How To Edit an air File
Crow Horse and dbd777
This is a brief tutorial on how to edit an air file. It is not intended as a complete giude but is a guide to getting you started .
You will need the fde editor found in Utilities
I will not cover all aspects of the file, just those needed to change speed and handling.
MAKE SURE TO MAKE A COPY OF THE ORIGINAL FILE IN CASE YOU NEED TO START OVER.
When you open the fde editor you will see a list on the left side. These are the values you are going to change. Place the cursor over the value and left click it 1 time. Now it is highlighted it will also apppear in a box on the right. In the right hand Box is where you will make the changes. Once the changes have been made again left click the left side box and the change will be entered there.
This is the name of the plane as it appears in your aircraft roster.
if you change the name of the plane in the aircraft config file you may also want to change the name here too.
EXAMPLE: North American p-51d
This is the type of aircraft
Here you place the weight,wing span, power plant, and horse power. Or you can just put in, need (aircraft's name) specs here.
need p-51d specs here
Control Dimensions and placement:
Change these numbers in small amount until desired effect is achieved.
13.05000000 to 14.05000000
Do this to ailerons length / width, rudder width / length,elevator length, ailron related, and elevator related.
Set this to the same number as the number you placed in the max horsepower in the next section.
This is where you change the speed of the plane.
Cylinder Displacement Each (cubic inches)
A good way to start is to increase by 100 cubic inches at a time.
197.50000000 to 297.50000000
You can use a higher number but it is easier to overshoot the best setting.
Try increasing this number by 2.
6:0000000 to 8:0000000
This is where Cylinder Displacement and Compression Ratio come together to get your speed.
1590.0000000 to 3590.0000000
If you increase horsepower over what cylinder displacement and compression ratio can make you will not achieve the proper top end speed. So go slow.
Carb. cuts out in neg. gs:
Set this to no. You can gain speed in turns and dives by doing so.
Increase this number to 6,7,8, I have found these numbers to work best.
Flaps cycle time ( in seconds ).
Change this number in small amounts.
5.0000000 to 3.0000000
This is the time it takes to go from 0% flaps to 100% flaps. By decreasing this number you can deploy flaps fast to help in turning.
Zero fuel weight:
By reducing this you can get more speed. The less weight the more push from the engines.
Drag coefficient-zero lift:
Like the others do it in small amounts.
0.01953 to 0.00953
Leave the drag on the landing gear the same. It helps to reduce speed when landing.
Change these like the others in small amounts.
0.07324 to 0.06.324
Decreasing this helps in keeping speed in dives (on planes that are equiped with spoilers.)
If you do not want spoilers, there is a place close to the start of the file where you can check no for spoilers. If you choose no spoilers set the number to all zeros. This is done in section 327
5.01568 to 0.00000
Now your plane handles and has the speed you want, lets make it landable.
These setting will also allow the plane to stop when landing. It will also stop the bucking effect while you set on the runway and allow the plane to set at idle speed without having to hold the brake on.
You started with a zero fuel weight of (?) now the zero fuel weight is (?)
[stock] zero fuel weight: 5511
[modified] zero fuel weight: 2000
now divide the stock zero fuel weight by the modified zero fuel weight.
I have rounded off some of the numbers.
EXAMPLE: 5511 / 200 = 2.7555
2.7555 is the stock zero fuel weight to mod zero fuel weight ratio.
2.7555 = mod ratio
Main Gear Spring Loading Factor: 17972 (stock)
To get the proper MGSLF you divide the stock value by the mod ratio .
17972 / 2.755 = 6522
6522 is the MGSLF setting.
You do this same procedure with:
Main Gear Damping Factor
Main Gear Crash Velocity
Center Gear Spring Loading Factor
Center Gear Damping Factor
Center Gear Crash Velocity
Here you will set the Minimum Governed RPM and Throttle Offset Factor
Minimum Governed RPM start by reducing it by 35%
Throttle Offset Factor start by reducing it by 50%
There are some other factors you may need to change . So just remember go slow.
Alot of this will be trial and error .
If you have any questions feel free to e-mail me at: firstname.lastname@example.org
I TAKE NO RESPONSIBLITY FOR DAMGE CAUSED OR LOST DATA BY THE USE OF THIS TUTORIAL. THIS TUTORIAL IS SOLELY FOR HELPING YOU UNDERSTAND HOW AIR FILES ARE WRITTEN AND HOW THEY WORK.
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