. The aircraft borrow some architecture from the Elite interiors developed for the G650, such as the high-tech display of galley and inflight entertainment equipment.

The G500 has three living areas and the G600 has up to four as well as an optional crew rest area. Both aircraft offer forward and aft lavatories, plus a full-size galley that can be located either forward or aft. The flexible galleys allow a high degree of customization and have a four-cu-ft refrigerator, a microwave/convection oven, an optional steam oven and an oversized sink. The baggage compartment is accessible in flight through the aft lavatory and has additional floor and ceiling tracking to allow for flexible loading. It incorporates fold-down shelving and space that can be configured to store golf clubs, ski gear or large suitcases.