Posted on 08/30/2010 1:12:53 AM PDT by The Magical Mischief Tour
August 29, 2010 - Gulfstream Aerospace Corp. announced that its ultra-long-range, ultra-large-cabin Gulfstream G650 recently reached Mach 0.995 as part of its 1,800-hour flight-test program. Accomplishment establishes G650 as world’s fastest civil aircraft.
The aircraft achieved this speed during flutter testing, which evaluates the aircraft’s damping responses following an input from an external test device. Flutter testing is performed at a variety of frequencies, speeds, altitudes, weights and centers of gravity.
For the initial series of flutter tests, the aircraft achieved clearance out to both its design dive speed (Vd) and design Mach dive speed (Md) at altitudes ranging from 10,000 feet to up to the aircraft’s maximum certified altitude of 51,000 feet.
In order to achieve the maximum speed of Mach 0.995, Gulfstream experimental test pilots Tom Horne and Gary Freeman along with flight test engineer Bill Osborne took Serial Number (S/N) 6001 into a dive, pitching the aircraft’s nose 16 to 18 degrees below the horizon.
During the dive, flutter exciters introduced a range of vibration frequencies to the wing, tail and flight control surfaces to ensure the aircraft naturally dampened out the oscillations without further action from the pilots. Even under such extreme circumstances, the G650 performed flawlessly.
“The airplane is very predictable,” said Horne, senior experimental test pilot, Gulfstream. “It’s very easy to control and to get precise control at those speeds. The airplane response has matched the expectations of our engineers, and we’ve been able to easily fly the test conditions and march through the test plan.”
During the flutter test missions, a team of multi-disciplinary engineers in Gulfstream’s state-of-the-art telemetry center in Savannah monitored the aircraft’s behavior and determined real-time the damping characteristics of the aircraft.
The vibration frequencies exerted on the aircraft ranged from 2 hertz, or twice per second, to 58 hertz, or about as fast as a fluorescent light flickers. “We’re doing very well,” said Pres Henne, senior vice president of Programs, Engineering and Test, Gulfstream. “The demonstrated flutter margins met or exceeded our expectations out to maximum speeds. That’s a good sign.”
As S/N 6001 continued with flutter testing, S/N 6005 completed initial phase manufacturing and began engine testing. S/N 6005 is the fifth and final aircraft in the G650 flight-test program. Each aircraft in the program has a specific purpose, with S/N 6001 focused on envelope expansion, air data calibration, flutter, in-flight performance and flight controls.
S/N 6002 is used to evaluate the aircraft’s systems as well as its takeoff and landing performance, while S/N 6003 tests the avionics, in-flight load measurement and ice protection system. S/N 6004 will be the first G650 outfitted and tested with a full interior, which is currently being installed. S/N 6005 will participate in the reduced vertical separation minimum testing.
The G650 flight-test program officially began on Nov. 25, 2009. Through Aug. 25, the four airplanes currently flying in the program have completed more than 170 flights and 575 flight-test hours.
Pretty bird. I wonder how hard they are to fly with that bubble wrap on the controls/
I’m not certain that attaining M.995 in a dive qualifies it as “the world’s fastest civil aircraft.” Seems to me that appellation should go to the aircraft that attains the highest Vh, not Vd.
TC
I agree , Vh , Vne or Vno would be better ... I believe many commercial jets have a Vne similar to this number and can reach it in a shallow dive.
I’m with you guys. Diving aircraft have long encountered very high speeds, with some claiming supersonic back in WWII. What is impressive is the way the plane didn’t go haywire while transonic. Seems to have been well engineered.
The bubble wrap is there to give the pilots something to do when on auto-pilot. Previously coloring books were used, but the crayon and crayon shavings got smooshed in cabin spaces, not to mention the best picture pages being colored first caused cabin tensions, much like the previous practice of using ‘Knock-knock’ jokes.
Mmmm. New airplane smell.
}:-)4
I wonder how long it will take before Rush buys this model?
It’s different with Al. He’s despoiling the environment, but it is for us. It hurts him, it really does, but the mission is so important, that like Jesus carrying the Cross, he must struggle on.
What’s the price?!
How’m I spozed to know how much to take outta my piggybank?
Wonder how long it will be before Rush buys one of these.
Reminds me of my girlfriend’s kid circling all the hidden pictures in his Highlights magazine then leaving it in the bathroom to mock me.
Pelosi is gonna want one.
> What’s the price?!
>
> How’m I spozed to know how much to take outta my piggybank?
You have to buy it to find out the price (paraphrasing Nancy Pelosi).
>>Mmmm. New airplane smell.
}:-)4<<
I’ll bet the stewardesses taste great too.
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