For nearly half a century, Gulfstream has been synonymous with Savannah, and in recent years the business-jet brand has grown to dominate the economy of this compact, riverside city of tree-lined squares and colonial charms. The company’s prospects matter for many thousands of families, so you might imagine important new product developments would be talk of the town and beyond. Yet for much of 2013 and 2014 – within its campus of buildings next to Savannah’s airport – Gulfstream managed to keep a big secret from much of the world: the precise nature of its P42 project, a launch that the General Dynamics subsidiary had been working on for several years.
When that programme emerged, in October 2014, not as one aircraft but as two, many assumed that the G500 and G600 would replace the G450 and G550. Gulfstream’s two existing large-cabin, long-range types, which slot below the flagship G650 and G650ER, are around a decade old and face fresh competition from the likes of the Dassault Falcon 8X. Instead, Gulfstream further surprised the industry by stating that, rather than taking the place of the G450 and G550, the G500 and G600 would be offered alongside the older aircraft, giving customers an unprecedented six variants to choose from in the 4,350nm (8,060km) to 7,500nm segment.
In terms of range, the new duo fit between the G450 and the G550. The G500 – the first of the two to market with a scheduled entry into service of 2018, and the subject of this technical description – can fly for 5,000nn at Mach 0.85. The G600, meanwhile, which will enter service a year later, is able to make 6,200 at the same speed. The G550, by contrast, can cope with 6,750nm, but at a slightly slower M0.8, while the G450 offers 4,350nm, also at M0.8. All four stop short of the G650’s range of 7,000nm at M0.85, while the newer, top-of-the-range G650ER can go even further: 7,500nm, also at M0.85. Maximum operating speed for the G500 and G600 is M0.925, the same as the G650.
Gulfstream kept details of its G500 and G600 firmly under wraps until last year
Gulfstream
While these nuances are, of course, crucial to flight departments, the G500 and G600 bring a lot else to the party in terms of innovation. For a start, they have an all-new fuselage: Gulfstream now uses three different ‘tubes’ for its three families of long-range aircraft. The G500 and G600 are wider and come with more headroom than the G450/G550, with 2.41m cabin cross-section and cabin height of 1.93m. This compares with the 2.26m-wide and 1.89m-high G450 and G550. They use engines from Pratt & Whitney Canada rather than Gulfstream’s long-running vendor Rolls-Royce, and include, for the first time on Gulfstream aircraft, active control, fly-by-wire sidesticks.
Gulfstream’s Scott Neal, senior vice president of worldwide sales and marketing, dismisses suggestions that having six types in a segment of the market where, just a few years ago, it had three, will confuse customers or simply dilute sales that Gulfstream would have secured anyway. “We are very comfortable with the way the aircraft are spaced. There are key differences in range and cabin size,” he says. Prices are fairly evenly spaced too, with the $50 million G550 coming between the $45.5 million G500 and the $55.5 million G600, and the G450 at $34 million, giving customers more entry points to the brand.
While the G450 will remain strong in the domestic market, particularly for coast-to-coast missions, the G550 offers that additional range that the G600 cannot. G500 and G600 customers, however, will be swayed by the additional cabin size, advanced flight deck and speed for international trips, he says. His boss, chief executive Mark Burns endorses this view. “We are now spread very effectively from the G650 down to the G450,” he maintains. “The G650 speaks for itself and the G500 and G600 play off the strengths of the G650. We have three fuselage sizes to offer, with the aircraft offering different performances. We feel good about the way we’ve segmented it.”
However, it seems likely that, at some point, despite its price advantage, the G550 may become squeezed out by the G600. If Gulfstream offers a range extension – as it often does with new types following entry into service – the range advantage of the G550 will become eroded, especially given the higher speed of the G600, not to mention its more advanced cockpit technology and longer, wider, higher cabin. That said, the G600’s entry into service of 2019 gives the G550 a head start. The G450, on the other hand, looks less threatened by the G500, given its $11 million price advantage and very distinct niche in the market as a US domestic workhorse.
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Among a spate of new departures for the G500 and G600, two perhaps stand out – what the pilots will experience is markedly different to any other Gulfstream thanks to a new Symmetry cockpit. And, for the first time on a modern, large Gulfstream, the aircraft will not be powered by Rolls-Royce. Neal says the decision to opt for the 15,100lb-thrust (67.2kN) PW814 for the G500, and the 15,700lb-thrust PW815 for the G600 was made after a rigorous competition. “We get asked all the time about why we went for a different engine supplier, and when we explain it our customers are very comfortable with it,” says Neal. “Rolls-Royce will continue to be a very valuable supplier.”
The 10,000-20,000lb-thrust class PW800 was launched in 2008 after Cessna selected it for the Citation Columbus. After that programme was cancelled the following year, P&WC continued to test and demonstrate the engine – which is derived from the PurePower PW1000G geared turbofan for airliners, and competes with GE Aviation’s Passport 20 and Snecma’s Silvercrest – as well as Rolls-Royce’s BR725 in business aviation. Unlike the Mitsubishi Regional Jet’s PW1200G, which it most resembles, the PW800, with redesigned low-pressure spool, is optimised for high-altitude cruise rather than the frequent take-offs, lower altitudes and lower speeds of regional jets, says P&WC.
However, it is in entering the cockpit of the G500 or G600 that the most visible change from existing large Gulfstreams is evident. Although the G650 is fly-by-wire, the new aircraft are the first business jets with active-control sidesticks, a technology that allows each pilot to feel the inputs of the other and greatly improves situational awareness in the cockpit, enhancing safety, says Mike Cuson, director of entry into service for the G500 and G600 programmes. Former military pilots may feel at home. The sidesticks were developed by BAE Systems for the Lockheed Martin F-35, and are also present on the Embraer KC-390 transport.
Gulfstream says its investment in pre-flight testing facilities has paid off
Gulfstream
Introducing the sidesticks recreates the mechanical link that pilots experience when they use traditional control columns, says Mark Kohler, vice president of advanced aircraft programmes. “With fly-by-wire you no longer have a direct link to the flight controls. On the G650, even though you have a central control, it still ends up as wire,” he says. Gulfsteam, therefore, decided to take it one step further with active sidesticks. “Sidesticks open up the space [in the cockpit],” he says. “But they are also more efficient, and by making them active you reintroduce that mechanical connection. The complexity goes up, of course, so picking a supplier like BAE was important to us.”
The new Honeywell-provided Symmetry flight deck also introduces several changes, with 10 touchscreens replacing most of the traditional switches, and a “tidied up” overhead console, says Cuson. A touchscreen menu system is being developed with the target of making 90% of the functions a pilot needs available under five tabs, representing different phases of a flight: start-up, taxi, take-off, en-route and arrival. An Enhanced Vision System heightens pilot awareness in low visibility and is standard on the G500 and G600. An improved infrared sensor boosts resolution by 400%, and camera enhancements provide a wider field of view, says Gulfstream.
Despite the radical differences, however, those familiar with the manufacturer’s products will feel at home, argues Cuson. “We have taken many current Gulfstream pilots into the simulator and within minutes they feel comfortable with the new technology,” he says. “Much of the design, look and feel is similar to existing products. They are not startled.” Gulfstream customers are used to change, adds Neal: “We have always been innovators on the flight deck. We were the first with a glass cockpit, the first with a head-up display, the first with synthetic vision. Now we are the first with active control sidesticks in a business jet, and the first touchscreens in a large cabin aircraft.”
Customer feedback – and not just from pilots – has been crucial to the design of the overall aircraft, says Gulfstream. Select customers comprising what the manufacturer calls its 35-strong Advanced Technology Customer Advisory Team were briefed twice a year on progress, under non-disclosure agreements. These pilots, flight attendants and representatives of flight operations and maintenance departments suggested numerous tweaks. “As a result, over 200 design changes were made,” says Cuson. “They truly have put input into what the final product looks like. The fingerprints of our customers are all over these aircraft.”
Customers were heavily involved in the cabin design
Gulfstream
This was particularly true when it came to the cabin. Gulfstream has invested in a G600 cabin mock up – the G600’s 13.8m-long cabin, not including baggage area, is 9.1cm longer than the G500 but identical to its sibling in almost every other way. “We invited people into it at NBAA [in October] last year and we followed them around with an iPad noting what they said,” says Cuson. “We will have the mock-up again at NBAA and you will be able to see what changes we made as a result. They wanted as much space as possible, they wanted the latch design changes so opening cabinets was quieter, deeper cup holders, a wider ledge, more storage for iPads and different lighting.”
The G500, which can carry 19 passengers, has 68.5cm-wide seats with articulating footrest and the same porthole-style windows as the G650 – 15% larger than those on the G550/450. There are height adjustable, pedestal-mounted conference tables, and Gulfstream says the G500 is the only aircraft in its class with the option of forward or aft galley. Although cabins are fairly customisable, customers have no choice over where their interior is installed. All Gulfstream completions are carried out in-house, either in Savannah or at its newly expanded Long Beach facility. “The reason is that you don’t want it to be a Gulfstream with someone else’s interior,” says Neal.
Structurally, the G500 and G600 wing will be based on the G650’s, although for the first time Gulfsteam has brought the wing and tail design and assembly in-house. There had been concerns with the supply chain’s ability to deliver wings on time on previous programmes – Spirit Aerosystems for one running into difficulties – but Gulfstream says the decision to build the structures next to its final assembly line in Savannah is to “give us more flexibility in the build cycle”. Burns adds: “We looked at industry capacity and we had a competition, but we decided to meet the capacity needed in house. We will do the same exercise in future for all our products.”
Production of the first G500 is under way in a new final assembly line facility, one of two recently constructed buildings on the Savannah campus (the other makes the wings for the two aircraft). Two older buildings closer to Savannah airport’s terminal house the final assembly lines for the G550/450 and the G650/G650ER. When we visited in October, there were three G500s in assembly in addition to the three already with the flight test department. Manufacture of the first G600 flight test example – the programme is roughly 18 months behind the G500 – is underway and the type, says Gulfstream, is on track for its first flight in 2017.
There are four main areas in the final assembly line. Fuselage panels arrive from suppliers and are pieced together using a Broetje machine. On the next station the sections are joined to make the recognisable fuselage barrel, before wings, tail, engines and landing gear are fitted. On a final station, the likes of farings and windows are installed before the aircraft is set for power-on and ground testing. The process is much more automated than is traditional on a Gulfstream product thanks to processes such as chemically bonded stringers – introduced for the G650. “On a G650 there are 80% fewer fasteners than on a G450 or G550,” says Gulfstream. “This evolves it further.”
The first flight of the G500 took place on 19 May with N500GA staying in the air for 2h 15min and reaching an altitude of 15,000ft. After a pause of “several weeks” to prepare the aircraft for flutter tests, flight testing resumed in August. By mid-October, the jet had surpassed more than 100h of flight on “more than 45 missions”, the longest of which was 5h 22min. The aircraft has reached an altitude of 38,500ft and maximum airspeed of M0.8. “This plane has been flying exactly as expected, which highlights our commitment to quality and our attention to detail,” says Dan Nale, senior vice president, programs, engineering and test.
Of the four test aircraft, the first, T1, is focused on flight performance and controls, with the second, T2, on flight loads validation. T3 is used mostly to test avionics, and T4 human factors and supporting systems. The programme also includes an aircraft with a fully outfitted interior. Gulfstream said on 14 October that it had completed initial testing of the aircraft’s handling qualities as well as its high-speed and attitude recovery stall system. Flutter and envelope expansion testing was continuing on T1, while T2 and T3 were being prepared for flight. The G500 has also completed static-limit load-testing on its primary structural components.
Gulfstream has invested heavily both in research and development laboratories but also in ground testing facilities, and places great store on the fact that its extensive pre-flight development process has allowed flight testing to pass smoothly. Some 37,000h of testing have been carried out on its so-called system integration bench, integration test facility (ITF) and separate iron birds for the G500 and G600, a process that will continue until the turn of the decade. “We’ve had no maintenance squawks,” says Kohler. “We are convinced that the investment in the labs has allowed us to do this. We have been able to mature hardware and software in a controlled environment.”
Gulfstream introduced its ITF for the GV programme to integrate Honeywell devices in overhead panels. “We’ve taken that a step further to create a fully visual system,” says Kohler. “It’s more wraparound. It gives pilots all the visual cues they need.” The system integration bench has been running for five years and is “very centric to evaluating Honeywell avionics and the data concentration network”, says Kohler. Integrating the active control sidesticks has also involved extensive work in “developing the control laws which would be the interaction from the pilot through the sidestick. It was new technology for us and we had very strict design requirements.”
The transition of Gulfstream has been remarkable from its dark days of the 1990s when its workforce numbered in the hundreds and it went through several owners after being divested by original parent Grumman. Under General Dynamics, the company has enjoyed a decade and a half of intense investment and product development, introducing more than half a dozen new types as well as acquiring its mid-cabin portfolio – what are now the G150 and G280 – from Israel Aerospace Industries. Since 2006, Gulfstream has more than doubled its Savannah workforce to 10,000, with a further 6,000 working elsewhere, including the company’s maintenance and completion centres.
Gulfstream argues that it has managed to keep an edge in the sector because it has invested heavily in R&D. Gulfstream opened its first R&D centre in Savannah in 2006 and now there are four buildings, all situated close to the new G500 and G600 final-assembly line, and employing a total of 1,700 engineers. According to Burns, General Dynamics insists on high levels of R&D spending, especially between programmes. “It’s the view of our chairman that we have to be continually investing in new products,” he says. Before 2006, the company had tended to hire engineers on contract when it had a new programme to develop, and released them afterwards.
Although Gulfstream continues to face strong competition from Dassault – which is currently bringing two new products, the 5X and 7X, to market – Bombardier’s problems have seen it lose ground in an intensely competitive long-range, large-cabin segment. In July, the Canadian manufacturer announced a two-year delay in its 7,300nm-range Global 7000, taking entry into service to the second half of 2018. The even longer-range Global 8000, originally scheduled for 2017, is likely to face a similar wait. This gives Gulfstream several years of exclusivity in the 7,000nm-plus range segment. “Our G650 remains a unique product,” says Burns.
With its current six models, Gulfstream is on track to build 150 aircraft this year, around the same as last year. As for products beyond the G500 and G600, Burns is understandably tight-lipped. Of all of its aircraft. the midsize G150 faces most competition in a slow-selling segment. While Gulfstream remains committed, he admits “the market will decide the G150’s future”. As for one of the most elusive concepts in the industry, Burns says there are no near term prospects of a supersonic business jet from Gulfstream. “But as the technology evolves, we’ll become more and more interested,” he says. “We continue to invest hours in understanding the technology.”
Gulfstream may have kept quiet about the G500 and G600 for several years, but it is making plenty noise about the programmes now. After more than a decade in which emerging markets overtook the USA and Europe in terms of demand for this most American of brands, the economic slow down in Brazil, China and Russia is seeing sales swing back, and this year Gulfstream expects some 60% of its deliveries to be to its traditional markets. With the arrival of the G500 and G600, the manufacturer is giving customers in this segment more choice in range, speed, capacity and price than they have ever had.
Source: Flight International
