Gulfstream sticks to its traditions with the G650

Gulfstream has launched its G650 widebody business jet. A new Gulfstream is big news and the G650 looks, well, like a Gulfstream. It looks like a pumped-up G550, but it’s all-new, including the type certificate, which will say GVI – sixth in an illustrious line stretching back 50 years to the GI (my favourite).

It’s bigger, faster and flies further than the G550 – bigger, faster and further enough for Gulfstream to put the G650 into a different market segment (ULRVLJ – ultra-long range very large jet?) and keep building the G550. But where does all that extra speed (Mach 0.925) and range (7,000nm) come from?

Where’s the swoopy wing and radical area ruling? The G650 looks so…Gulfstream.

The G650 will be the fastest civil aircraft flying, squeaking ahead of Cessna’s Mach 0.92 Citation X. But the X looks fast – highly swept wing, scuplted fuselage, humongous engines. The G650 looks so…smooth, effortless. It’s the wing, I think; it looks deceptively simple.

G650 (aqua) versus G550 (lavender – what’s with those colours?)

It’s a Gulfstream wing, so there are no leading-edge devices, just lots of area for high lift. And there are no flap track fairings, just lots of span for low drag. There’s a bit more sweep, but not too much, and none of the radical contouring you see on, say, a Global Express wing. I like the Global Express wing; it looks so…technical. But there is an elegance to the G650 wing.

Gulfstream’s Pres Henne says that, compared to the G550 wing, peak aerodynamic efficiency (ML/D*) has been improved by 8% and pushed out by 0.055 Mach to M0.855 – enough to make the G650 as efficient at M0.90 as the G550 is at M0.80. And Henne expects the G650 to spend a lot of its time at around M0.90.

Something that is very familiar about the new aircraft is its imposing stance on the ground, but the tail has been lowered to reduce the rake of the fuselage and bring the aft baggage door closer to the ground to make loading easier. The G650′s design might not be ground-breaking, but is most definitely a Gulfstream.


*ML/D – Mach number x lift/drag ratio


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