G V beats NRT-IAD Speed Record.

ERJ - Jay

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Ok quick question: Who's got the GV on order? Anyone? Sounds really nice.

Thursday March 14, 9:55 am Eastern Time

Press Release

SOURCE: Rolls-Royce

Rolls-Royce BR710-Powered Business Jet Breaks Speed Record
CHANTILLY, Va., March 14 /PRNewswire/ -- A Gulfstream V business jet powered by Rolls-Royce BR710 engines has broken a 44-year-old speed record for the set course between Tokyo's Narita Airport to Washington-Dulles International.

Accompanied by four passengers, Gulfstream demonstration pilots Gregory S. Sheldon and Robert S. McKenney flew the aircraft at an average speed of 566 mph. They completed the 6,739 statute mile flight in 11 hours, 54 minutes.

Ian Aitken, President - Corporate Aircraft, said: ``The demanding schedules of many of today's business travelers require an aircraft that can provide quick, reliable, efficient transportation between major city pairs. This record-breaking flight further demonstrates these key characteristics of the BR710-powered GV. We congratulate Gulfstream and its pilots on setting this new record.''

The BR710 is the exclusive powerplant for the GV and the new, extended range Gulfstream V-SP, which is powered by an enhanced version of the BR710 and is scheduled for delivery in 2003.

On April 8, 1958, a Boeing KC-135 Stratotanker set the original record- breaking flight in 13 hours, 46 minutes, traveling at an average speed of 492.26 mph. Gulfstream broke that record in the ``unlimited'' category, which specifies both aircraft are jet powered but are in different weight classes. The record now awaits final certification by the National Aeronautic Association in the United States and the Federation Aeronautique Internationale in Switzerland.

Rolls-Royce is a global company providing power for land, sea and air. It employs some 42,000 people in more than 30 countries, including over 26,000 in the UK, 5,000 in the rest of the Europe and over 8,500 in North America. The company has a balanced business portfolio with leading positions in civil aerospace, defence aerospace, marine and energy markets. With annual sales of around 6 billion pounds Sterling and a forward order book of nearly 17 billion pounds, its technology is applied over a wide range of products that generate high-value services throughout their operational lives.

Rolls-Royce is the only engine manufacturer powering commercial aircraft in every segment of the market. It has customers using both fixed and rotary wing aircraft in over 150 countries, including more than 500 airlines, 4,000 corporate and utility operators and 160 armed forces.

Rolls-Royce is also a global leader in marine propulsion, engineering and hydrodynamic expertise, with a broad product range and full systems integration capability. More than 2,000 commercial marine customers and over 50 navies use Rolls-Royce propulsion systems and products in 20,000 ships. Navies alone operate 1,000 gas turbines.

In the energy markets, the company has supplied more than 5,000 units to customers in nearly 120 countries and is investing in new products and capabilities for the oil and gas industry and for distributed electricity generation.

The company has some 53,000 gas turbines in service worldwide and has pioneered gas turbine technology for aerospace, electricity generation and marine propulsion. It is involved in major future programmes in these fields, including the world-leading Trent aero engine family, WR-21 marine engine, leading-edge water jet propulsion systems, and combat engines for Eurofighter Typhoon and the F-35 Joint Strike Fighter.

SOURCE: Rolls-Royce
 

GVFlyer

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GVSP

Everybody is getting GVSP's on order now. The SP has better range and speed than the GV and an upgraded avionics suite. The SP will be capable of 6750nm @ M.80, 6000nm @ M.85, and 5000nm @ M.88. New generation avionics will provide an additional 6 feet of cabin length, save 220lbs and add four 14.1 inch, active matrix, full color LCD displays to the cockpit. A unique side arm Cursor Control Device will add to the functionality of the displays. A Forward Looking Infared Enhanced Vision System and Heads-Up Display (HUD) are standard. In the back, 25% additional baggage space will be picked up through the use of conformal vacuum lav and water tanks.
 

empenage

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Cool:

But Bombardier will send a Global out as soon as the winds are favorable to beat that record. The competition is fierce. At least you can get a GV from Gulfstream. Bombardier holds onto their Globals like they are gold. Ours is already 10 months late! Poor workmanship at completion. Old Teddy Forstman was smart buying K C Aviation. He set Bombardier back 4 years with that move. I miss dealing with Gulfstream. They do it right.

Later.
 

GVFlyer

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Global Excuse

The Global Express has never beat a Gulfstream V record in a completed airplane (outfitted with an interior). A fact that Peter Edwards and his boys don't point out. The record flights from Hilton Head to Maui and the New York to Tokyo flights, about which they made so much hoopla, were done in "Greenies." The over 65 world records that the GV has, with the exception of the 13:30 climb to 51000 ft., were made in completed aircraft on customer demonstration flights or flights to airshows with eight or nine passengers and their baggage.

Right after certification Bombardier made the boast that they were going after the GV records. As soon as they realized that the GV was a significantly faster jet at 38,000 feet or above, they gave that up. They have never achieved their claimed range of 6,500nm. Even Luc Fouquette will admit that. Gulfstream engineers determined the actual range of the GX to be 6240nm. You see, the only FAR Part 25 certified data in the Aircraft Flight Manual is takeoff and landing data. The cruise charts only have to be "representative of a test article in the test program." In other words, a green aircraft. Gulfstreams cruise data is conservative, they know that the GV will fly 6500nm not only because their demonstrator SN502 did it many times before certification and many customers did so after cert, but also because during Function and Reliability testing they flew interior loops around the USA, the longest of which was 6771nm and 14 hours 48 minutes landing with NBAA reserves.

The only Challenger or Challenger derivative that I've flown is the CL 601-3A on which I flew a modified closed loop handling qualities evaluation for military source selection. It was an underpowered, buffet limited aircraft. We chose the G-IV. It's significant to note that in every military competition the Gulfstream has won the fly-off. First for the G-III against all comers, then the G-IV and finally the GV against the Global Express and the Boeing Business Jet.

When evaluating the Global Express it doesn't take a physics major to realize that there is something wrong with Bombardier's claims. Both have the same BR 710A1-10 turbofan engine producing 14,750 lbs of thrust. The GV weighs 90,500 lbs at take-off; the GX 96,000 lbs. It would be unlikely that the heavier jet could meet the performance of an aircraft that is 5% lighter with exactly the same thrust. The GV will always carry more payload than the GX and burn less fuel on the same length trip. The GV will always go farther using less fuel than the GX. For example, the GV will burn 38,320 pounds of fuel on a 6500nm trip; the GX will burn 40,350lbs going 6240nm.

The GV wing, as produced by Northrop Grumman in Dallas, is a beautiful thing, designed with CAD, CATEA and Computational Fluid Dynamics on the same computer that designed the Boeing 777, it's an all lifting device with no washed out or washed-in regions, no stalled regions, even the radius going to the winglet is lifting. The winglet is set on such an angle as to provide a forward thrust vector - much like a sailboat tacking into the wind. Gulfstream has flown the GV from 72 knots to 1.07 mach with no adverse effects. The wing is U-2 long and exceptionally wide producing 1136 square feet of wing supporting 90,500 pounds of jet for a wing loading of 79.66 pounds per square foot. The Global wing is 1022 square feet for a wing loading of 94 pounds per square foot. This makes the Global another buffet limited airplane. I've done 45 degree bank turns in the GV at 51,000 feet. This would be a suicide attempt in the Global Express.

The design philosophy for the Global wing concerns me. Current aerodynamic wisdom professes that a sweep of less than 30 degrees is ideal for subsonic flight. The GV sweep is 30 degrees, the Boeing 737, the DC 9, the Airbus 300, and the Fokker 100 all have sweeps of between 24 and 28 degrees. The Global Express wing is swept 35 degrees. As sweep increases longitudinal stability decreases, adverse Dutch Roll characteristics increase and tip stall speed becomes lower. My guess is they dramatically swept the wing to reduce drag on a draggy wing. The wing is a supercritical design. Again I think they did this to reduce drag on a wing made thick in an attempt to contain as much fuel as possible. With a supercritical design you can either reduce thickness over cord (T/C ratio) to reduce drag or thicken the wing and maintain equivalent drag. In an effort to put all of the fuel in the wings, Bombardier came up with a wing that was 12% T/C, about the theoretical aerodynamic limit as to how thick a wing can be (the GV wing is 8.4% T/C). Something had to be done. The radical sweep and the supercritical wing are a series of kluges to compensate for what I view to be a poorly designed Japanese wing. The airplane is a hand-full in a crosswind; even the factory pilots drug a wingtip during development. Two 604's which embody the same design philosphy, have struck a wing-tip on takeoff in the last 15 months killing all on board; one at Wichita and the most recent at Birmingham England on 4 Jan 02.

Late in the program Bombardier found that they were unable to tune the airflow between the wing and the nacelle to reduce drag and increase lift as Gulfstream had done because engine placement is much farther aft of the wing on the GX. As a matter of fact, the area around the engines had become a high drag region. Bombardier's answer was to area rule the fuselage in the area of the engines. You can see this after the fact modification in the coke bottling of the fuselage in the vicinity of the engines.

There are several things about the GX that I don't like.

It pitched up during the stall testing and the stall chute had to be pulled. A pitch-up is the worst thing that can happen during stall testing. The wing blanks out the horizontal stabilizer making recovery impossible without a stall chute. Pitch-up has been characteristic of every Bombardier large cabin aircraft. They lost a 601 with two fatalities for this reason during developmental test. No Gulfstream has ever pitched up during certification stall testing.

The Global Express has severe CG limitations, you must buy it with a forward galley so as not to exceed the aft cg limit. The more aft the cg, the more unstable the aircraft.

The Global Express has a 2000 pound fiberglass fuel cell within the secondary burst radius of the engine. The vent lines from the wings to this fuel cell run through the pressure vessel.

In an effort to save weight, the GX has no air to air heat exchangers. They use exotic materials to send extremely hot customer discharge air forward through the pressure vessel. If there was a bleed air leak in the GV (this has never occurred) you could find he leak by the noise; in the Global Express all you would have to do is locate the flaming passenger.

In the flight controls, the GV offers full manual reversion. If you have a complete hydraulic failure in the GX, you will die.

GV dispatch rates have been around 99.5%, GX rates have been less than 98%. Anecdotally, there were two dead GX's at Luton the last time I was there, one AOG for leading edge devices the other one was just broke.
The Sprint GX was recentlly down for blowing up a generator, the other three generators were found to have metal in them. The GV uses completely different and extremely reliable Independent Drive Generators.

The Global Express instrument panel is not large enough to fit the six 9 inch displays currently on the Gulfstream V; Bombardier had to use 8 inch display units. The GVSP is using 14.1 inch full color LCD display units.

From a comfort stand point with the concommitant fatigue issues, the GV maintains a 5960 ft. cabin at 51,000 feet. The Global Express, should it ever be able to reach 51,000 feet will have a 8000 foot cabin.
 
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Postflight

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Hi GVflyer,

For the most part, yours was a well-written post, in which you make quite a few valid points.

I do take exception to a few comments:

Yes, both the Challenger and Global Express use a supercritical wing; however the original CL600 (and all 60x Challenger variants) are based on a design by Bill Lear--the LearStar 600, which Bill sold to Canadair in 1976. The Canadians dramatically increased the fuselage diameter (prompting Lear to refer to it as “Fat Albert,” and entering into unsuccessful legal action to regain design control). It is NOT a “Japanese wing.” And I was under the impression that the Global’s wing was “a completely new design” (but then, we know how manufactures through around that phrase).

The supercritical wing design itself is not a “kludge” (unless the aircraft is designed to be flown inverted). It, like area ruling a fuselage (recall F-106 vs. F-102), is a very efficient trans/supersonic aerodynamic design tool. You also fault the Global X for its 35 degree swept wing, while praising the GV (a "DARN" fine airplane!) for using a less steeply swept wing. The examples you cite are “Boeing 737, the DC 9, the Airbus 300, and the Fokker 100,” to show the superiority of the less swept GV wing. The 9, F100, and 737 are hardly “high speed” jets, with normal operating Mach numbers well below .80 (the F100’s MMO is only .77!). Along the same lines, you state that the Global is a “buffet limited aircraft” due to its wing loading. Given the same airfoil and the same wing sweep, the aircraft with a higher wing loading will reach high speed buffet at a more limiting Mach number; however, the two “kluges” you mention, increasing wing sweep and using a supercritical wing, significantly delay the onset of Mach buffet (just as dose reduced wing loading). BTW, the 747 uses a 39 degree swept wing, and the Citation X uses the same 35 degree sweep as the Global.

I trust your observations about the real world performance of the two aircraft (GV and Global Express), I have not had the privilege to fly either. If I did have a choice, given your input and that of my friends operating Gulfstreams, I would make the same choice you have. Please don’t take offense at my quibbling. I have been lurking on the board for a while and always enjoy reading your posts. The “Japanese wing” comment and praising the GV wing (which IS worthy of praise) because of its similarity to the F100 wing (which is anything BUT a high speed wing/aircraft), prompted me to comment.

Sorry for the length of the post, and again, please understand I mean no disrespect.

Best Regards,
Postflight
 

GVFlyer

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Global Express

Postflight,

No offense taken.

The Global Express wing was designed and is manufactured by Mitsubishi Heavy Industries in Nagoya, Japan. The wing and mid-fuselage section containing the spar carrythrough structure is built in Japan and subsequently shipped to Canada for final assembly.

What I was suggesting about supercritical wing usage is that while in most applications this design is used to achieve a lower local mach number on the wing upper surface than on a laminar flow wing and to cause the termination of supersonic flow once Mcrit is exceeded through gradual deceleration thereby avoiding a shock wave and it's associated drag, this is not the case on the Global Express. Bombardier was trying (and failed) to get all of it's fuel in the wing. In so doing, they ended up with a very thick wing. Another use of supercritical wing design is to manipulate thickness. After they could make the wing no thicker they ended up with a 2000 lb. fuselage tank.

During the early stages of developmental testing, Pete Reynolds and his band of test pilots found that strong shockwaves were forming in the engine nacelle, pylon/fuselage area. This required recontouring of the fuselage to produce a waisted shape for application of the area-rule concept to minimize drag. While this might be a good idea for a F-106, it diminishes interior volume on a transport category jet and you only resort to area-ruling if you have to.

I fault the use of radical sweep on a wing because of the aerodynamic penalties paid for the minimal gain. As I stated before, as sweep increases longitudinal stability decreases, low speed handling becomes more difficult, Dutch Roll characteristics become worse, tip stall speeds decrease, and the wing aspect ratio decreases causing more induced drag. This later characteristic is particularly dangerous during take-off and landing. There have been two recent fatality accidents in Challengers involving loss of control during takeoff. In part, I fault the design. I knew one of the pilots that died on runway 19 at Mid Continent and had worked with the flight test engineer on board before he went to work at Bombardier. They were competent professionals.

The beauty of the GV wing is that they were able to get better high altitude maneuverability, achieving in unaccelerated flight at 51,000 feet a window of over a 100 knots between compressibility and stall, and great hot and high and short field capabilities without resorting to excessive wing sweep or leading edge devices. I cited the airliners because of their conservative wing design not because there is any similarity between their wings and the GV wing. There is not. Did you know that the upper surface of the GV wing is a single piece of extruded aluminum? This is new technology used by Gulfstream to achieve the cleanest low drag wing possible. The wing is clean top and bottom. There are no "canoes" hanging down for the slotted Fowler flaps.

I know the Global Express is severely buffet limited by looking at it's MMO numbers above 38,000 feet. Far 25.335 requires that you reduce VC/MC .07 mach below the point at which you encounter mach/compressibilty effects. Looking at the height velocity curve you will see a steady MMO decrease from 38,000 feet to 51,000 feet tracing the edge of buffet.

Yep, I know the whale has a big sweep, so does the TriStar at 35 degrees, but it also encounters tip stall at .72 mach.

Have you flown the Citation X? So many pilots have drug the wingtip on that thing that Cessna just came out with a flight control mod to help minimize the problem. By the way, did you know that the C750 has such a dramatic drag rise as mach increases that at .92 it's NBAA IFR range with 8 passengers is just 750 miles; maybe that's where they came up with the C750 designation. Right after Gulfstream beat the Citation X New york to Los Angeles speed record, I was going through GV recurrent at FSI. In the GV initial class was a Cessna Test pilot, Wayne S. Cessna had sent him there to learn where the GV's weaknesses were. Wayne went back to Wichita disappointed and Gulfstream now advertises the GV as the fastest business jet beyond 2000 nautical miles.

Cheers
 
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knelson

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a few excellent posts here, thanks for the well thought-out, informative replies here. I enjoyed the discussion and hope I get a chance to fly any of the airplanes mentioned here!

knelson
 

CitationCapt

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The 750

"Have you flown the Citation X? So many pilots have drug the wingtip on that thing that Cessna just came out with a flight control mod to help minimize the problem. By the way, did you know that the C750 has such a dramatic drag rise as mach increases that at .92 it's NBAA IFR range with 8 passengers is just 750 miles; maybe that's where they came up with the C750 designation."



GVFlyer,

Some fabulous information and background on your part on the GV and BX. Also liked your comments about the 750. We know full well what you say about range at .92 mach, a coincidence with that 750 designation.

Ours may go soon. The boss dislikes the pit stops and is willing to trade the speed for range.

CitationCapt
 

GVFlyer

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As bizzarre as it may seem, General Dynamics just swapped their Citation X for an Astra!

Now, I've always thought that the Astra looked like what a Martian would render if given a verbal discription of what an Earth airplane should look like, but I guess it's a capable enough jet.

When Bombardier bought Lear from Integrated Resources the first thing they did was ask the incumbent CEO, Brian Barents, to leave. Brian found a home at Israeli Aircraft Industries. The first thing he did after arriving at IAI/Galaxy was to sell Astra's serial number 88 and 90 to the DC National Guard. This was no mean feat of salesmanship because the ROC (Required Operational Characteristics) that the Guard had written practically specified the Lear 55 and the sale of the Lears was very nearly a "done deal."

When Gulfstream bought Galaxy from IAI the first thing they did was to ask....

Brian is now on the Board at Eclipse.
 
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FL510GV

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Astra now Gulfstream?

I'll put my ignorance on a plate for you... but isn't the Astra now known as the Gulfstream 100 and the Galaxy the Gulfstream 200?, or vise-versa... anyway, GD is the parent company of Gulfstream.

Great discussion on the G-V vs Global -- of course I am biased, but every time I have seen a Global on the ramp parked next to our sleek G-V, it looks bloated and bumpy, all those tiny windows, the ugly hinges hanging off the wing... The G-V is a beautiful jet, can't say as much for the Global.
 

CitationCapt

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General Dynamics and the Astra

Funny you should mention the Astra (G100), since that is one being considered here also.
 
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GVFlyer

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Astra now Gulfstream?

Yes, you are, of course, correct. GD bought Galaxy last summer for 353 million (of which 330 mil was in cash), and another 315 million if the company meets certain revenue goals. A sweetheart of a deal for G'stream/GD in that Hyatt had 650 milllion in Galaxy.

The Astra is now the G100 and the Galaxy is the G200. I just have a hard time calling them Gulfstreams. In my view they are IAI airplanes completed and marketed by Gulfstream. The Galaxy was born needing a wing. The original concept was to have Yakovlev, serving as a risk - sharing partner, design and build the wing. Yakovlev, unable to capitalize their part of the deal, backed out in 1995. This left IAI with an order book of customers and no wing. As an expedient, they modified and enlarged the Astra SPX wing for application on the Galaxy. Voile', another underwinged, buffet limited airplane. This is no great shakes, the Galaxy is an honest airplane that does what it's supposed to at a very competitive price; it just doesn't have the margins one normally associates with Gulfstreams.

Vis-a-vis the GV's appearance versus the Global Express, which I believe, you characterized as looking like a CL604 with cancer, the GV has another fan in an unusual place. When I was taking Borge Boeskov, the former President of Boeing Business Jet and Manfred Schindler, their VP for International for their first look at a GV, Borge turned to Manfred and remarked, "If it only had to do with appearance, we would never sell another airplane, this is a beautiful jet."
 

GVFlyer

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General Dynamics and the Astra

>>Funny you should mention the Astra (G100), since that is one being considered here also.

You could do worse, it offers fair performance at a fair price and, with the acquisition by Gulfstream, at least 5 new General Dynamics Aircraft Services service centers. There are a lot of airplanes to choose from in the coast to coast at the speed of heat market. It just all depends on how much your principal wants to spend...
 
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swberry

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GVflyer, your post on the GV/GX was very well thought out and informative. This board is a pleasant change from the union web site I am accustomed to. Your information on the C750 is grossly inaccurate, however.

I do not have the cruise charts here at home, but I can tell you from alot of experience in the airplane that the range at highspeed cruise (ie: .9 to .91), FL 430, still air, full fuel and isa conditions is about 2600 to 2700 nm. slowing down to long range cruise (.82 to .84) will give you about 3000 to 3100 nm in the same conditions as above. Thsi includes reserves and with 8 pax the range numbers are not that different.

Considering the relatively small amount of difference in distance from hsc to lrc, I do not think there is a large increase in drag between the two speeds. Wing sweep (40 degrees according to my fsi manual) is one contributory factor to operating at a high mach number without a huge increase in drag. Another factor is a supercritical wing design with a shallow camber (wing shape). Both of these would delay early airflow seperation and allow a higher mcrit.

These factors do, however cause some problems with lowspeed handling characteristics, and as you stated above cessna has addressed this issue by developing a mod that has significantly improved controllability in gusty and/or crosswind conditions. Specifically, they are remixing the ratio between aileron/roll spoiler deflection. With the mod, the roll spoilers will deploy sooner based on a lesser degree of aileron deflection angle than before.

Thanks alot for the info on the GV and GX and I hope you appreciate this info on the CX from a high time CX captain...
 

GVFlyer

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Citation X

SW Berry

Thanks for your post.

I've only flown the C-750 once on a pilot demo. Coming out of the Gulfstream, which flies like a big KingAir, it was a handfull for me. I don't profess to know a lot about it, but let me remind you that the only certified data in your Airplane Flight Manual is that for takeoff and landing. The cruise data only, "has to be representative of a test article in the certification test program." This cruise data normally comes from the lowest ranking test pilot having to take a green (uncompleted) aircraft out and do hour upon hour of drag polars. This makes you the "good hands man" as a typical test point might be 37,200 ft+/- 100 and 221kts.+/- 3 kts. for 5 minutes, so you get pretty good at it after you've done a few hundred of them, but trust me it isn't worth it. Because this data is collected in uncompleted aircraft, for many manufacturers it is wildly optimistic.

Gulfstream took a Citation X in on a trade and let the flight test engineers have it for qualitative testing before it was resold (this competitive analysis is something many manufaturers do, Bombardier leased and instrumented a GV, but they were disappointed in their results; Cessna sent an Experimental Test Pilot to GV initial at FSI). The engineers ballasted the X to 8 pax and put the requisite test stations and orange wire in the jet and this is what they came up with including NBAA IFR reserves:

Normal Cruise - 0.86M Range: 2,613nm
Long Range Cruise - 0.82M Range: 2,767nm
Intermediate Cruise - 0.90M Range: 1,889nm
High Speed Cruise - 0.92M Range: 773nm
MMO - 0.93M

Takeoff distance 5,300ft.
(SL,ISA, MGTOW)

Landing distance 3,410ft.
(SL,ISA,MLW)

Initial Altitude FL 430

Direct Cost per hour: $1336.17 (GV Direct Cost is $1470.77 for comparison)


By the way, did you know that Richard Smith was the first pilot at Executive Jet to get a Citation X type rating?


Cheers





.
 
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