Gulfstream Aerospace this week is unveiling the first full production example of its new G500 large-cabin business jet, featuring an all-new cabin interior. The aircraft’s appearance here in Orlando for the NBAA show comes as the manufacturer prepares to begin the final certification phase of flight testing in early January en route to FAA and EASA approval in 2017, followed by service entry, ahead of schedule, later that year.

Also on display at the NBAA event is a new cabin mockup for the larger G600 model, which is expected to make its first flight, ahead of schedule, during the remaining weeks of 2016. With a high degree of commonality between the two new long-range jets, the G600 is expected to enter service in 2018.

The G500 featured on the NBAA static display became the fifth example (designated P1) of the new model to join the flight test program on August 5. Its role will be to validate the interior design of a production-grade cabin, focusing on the form, fit and function of fittings and furniture, as well as factors such as noise, comfort and passenger interface. Missions flown include cold and hot weather operations, as well as overnight flights, turbulence and durability testing.

Serial production of the G500 is now underway at Gulfstream’s expanded production facilities in Savannah, Georgia. A flight simulator for the new model is already in use at the FlightSafety International training facility in the same city.

Gulfstream’s very substantial investment in laboratory testing over the seven years the G500 and G600 have been in development appears to be paying off in terms of both aircraft maturity and rapid progress with the certification process. “We’re hitting operational inflight reliability numbers already,” said flight test vice president Lawrence Buerger. “Almost every flight we’re doing now is completely squawk-free.” This has contributed to rapid progress with flight-testing as aircraft can be quickly turned around between missions.

As of early October, Gulfstream had completed almost 55,000 hours of ground testing using the systems integration bench, the integration test facility (ITF) and the iron bird unit. The final stages of interior design have been tweaked based on work using the cabin integration test facility. At the same time FAA and EASA officials have been involved in human factors testing in the ITF and in a FlightSafety simulator.

By involving FAA at an early stage in the test process, Gulfstream managed to earn some certification credits during the initial phases of flight-testing, which involves four prototypes in addition to the first production standard example. This was achieved by establishing that some key aspects of the systems integration process had been validated ahead of the final certification flight tests, and the credits cover factors such as crew workload. “FAA told us that they consider Gulfstream to be the gold standard in how integration work gets done,” commented Dan Nale, senior vice president for programs, engineering and test.

With an eye to smooth entry into service and delivering on promises for a high degree of reliability and availability, Gulfstream involved its product support teams from the early stages of the G500/600 development program to hold their engineering colleagues accountable in this respect. The manufacturer has employed advanced virtual and augmented reality tools in its Immersive CAVE laboratory to work on aspects of design such as ensuring that all parts can be readily accessed by mechanics. It also has developed standardized tooling for maintenance tasks and has established specific goals for how much time it should take to install and replace components.

Existing Gulfstream operators and prospective customers also have had a very direct say in how the new jets have taken shape through the Advanced Technology Customer Advisory Team. Their input is particularly apparent in the cockpit and cabin of the new aircraft (see story 512G500Cabin on this page).

Improved Performance

Through a combination of a new aerodynamic design and Pratt & Whitney Canada’s PurePower engine technology, Gulfstream believes it will be delivering market-leading high-speed range capability, as well as reduced operating costs and a reduced environmental footprint. The G500 is powered by the 15,144-pound-thrust PW814GA turbofan and the G600 by the 15,680-pound-thrust PW815GA—both featuring a wide-chord integrally bladed fan, composite nacelle, dual channel Fadec controls and a new thrust reverser.

Maximum speed is projected at Mach 0.925. The G500 will be able to fly 5,000 nm at Mach 0.85, or 3,800 nm at Mach 0.90. The G600 has longer legs still, with 6,200 nm of range at Mach 0.85 and 4,800 nm at Mach 0.90.

“Flying at Mach 0.90 we can save operators and their passengers around 50 hours of travel time per year, because they will be spending less time on the aircraft,” stated Gulfstream vice president for advanced aircraft programs Mark Kohler. This assumption is based on a comparison with the typical Mach 0.80 speed for the existing G450 and G550 model, and also on the typical operational patterns seen with operators of the company’s current long-range flagship, the G650, which has similar high-speed capability.

According to Gulfstream, higher speeds also translate into maintenance savings for operators. “The faster you go, the less these aircraft will cost you to maintain,” said Kohler. “The harder you work the engines, you get better value because you are working those engines for a shorter period of time.”

New Cockpit

To the anticipated delight of pilots, much of the fly-by-wire G500/600 magic is found in the cockpit, with its new Symmetry flight deck based on Honeywell’s Primus Epic avionics suite. The most striking new features are new active control sidesticks (a first for a civilian aircraft), 10 touchscreen display interfaces and both enhanced and synthetic vision systems as standard features.

The elimination of the traditional control column has opened up significant space in the cockpit and opened up access to the touchscreen panel. Pilots can still actuate the primary flight displays using cursors on the central pedestal panel, however. Human factors input from customers indicated that these displays are too far forward for most pilots to comfortably control as touchscreens. However, since FAA officials raised concern over this issue during the development of the aircraft, Gulfstream has already validated that touchscreen controls for the multi-function displays during turbulence are certifiable.

The sidestick controls, developed with BAE Systems, feature active force feedback that make it abundantly clear to a pilot when the other pilot has control of the aircraft and what they are doing with the controls. According to Gulfstream test pilots, the system delivers “classic airplane control” in terms of feel and cueing. The autopilot also provides visual indicators for the control inputs.

Another important new feature is the data concentration network (DCN), which acts a little like a virtual private network that gathers aircraft system data through a distributed high-speed network and makes it available to other systems. This advanced programmable technology is now being applied for the latest airliners (including the Boeing 787) and jet fighters.

The DCN contributes to improved aircraft availability by boosting the amount of data that can be used for health trend monitoring of all key systems. The network also reduces the need for multiple electro-mechanical devices and wiring for separate systems, benefits accrued from having a no single-point-of-failure architecture. This arrangement also reduces power consumption. The lightweight equipment can fit on a single electronics rack, freeing up space in the cabin and also boosting payload and range. The weight saving for wiring alone is a couple of hundred pounds, according to Gulfstream.

One significant safety enhancement for the new Gulfstreams is an auto-braking system that is intended to make rejected takeoffs less dangerous. The system, already in service on the G650 and G280, results in faster reaction times for applying brakes. Also, maintaining constant pressure on brakes reduces the risk of pilot-induced oscillation.

The pilot can control the braking process by pre-selecting high, medium or low settings for rates of deceleration. Other promised benefits are reduced wear on brakes and greater comfort for passengers on landing.

Less Maintenance Burden

Gulfstream’s work on reducing the cost of maintenance and improving aircraft availability has resulted in the G500/600 being prepared to enter service with 750 flight hours permitted between major inspections, which the manufacturer says is around 50 percent longer than “traditional” business jets.

All aircraft systems have been viewed from the point of view of further improving maintainability (compared with that on the G450/550/650 models). The new models feature improved access to line-replaceable units, built-in test capability and more standardized parts. Gulfstream challenged all component and parts suppliers involved in the new models to improve the mean-time-between-failure of their equipment.

Gulfstream’s PlaneConnect system transmits aircraft performance data to customers and/or the manufacturer so that they can monitor any deterioration in system performance without delay. The airframer’s health and trend monitoring system has been developed to track performance trends and identify potential system failures well before they become a problem for the operator.