Gulfstream G450 Flight Test
P1’s flight test editor Robert P Mark sees how the G450 sits within Gulfstream’s family fleet.
Being anyone’s little brother or sister has never been easy. No matter how impressive the younger sibling’s efforts, they always seem to fall short when measured against those of the older. Luckily these issues don’t happen often in the aviation world, although there certainly are cases where a new larger airplane eventually eclipsed the marketplace of the smaller.
For Gulfstream, the older of the large-cabin aircraft, the G550 and the smaller, the shorter-range G450 seem to have found just the right balance for the Savannah manufacturer. Perhaps spurred on by the fact that, according to Gulfstream, some 40 different corporate flight departments across the US operate both the G450 and the G550.
When we reviewed the G550 a few months back, we learned that aircraft could fly eight people 6,700nm in the comfort of a cabin nearly 44 feet long. The G450 hits a different sweet spot, but with a cabin only four feet shorter than the 550’s. The 450 will fly 4,300nm nonstop. Many people who regularly operate both aircraft claim it’s difficult to see or feel much of a difference in the ride from a passenger perspective, except perhaps when it comes to the number of sleeping berths available on the smaller G450 – six versus eight. Maximum seating in the G450 and the G550 is 19 although most aircraft typically operate with many fewer on board.
The speeds of both aircraft are nearly identical which leaves just one glaring difference, their price tags. The G550 lists for US$61.5M versus the G450’s US$43.15m sticker price – a cool US$18.35m difference. That means that unless a company absolutely needs the 550’s ability to fly 12-13 hours non-stop, a new G450 can be had and operated for significantly less money per hour. If these airplanes were sentient, about now the 450 would be sticking out its tongue at the 550.
On the world marketplace, Gulfstream believes the G450’s competitors are likely Dassault’s Falcon 900LX and Bombardier’s Global 5000. The French jet carries a maximum of 19 passengers, but offers a maximum range of 4,750nm, while the Global 5000 is capable of leaps as long as 5,200 nm with a maximum of 17 passengers. The price of both is similar to that of the G450.
A Little History
The G450 evolved from that same impressive heritage as other Gulfstream large-cabin aircraft. When the company decided to tweak the G-IV back in 1993 to become the G-IV SP, the new aircraft kept the same basic wing, but added a number of aerodynamic cleanups to reduce drag. The Rolls-Royce Tay Mk 611s were replaced with a “C” version of the same engine offering improved fuel consumption and a maximum landing weight increase to 66,000 pounds from 58,500 pounds. Maximum takeoff weight grew from 73,600 pounds to 75,000 pounds. The G-IV SP’s range remained about the same as the original G-IV although the increased weights translated in an improved ability to tanker expensive fuel. So popular was the earlier G-IV line that 535 of them – both G-IV and G-IV SP – were delivered, many of which are still operating today, some in military colours as various versions of the C-20. Another area old G-IV SP pilots will notice when flying the G450 is the lightness of the flight controls, something Gulfstream created to make the G450 feel more G550-like.
As Gulfstream’s model designators began to change in the first decade of the 21st Century, the G-IV SP eventually morphed into the G450 whose maiden flight came in 2003, with an entry into service following in May 2005. To sweeten interest in the G450, Gulfstream offered it to customers with many of the G550’s technological advancements as standard equipment on the proven G-IV airframe. The G450/550 also share a common type rating, another plus for companies operating both models.
In the Cockpit
The cockpit of the G450 is the same as the G550’s and offers more pilot legroom to ease that cramped feeling that can appear on long flights. Both the G450 and the G550 are fitted with the same Plane View avionics created around four 14” liquid crystal displays controlled by a mouse-like cursor device for each pilot with thumb controls for easy scrolling through a number of pull-down checkbox menus that allow the system to customize the displays to the tastes of each individual pilot. The G450/550 come standard with an Enhanced Vision System (EVS) allowing pilots to accurately view the runway and terrain ahead in a black and white display, even in total darkness.
The G450 uses the same synthetic vision system of the G550 to also show the terrain ahead in a near-3D, daylight-like visual representation of the world outside, even if the aircraft is flying in solid clouds. The G450 comes standard with a Head Up Display to reduce pilot distraction levels by placing all necessary flight information right in front of the pilot’s eyes. Another area old G-IV SP pilots will notice when flying the G450 is the lightness of the flight controls, something created by Gulfstream to make the G450 feel more G550-like.
The Head Up Display (HUD) that’s standard on the G450/G550 is worth noting since few manufacturers deliver a HUD as standard equipment. The device, built by Rockwell Collins for Gulfstream – consists of a piece of clear glass attached to the cockpit ceiling that can be positioned between the left-seat pilot’s eyes and the windshield ahead. The HUD acts like an information integrator of sorts and displays vital flight information like airspeed, altitude, rate of climb and relationship to the flight planned course. The HUD allows a pilot to focus outside the aircraft while looking through the HUD’s glass display.
While the science of how a human’s eyes can focus at both a distance and close in to a HUD screen will escape most of us, it all works well and significantly reduces a pilot’s need to continually shift their attention back into the cockpit and out again in search of flight information. Not only does alternating their focus in and out of the cockpit waste time, it’s also dangerous. The more time the pilot spends looking inside the cockpit, the less they spend looking out the window watching for other airplanes or threats.
When the G450’s EVS is in operation, the view resembles what the flying pilot might see if a powerful headlight were shown on the runway or terrain ahead. All of the EVS information can also be displayed on the HUD to make controlling the aircraft easier and to keep the pilot’s attention focused straight ahead. Best of all, the HUD acts like a superb assistant to the flying pilot when the aircraft breaks out of the clouds on an IFR approach with the crew searching for the runway. Because of the HUD, the flying pilot simply looks through the device to insure the aircraft is on course and on speed to the runway. Like many other safety devices on modern aircraft today, pilots that become used to flying with a HUD never want to fly without one again.
Feel the Power
The G450’s 13,850 pound thrust Rolls-Royce Tay Mk 611C’s uses fully automatic digital engine controls to push the aircraft up to an MMO of Mach 0.88, high speed cruise of M 0.85 and long-range cruise of M 0.80. The G550’s powerplants offer a similar MMO of M0.885, high-speed cruise of M0.87 and a long range cruise of M0.80. The maintenance team responsible for keeping those Tays humming sweetly will also notice an improvement over the G-IV SP that major overhauls at the 8,000-hour point. On the G450 that number skyrocketed to 12,000 hours while delivering a fuel burn about 4 per cent less than the earlier airplane. Both the G450 and the G550 share a significant number of parts, as well as ground infrastructure requirements that also make owning one of each aircraft much easier.
Gulfstream says the G450 requires 5,600 feet of runway for a maximum weight takeoff at sea level and 59 degrees F. In the hands of a crew that know the airplane, the G450 can be down and stopped in as little as 3,260 feet. The aircraft will carry a maximum of 29,500 pounds of Jet-A with a full-fuel payload of 2,500 pounds, or depending upon the fuel on board, a maximum payload of 6,000 pounds. No matter the load of passengers there’s plenty of cargo space available in the G450’s 169 cu. ft. rear compartment.
The G450 can be a tough airplane to pick out on the ramp, even for experienced pilots, especially since the cabins on both the 450 and the SP each sport six windows per side. A really clever pilot might notice the slightly larger G550 nose of the 450, but a sure-fire method is to look at the thrust reversers. On the G-IV SP, the reverser linkages are all external. On the G450 the engine nacelles offers nothing but a smooth clean look to airplane spotters.
Inside The Cabin
The differences between the 450 and the 550 are a bit more pronounced even though there is just a four-foot difference between them. The G450’s 40-foot four-inch cabin can be subdivided into three different seat groupings and offers no option for a crew rest station, while the G550, with its 43-foot, 11-inch cabin offers the option to divide the cabin into four seating groups, including one that will function as a quiet, forward crew home away from home with separate lighting and entertainment systems for maximum range flights. Of course the ceiling on the G450 tops out at 45,000 feet compared to 51,000 on the G550. Maximum pressure differential on the G450 makes the cabin feel like it’s at 6,000 feet when it reaches FL450. The G550 can hold a 6,000-foot cabin all the way to FL510. Both 6,000-foot cabins spell a much less fatiguing flight for everyone on board.
Steve Cass, Gulfstream’s Vice President of Technical Marketing and Communication said, “Because we take our brand rating very seriously, we feel it’s important to control the reliability and quality of our cabin completion process.” The Savannah showroom offers customers a large, well-lit room in which to choose from more than 42,000 fabric and leather samples, as well as more than 1,000 wood possibilities and other options down to the china, silver and glassware. Gulfstream also builds all the seats for its aircraft.
Maintenance Just When It’s Needed
Gulfstream created the PlaneConnect system to allow the G450 to report critical system fluctuations to ground maintenance teams early enough to head off a complete failure. Using a wireless data recorder and processor, PlaneConnect tracks, analyzes and stores vast amounts of operational data in real time during each flight. That data, captured through a number of preset parameters, is then transmitted in real time directly back to the customer’s maintenance team and very often, upon customer request, back to the Gulfstream support team.
Nearly three quarters of Gulfstream customers allow the manufacturer to see their PlaneConnect messages according to Steve Cass. That advanced heads up means, “a technician can often be ready with the solution when the aircraft arrives.” Gulfstream tech ops people in Savannah can also use an aircraft maintenance simulator to help identify problems and often create a solution while the aircraft is still airborne. For owner operators, this means replacing only necessary parts saving both downtime and money that’s often wasted when the maintenance strategy is to keep changing parts until the problem disappears.
The G450’s dispatch reliability is running at 99.9 percent over more than a million flight hours. While some manufacturers assume a 99.5 percent reliability is adequate, Cass explained the added difficulty for Gulfstream of making that seemingly small leap of an extra 0.4 percent. “Ninety-nine point five percent reliability translates into a missed trip once a year. At 99.9 percent, the operator misses one trip every five years.”
Gulfstream warranties its structures for 20 years with five to six years on the engines and five years parts and labor on everything else. With more than 800 of the G450/550 category aircraft flying in the world, there are plenty of experienced Gulfstream technicians almost everywhere on the globe. The company operates eight service centers in the U.S., with another at Luton England, Beijing and Sao Paulo Brazil.
When a rather dire maintenance problem emerges and the aircraft needs a part not readily available near a US destination, Gulfstream will dispatch a technician with the correct parts 24 hours a day, 365 days a year to prevent an aircraft on the ground (AOG) delay. Those techs are transported on one of two Gulfstream G-150s the company keeps on standby for just such situations. The company maintains US$1.6 billion worth of parts stored at strategic airport locations around the globe.
It’s a well-known fact that the only truly important element of any flight is the landing, or at least that’s what most pilots believe. That said, I might as well come clean. My first landing in the G450 left a great deal to be desired. No, that’s not quite accurate… it really was an awful arrival despite the coaching I’d had days before from other Gulfstream pilots, as well as my G450 instructor Bob McKenney before we took off. To be clear, landing the G450 is not difficult at all really. What I learned though after flying the G550 just before the 450, the smaller aircraft simply handles differently near the ground. It’s all about that wing.
Remember the 450’s 77-foot 11-inch airfoil is the same as that of the G-IV so it flies like a G-IV. The G550’s 93 and a half-foot wingspan makes that airplane just handle differently. Pilots with no previous G-IV experience before they hop into the G550 will find that in the flare, where a 550 will just plunk itself down nice and firm, the G450 can float at the slightest inkling of an over-flare. That can result in a pilot quickly finding themselves airborne once again, a few feet above the runway, with power at idle and the speed dropping rapidly.
Most pilots only screw this up once or twice I’m told.
Once I got the hang of the differences between the two airplanes, I loved the G450 as much as the G550. Both airplanes have a solid feel that even when I hand-flew the 450 around a number of late-afternoon Savannah buildups and bumps, the ride was nearly flawless. Because of the expensive technology Gulfstream installed on the G450, I felt compelled to try a fully coupled approach on the way back to Savannah. Autopilot, auto throttles and all the rest functioned nicely leaving me at minimums staring right up SAV’s runway 10. The flare – I did better this time – and rollout to me were a piece of cake.
To me, the Gulfstream G450, like its older sibling, just seems to beg pilots to grab that big control yoke and command this 74,600-pound aircraft. At least that’s what I think this airplane secretly hopes for more pilots that want to just go fly it by hand.
GULFSTREAM G450 DETAILS
Maximum Range* 4,350 nm / 8,061 km (Mach 0.80, 8 passengers, 3 crew and NBAA IFR reserves)
Normal Cruise Speed Mach 0.80 / 459 ktas / 850 km/h
High Speed Cruise Mach 0.85 / 488 ktas / 904 km/h
Mmo (Maximum Operating Mach Number) Mach 0.88
Takeoff Distance (SL, ISA, MTOW) 5,600 ft / 1,707 m
Landing Distance (SL, ISA, MLW) 3,260 ft / 994 m
Initial Cruise Altitude 41,000 ft / 12,497 m
Maximum Cruise Altitude 45,000 ft / 13,716 m
Maximum Takeoff Weight 74,600 lb / 33,838 kg
Maximum Landing Weight 66,000 lb / 29,937 kg
Maximum Zero Fuel Weight 49,000 lb / 22,226 kg
Basic Operating Weight (inc 3 crew)** 43,000 lb / 19,505 kg
Maximum Payload** 6,000 lb / 2,722 kg
Payload with Maximum Fuel** 2,500 lb / 1,134 kg
Maximum Fuel Weight 29,500 lb / 13,381 kg
Avionics Gulfstream PlaneView®
Engines Two Rolls-Royce Tay Mk 611-8C
Rated Takeoff Thrust (each) 13,850 lb / 61.60 kN
Passengers Typical Outfitting 12 – 16
Total Interior Length 45 ft 1 in / 13.74 m
Cabin Length (excluding baggage) 40 ft 4 in / 12.29 m
Cabin Height 6 ft 2 in / 1.88 m
Cabin Width 7 ft 4 in / 2.24 m
Cabin Volume 1,525 cu ft / 43.20 cu m
Baggage Compartment Volume 169 cu ft / 4.80 cu m
Length 89ft 4in / 27.23m
Overall span 77ft 10in / 23.72m
Height 25ft 2in / 7.67m
*NBAA IFR theoretical range. Actual range will be affected by ATC routing, operating speed, weather, outfitting options and other factors.
** Stated weights are based on theoretical standard outfitting configurations. Actual weights will be affected by outfitting options and other factors.
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