The aircraft has both Iridium and Inmarsat SatCom systems, and its audio-visual system components run the gamut, accessed by dual USB input ports and dual 26-in. LCD monitors.
We recently strapped into the left seat of S/N 6013 for an evaluation flight. Jake Howard, G650 project chief test pilot, was in the right seat and Tom Horne, senior experimental test pilot, rode on the jump seat and recorded data for our test points.
The aircraft's empty weight was 54,372 lb., giving it a potential 1,428-lb. full-fuel payload. Thus, this aircraft can carry seven passengers with full fuel. Each additional passenger, however, only costs about 35 nm of range.
Fuel on board our flight was 15,600 lb., about 35% of maximum. Horne computed the ramp weight at 70,022 lb., or about 70% of maximum. With a field elevation of 50 ft. and outside air temperature at 25C, our computed takeoff speeds were 108 KIAS for V1, 109 KIAS for rotation and 126 for the V2 one engine inoperative takeoff safety speed. TOFL (takeoff fueled length) was 3,400 ft.
Engine start procedure involved switching on the boost pumps, turning on the start master and pressing a start button. Next, open the fuel cock and the Fadec (full authority digital engine control) handles the rest.
With a takeoff weight of about 69,600 lb. and 37,800 lb. of thrust, acceleration was sporty, even by Gulfstream standards. The aircraft left the runway in about 3,000 ft. Control response was crisp and the aircraft was well damped in pitch, no doubt due in large part to the 36.6-ft. span, 439-sq.-ft. horizontal stabilizer. But the high-level FBW control laws surely played a significant role as well in G650's well-mannered behavior.
The aircraft also had pleasant artificial roll control feel and good roll response with adequate control yoke centering, but very little on-center break-out force. Engineers with Gulfstream and Rockwell Collins, which supplied the control yokes and rudder pedals, worked together closely to fine-tune artificial feel and control response.
On the way up to initial cruise altitude, we had a couple of intermediate level-offs required by air traffic control (ATC) and comparatively sharp turns. Yet, using a 250 KIAS/260 KIAS/Mach 0.85 climb schedule in mostly ISA conditions, the aircraft leveled off at FL 470 in 23 min. At ISA-7C, it cruised at Mach 0.85 or 480 KTAS on 2,400 pph at a weight of 67,500 lb.
Then we pushed up the throttles because high-speed cruise is G650's forte. The 67,400-lb. aircraft smartly accelerated to Mach 0.90, resulting in 506 KTAS on 3,000 pph in ISA-7C conditions. Horne noted that the cabin altitude was 4,300 ft.