FILE : README Ver2.txt
TITLE: FS2000 - LEARJET 45 REPLACEMENT AIR FILE - Version 2.0 Update.
DATE : Jan. 10, 2001

DESCRIPTION: This "Air" file is a replacement for the FS2000 default Learjet 45 aircraft.
It was taken from my FS98 Learjet 45 Ver. 4.0 aircraft and modified to work with the FS2000 Learjet 45.

UPDATE VERSION 2.0

This Ver 2.0 Update adjusts the Lear45.air file for better performance and handling.
The power and weight of the aircraft were adjusted so it will now climb more realistically
to FL510. After much work on the FDE, I am happy to report that this version performs with
nearly perfect fuel consumption. Most real world Learjet 45's fly at the "general purpose"
altitude of FL330, M0.76. With full fuel tanks, this yields a max range of aprox 2,000nm in still air. I used these facts as my target goal for setting up this new Lear45.air file. A
much improved Check-list is also included.

FEATURES:

1. SOLIDLY FUNCTIONAL with FS2000 parameters.
2. IAS and Mach Hold abilities.
3. 5 VERY ACURATE fuel usage profiles.
4. Aircraft SITS perfectly ON THE GROUND.
5. All FS2K "visual" model functions work, gear, flaps, etc.
6. The LEAR45.air file can be edited using ADE98, by Ian Donohoe.
7. An "EASY" on-board Check-list and fuel usage calculator method.

INSTALLATION:

To make it easy, I have included a COMPLETE aircraft folder structure for you. I did NOT include the default Learjet 45 "MODEL" and "TEXTURE" folders which must be copied from your LEAR45 folder to the LJ45-2KV2 folder. I felt doing it this way would eliminate the posibility of corrupting your default LEAR45 folder in any way and saving download time.

1. After unzipping the 2KLEARV2.zip file to a temporary folder, COPY the LJ45-2KV2
folder to your FS2000\Aircraft folder.

2. From your FS2000\Aircraft\LEAR45 folder, COPY the "MODEL" and "TEXTURE" folders to the LJ45-2KV2 folder.

3. DONE !
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NOTES: In place of the "stock" Lear 45 checklist, I have added my own. It will provide the average flight simmer with a more practical, but still quite technical "working" checklist.
Using it will take some study. It includes flight time and fuel usage calculations as well as a "ball park" step climb procedure.

Flying the "45" and EXPECTING nearly correct fuel usage is a VERY COMPLEX subject.
The MAX rated range is 2,200nm. This is almost never acheived in real life. BUT WHY?!
The Lear 45, like all planes has physical limits. A more realistic range is only 2,000nm. This is acheived with a FULL fuel load of 900 gallons, BUT can only carry 4 pax! I have set up the flight model to reflect these parameters.

Unfortunately, to date, there is only ONE WAY to set an FS2000 aircraft to have accurate fuel usage, and that is by RAISING or LOWERING the Zero Lift Drag (ZLD) of the planes FDE.

The other factors are the aircraft weight and balance, power of the engines, altitude of flight, speed and the outside air temperature or "OAT".

A realistic "all purpose" altitude for the "45" is FL330 and Mach 0.76 (450 ktas). Looking at my check list, you will notice that this gives you a range of 2,077nm. These specs were
from a test flight I made from KMIA to KLAX, a distance of 2,029nm. This works out to a
fuel economy of 2.31nm per gal. The real Lear 45 gets aprox 2.35nm per gal. Making the same
flight again at FL350, and the fuel economy goes up to 2.52nm per gal. which yields an
effective range of 2,274nm. So you can see that flying at the correct altitude is very
important if you want to fly with as much realism as possible. As the check list shows,
flying HIGHER means you must fly FASTER, if you are to maintain correct fuel economy.

FUEL USAGE CALCULATION:

The Fuel Status gauge (TC.FUELSTATUSCG.gau) by Tom Corson and Roy Chaffin were instrumental
in helping me to easily verify the validity of the FDE I was trying to develop for the new
Lear45.air file you now have with regards to giving it correct fuel usage.
To calculate fuel usage for altitudes other than for those I've listed the speeds for can
be easily done by flying up to your assigned flight altitude and adjusting your Mach speed
so the fuel usage on the fuel status gauge reads as close to 166 gph as possible and not
exceeding 175gph initially. Then, check the "Range" function of this gauge and if it is
higher than the Distance given in your GPS gauge, you should have enough fuel to make it to
your destination airport. With practice you will come to REALLY KNOW the Learjet 45. Also,
if are running "tight" on fuel and expect delays at your destination airport, just slow
down a bit and you'll make it. Keep an eye on your "range" and "gph".

AND, YOU MUST set up Flight Sim 2000 with the correct air temperature at high altitude, or your fuel usage will be LESS than it should be.

To do this:
1. Start FS2000, Click on World, Weather, Advanced Weather..., then Temp / Pressure.
2. In the Altitude box, enter a value of 45000.
3. In the Daytime temperature box, enter a value of -60.
4. Leave Day/Night variation at 5'F, Dew point at 59'F, and Pressure at Sea Level, 29.92.
5. Click the "check marks" to exit.
6. Now save a situation using your DEFAULT Learjet 45 with your other favorite settings. Also, "[X]", "Make this the default Flight" box.

Now, everytime you start Flight Sim 2000, you will be able to fly with correct fuel usage at the higher altitudes.

LEARJET 45 Weight Profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~
As you have received it, the "Lear45.air" file has the following weights:

Empty Wt + Payload = 14,000 lb (The ZFW parameter in ADE98)
Total Fuel, 900 gal = 6,000 lb.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Take-Off Weight = 20,000 lb.

The above Empty Wt + Payload reflects a pax & cargo weight of 1,000 lbs. which I feel is a
bare minimum load for this plane. MORE pax and cargo weights can be added in the
Aircraft.cfg file. The "45's" MGTOW is 20,200 lbs. For whatever extra weight you add, you must SUBTRACT that amount of weight from the amount of fuel you can load. This, of course,
reduces your effective range proportionately. 1,200 lb. is the MAX weight the Learjet 45
can carry and still carry a full fuel load of 900 gal. You will get the max range of
2,000nm at FL330 with this "profile".

THE FINAL TOUCH !

To add more realism to your flight sim experience with the Learjet 45, I HIGHLY RECOMMEND getting Rolf Buckmann's instrument panel. It also gives better frame rates! PLUS, Rolf has
made provision for you to add 3 extra "windows" that you access from a panel switch.
The files are LEARRDB.zip and LEARRDB4.zip, also available from SurClaro. Just GET IT!

CREDITS:
My most sincere thanks go out to the following:
To Microsoft for making a Great Flight Sim.
To Tom Corson and Roy Chaffin for making the fuel status gauge, without which this new
Lear45.air file would have been much harder to create.
To Ian Donohoe for the ADE98 Program we all rely on so much.

Also, my apologies to those who downloaded the first file (2KLEARV1.zip). After working on
it for a while, I realized there were just too many errors and problems with it.
Future updates will be uploaded if I can make any significant improvements. Thank you
VERY MUCH for your feedback and patience. Getting this plane to fly the way it does now has
NOT been easy!

Happy Flying! And as always, your feedback is most welcome and will always be answered. Feel free to use this "air" file in your other light jets. It is now "Public Domain". Wishing you all a VERY HAPPY NEW YEAR too.

Al Whitney - The BACAL Aircraft Lab.
alw@bestnetpc.com