Gulfstream Unveils New G700 Flagship At NBAA-BACE
Early last week, Gulfstream taxied out the first of four, or perhaps five, G700 flight-test aircraft in front of a carefully screened group of company employees, potential customers and vendors from one of its top-secret research and development hangars on the northside of its Savannah headquarters campus. First flight is imminent and customer deliveries are slated for 2022.
Aimed at toppling the 7,700-nm-range Bombardier Global 7500 as the reigning large-cabin uber jet, the $75 million G700 is the largest, heaviest, roomiest, most luxurious and, very likely, the longest-range business aircraft yet built by the U.S. manufacturer.
The G700’s advertised range is 7,500 nm, same as for the G650ER on which it is based. It shares the G650ER’s 6.3-ft.-high, 8.2-ft.-wide cabin cross-section, but it’s stretched 10 ft., to 56.9 ft., to make room for possibly a fourth, 8.75-ft.-long living area in the main cabin, along with extending the forward galley and making roomier the aft lavatory. (The Global 7500’s cabin is 54.4 ft. long.) Two additional wide-oval cabin windows are added to each side of the fuselage for a total of 20 transparencies flooding the interior with ambient light. Gulfstream claims it will offer the tallest, widest and longest cabin in business aviation.
As for the modest max-range estimate, Gulfstream is unlikely to deliver the G700 with 200 nm less range than its arch competitor from Canada. Industry observers expect final range numbers to be closer to 7,800 nm to 8,000 nm after flight tests are complete. Gulfstream officials also say the G700’s interior is bigger than that of the Global 7500, its cabin altitude is lower and its sound levels will be equal to, or lower than, 47.6 dB speech interference level at Mach 0.85 long-range cruise and 49 dB SIL at Mach 0.90 high-speed cruise. At the aircraft’s FL 450 mid-cruise flight level, cabin altitude will be 4,060 ft., and at its FL 510 certified max flight level, cabin altitude will be 4,850 ft. No other purpose-built business aircraft can boast a larger cabin, lower cabin altitude or so low an interior noise level.
Compared to the G650ER, the interior is being reconfigured for better space utilization upfront. Adapting the data concentration and power distribution network from the G500/G600 frees up more net usable cabin volume. So, the forward lavatory is being relocated from the left side, behind the main cabin door to a new right-side compartment just aft of the cockpit. Moving the lav makes room for a larger, left-side crew rest compartment with two wide-oval windows, plus a galley annex with stack ovens. In lieu of the crew rest compartment, some customers may instead wish to configure the space as a fifth living area, as shown in Gulfstream’s G700 full-scale sales mockup on display at Stand 606 at Henderson.
Depending upon choice of interior layout, the right-side galley has as much as 10 ft. of counter space, illuminated by two cabin windows. Galley cabinetry will offer close to 50% more storage volume than the G650’s split, left- and right-side galley sections. A comparatively large refrigerator is mounted under the work counter on the aft side. A second refrigerator is optional.
As shown in the mockup at Henderson, a typical cabin layout will feature a forward, four-chair club section; an entertainment section with 80-in., three-place divan facing a pop-up, 32-in. ultra-high-definition monitor in a credenza; a four-seat plus two-seat dining room; and a fully enclosed, aft master stateroom with 46-in.-wide bed flanked by an occasional-use bench seat. The aft lavatory optionally may be equipped with a shower.
Cabin chairs are being redesigned, offering customers a choice of foam densities and ergonomic features to make the seats more comfortable for individual passengers, as flights may last as long as 15 hr., or more.
The sidewall arm ledges are wider than in the G650, making room for individual storage compartments with 5-volt USB power outlets to charge personal electronic devices. There are no individual seat inflight entertainment monitors. Instead, telescoping docking stations pop up from the side ledges to hold tablet devices. Dedicated switches have been added to overhead passenger service units to control lights and to the arm ledges to control window shades and table lights. Cabin systems also can be controlled using a mobile app.
Similar to the Global 7500, the G700 will have a six-seat dining area with four chairs in a conference grouping and two facing chairs across the aisle. Interior designers are especially proud of the new pivoting, folding and extending table system in the six-seat dining area. It extends into a wall-to-wall dining table surface in less than 20 sec. without the need to install or remove and store an extension leaf.
The G700 retains the G650ER’s four Type IV over-wing emergency exits, thereby permitting a wide variety of cabin configurations, including flexible placement of bulkheads between seating areas, that fully comply with emergency exit access regulations. For instance, the main, four-section living area may be moved forward 52.5 in., one window frame length, to provide room for an extended aft lavatory with shower. Most competitive large-cabin business aircraft have a single emergency exit that restricts how cabins are configured.
The cabin wash light system is designed to harmonize with natural circadian rhythms. Using closely spaced white and amber LEDs, it automatically adjusts color temperature and brightness as a function of aircraft position to simulate dawn, daylight and dusk conditions. The illumination brightness between each of the cabin zones can be varied, as well.
Honeywell’s Jet ConneX Ka-band satcom will be a no-cost option and it should be popular. It provides up to 15 Mbps download speeds, supporting video streaming, high-speed internet access and, most importantly, Wi-Fi calling through passengers’ mobile phones.
Modified GVI Airframe With GVII Technologies
Gulfstream plans to seek type approval for the G700 as an amendment to the FAA T00015AT GVI type certificate, as it will retain most of the aerodynamics, structural properties and systems of the G650/G650ER. While the fuselage is stretched 10.1 ft., the wing, empennage and landing gear are virtually unchanged. New winglets will improve lift-to-drag performance and add 3.4 ft. to span. Subtle changes to the wet wing fuel cells will increase fuel capacity by 1,200 lb. Projected basic operating weight will increase from 54,500 lb. to 56,000 lb.
Two Rolls-Royce Pearl 700 turbofans, highly evolved Pearl-family variants of the G650’s BR700-725 powerplants, will each provide 18,250 lb. thrust with 3% to 5% better specific fuel consumption, reduced emissions with 35% margins to CAEP VI limits and lower than Stage 5 noise levels. The engine features a 51.8-in. blisk fan, nearly 2 in. larger than that of the BR725; a 10-stage compressor; a two-stage, shroudless high-pressure turbine; and a four-stage low-pressure turbine, one more stage than the BR725. The bypass ratio should be higher than 6.5:1 and overall pressure ratio is expected to exceed 50:1. The Pearl 700 fits inside virtually the same external nacelle contours and it uses most of the same aircraft interfaces, including bleed air, electrical and hydraulic systems.
Expect G700 systems to be adapted from the G650ER. It will use virtually the same 1,283-sq.-ft. wing, albeit with more advanced and more outboard canted winglets to reduce drag. Optimized for Mach 0.855 long-range cruise, the wing has 33 deg. of sweep at quarter chord, a supercritical airfoil and a modest aspect ratio just under 8:1. The longer fuselage provides more space between the trailing edge of the wing and the engine nacelles, a design characteristic likely to reduce interference drag.
Similar to the G650, the quad-redundant fly-by-wire system uses dual Thales Canada main flight control computers, plus a fifth FBW channel provided by a backup flight control computer. G650 pilots, though, will not be qualified to fly the G700 even though it shares many G650 systems. They’ll have to be GVII (G500/G600) type-rated because the G700 shares its Symmetry flight deck with its signature BAe Systems active sidesticks and touchscreen control units. Symmetry likely will be Gulfstream’s plan for future aircraft flight decks, making possible a common pilot type rating with differences training.
Symmetry is highly integrated with aircraft systems, slashing the length of checklists and allowing launch in 10 min. or less from battery power-up. Later this week, look for a G600 pilot report in ShowNews, providing insights into the G700 flight deck’s design.
Dual Collins HUDs are standard, along with a third-generation, high-resolution, cryogenically cooled InSb EVS camera. For now, Gulfstream is not changing over to a multispectral microbolometer EVS camera that can detect visible light as have Bombardier and Dassault with their latest technologies. But, similar to systems offered by Bombardier and Dassault, the G700’s HUD will display SVS and/or EVS imagery.
Gulfstream’s predictive landing performance feature will be standard. It looks at ground speed, flight path vector and touchdown point, runway condition, and manual or auto-brake performance to predict and display on both the PFD and HUD where the aircraft will stop on the available runway. As the aircraft approaches the threshold, the crew is advised, then alerted and finally warned, if the computer predicts the aircraft cannot be stopped on the pavement. If the crew presses their luck, a prominent red banner appears in the center of the PFD and an aural alert sounds “GO AROUND.” The go-around alert and warnings are recorded for later review by company flight operations.
Modest Performance Estimates
The G700’s preliminary maximum range is 7,500 nm at Mach 0.85 and 6,400 nm at Mach 0.90. With more-efficient Rolls-Royce Pearl 700 turbofans, new high-speed winglets and 1,200 lb. more fuel than the G650ER, actual range should be considerably greater, according to industry sources.
Similarly, Gulfstream conservatively projects sea-level, standard day takeoff field length to be 6,250 ft. In contrast, the G650ER requires 6,299 ft. of runway at MTOW at sea level and 11,139 ft. when departing Business & Commercial Aviation’s 5,000-ft. elevation, ISA+20C airport. The aircraft has a slightly better thrust-to-weight ratio than the G650ER but also a higher wing loading. The G700’s final runway performance numbers are likely to be better than those of the G650ER, in our opinion, mainly because of its newer technology engines.
Gulfstream primarily is positioning the G700 as luxury lifestyle air transportation for high-net-worth individuals and their families, as shown by the layout of the sales mockup. The four-section main cabin has sitting, entertainment, dining and stateroom areas, plus a fifth lounge area across from the galley.
The interior configuration, though, is modular. There are dozens of different layouts from which to choose. Corporate flight departments, for instance, might opt for three four-chair club sections and an aft stateroom with left- and right-side divans. Pairs of facing chairs and the twin divans would accommodate four passengers in lay-flat berths on overnight missions. Corporate operators are likely to insist upon fitting their aircraft with forward crew rest areas in place of the galley lounge.
Regardless of who buys the aircraft, it could shrink travel time between an impressive number of city pairs if Gulfstream ups the performance specs. That would enable it to fly from New York to Beijing, Tokyo, Muscat or Lucknow in 12.5 hr. at a higher cruise speed of Mach 0.87-0.88 rather than Mach 0.85. And a range of up to 8,000 nm would make possible nonstop Singapore to San Francisco, Paris to Perth or Miami to Mumbai, in around 15.5 hr. at a long-range cruise of Mach 0.85.
Many operators likely will fly the G700 on the same length missions as the G650ER. The extra $3.5 million buys nearly 25% more room in the main cabin, more standard features including Ka-band connectivity and a considerably more capable avionics suite. This is the most comfortable and capable Gulfstream yet announced.
Above all, Gulfstream intends the G700 to be the new leader in top-end business jets, offering longer range, a larger interior, lower cabin sound levels and better pressurization than anything built in Bordeaux or Montreal.
Stay tuned. This isn’t the end of this three-way race. It’s only a status report in late 2019. Expect Bombardier and Dassault to up their games in the coming months. The final outcome determining long-term winners and losers has yet to be decided.