ok... long explanation, so get some popcorn--
First, you need to check your BOW, as the "advertised" max range is with full fuel and 4 pax-- BUT!! Most G200s will not carry 4 pax, luggage (say 400 pounds), and full fuel and be under MTOW... so check that first with your serial number.
Second, you will be able to go max range every day of the year from a sea level, 8000 ft strip-- as long as there are no climb restrictions off of that runway-- if there are not, then yes, you can go max range every single day of the year.
However-- keep in mind that this is about a 6 and a half to 7 hour airplane... yes it has been flown longer than that, but typically this is a max 7 hour airplane. So if your winds are strong one day, you will not make it the full 3150nm you are talking about.
Cruise speeds-- A normal cruise speed is .82. You will be able to do .80 every day of the year, and long range cruise is advertised as .75-- and there are charts that show the optimal cruise speed for a given weight, plus the optimal altitude for long range cruise at a given weight... when you combine these and fly them to the letter, you will get the absolute maximum performance from the aircraft-- however! The speeds and altitudes are not very practical, so you will RARELY be able to fly them to the letter. I believe at LRC and max weight, the initial altitude is around FL330, and speed is around
.77. As you get lighter, speed comes down and altitude goes up-- ending around FL430.
The other problem you will find is SPEED vs ALTITUDE. This plane has plenty of power, and at a relative weight will outclimb a learjet-- however... if you exceed the performance charts for performance, you will get yourself into trouble VERY quickly. I know of at least 2 people that exceeded the max altitude for their given weight, stalled the aircraft, and flamed out motors... They all landed and walked away, but very lucky!!
The plane essentially has the same wing as the Astra, but is a MUCH bigger plane.. so the wing loading is significant. You MUST keep speed on the wing and NEVER exceed what your peformance chart is telling you is the max for your given weight.
For a normal flight, we use 290 to .80 for the climb, and we *never* go below .78 in the climb. If it is turbulent, we use 275 to .78 for the climb, and above 10k we *never* go below 275 kts in the climb. We rarely do max-range flights. If we do a long range flight (say to europe from the east coast of USA), we flightplan for a mach speed which never is below .76, and follow altitude guidelines to the letter.
Lengthy reply, but hope it helps. Sorry in advance for spelling and grammar, I did not proofread this before posting.
-spike