AFCAD

Version 2.0 - for FS2004
User Manual

• Changes For This Release

• 1. Installing AFCAD 2
• 2. Uninstalling
• 3. What is AFCAD?
• 4. What You Can Do With This Program
• 5. What You Will Be Able To Do With Subsequent Releases of AFCAD
• 6. Compatibility With Earlier AFCAD Files
• 7. FSUIPC
• 8. Using AFCAD and Flight Simulator Together
• 9. Starting AFCAD and Opening an Airport
• 10. Saving an Airport
• 11. Re-Opening an Airport
• 12. Deleting and Restoring Airports
• 13. Undo - The Most Important Command
• 14. Manipulating the AFCAD Display
• 15. Slewing in Flight Simulator
• 16. Lock Mode
• 17. Status Bar
• 18. Latitude / Longitude Format
• 19. Feet or Metres
• 20. Measuring Distances
• 21. Add-on Scenery and AFCAD

• 22. Anatomy of an Airport
• 23. Scenery Presentation
• 24. Selecting Objects
• 25. Moving Objects
• 26. Deleting Objects
• 27. Object Properties
• 28. Nodes, Links, and Parking
• 29. Nodes
• 30. Links
• 31. Designators
• 32. Taxiway Signs
• 33. Parking
• 34. Parking Assignments for AI Aircraft
• 35. Custom Parking Specs
• 36. Aircraft Editor
• 37. Aprons
• 38. Runways
• 39. Runway Markings
• 40. Runway Lights
• 41. VASI
• 42. Start Locations
• 43. Tower Viewpoint
• 44. Comm Frequencies & ATC
• 45. Navaids

• 46. Installing Downloaded Airports
• 47. Adding ATC to an Airport
• 48. Adding Parking to an Airport
• 49. Shifting add-on Airports
• 50. Creating Overlaid Airports
• 51. Creating a New Airport From Scratch

• 52. Fault Finder and Final Checks
• 53. Problems and Q & A
• 54. Reporting Problems
• 55. Copyright

Working with visible scenery
Previous Flight Simulator versions had two types of scenery data for airports: visible scenery and invisible facility data and maps. These two types of data were completely separate, in separate sets of files, and they had no connection. ATC and AI used the invisible facility data and knew nothing about the visible scenery, so you could have a complete airport operation set up in an empty field with AI and ATC and no visible airport. Conversely, you could have a complete visible airport that did not appear in the FS Map View or start window and had no AI or ATC. Now the same scenery data creates both visible scenery and information for AI, ATC, Map View and GPS displays.

This means that AFCAD can change some -- but not all -- visible airport scenery.  It has been given more of a WYSIWYG (What you see is what you get) format so that users can immediately see the results of changing runways, taxiways, marking, lights and other elements without having to restart FS each time.

FS2004 still accepts old BGLC format scenery files layered over the stock scenery, and in that case AFCAD will not affect the visible scenery created in BGLC, but it can still be used to alter the facility information that AI and ATC uses from the underlying stock scenery file.

AFCAD changes are no longer inserted in stock files
Unlike visible scenery which could be layered over stock scenery, facility data for FS2002 could not be properly layered. This meant that AFCAD had to insert modified facility data directly into stock facility files to replace the original data. This was a cumbersome method that required a special installer and cataloguing and backup functions to be able to remove modified airports or restore whole stock scenery files. This is no longer a problem with FS2004. An airport changed with AFCAD is now output as a separate single-airport .bgl file instead of being inserted into stock files. By default, .bgl files for modified airports are deposited in the FS Addon Scenery folder and will automatically override the corresponding stock airport when FS is next started. File distribution no longer requires export files and a special installer, the .bgl file itself can be posted and the user can copy it to the Addon Scenery folder, or another appropriate location. To remove a modified airport from the system and restore the stock airport, simply remove the .bgl file.

Consequently, the import/export and cataloguing functions have been removed from AFCAD and the AFInstaller is no longer supplied.

Mouse wheel and wheel button
AFCAD now uses the mouse wheel to quickly zoom in and out, and holding down the Ctrl key allows you to use the mouse wheel to rotate the display. Pressing the mouse wheel-button on the window allows you to grab the viewport and drag it to another location around the airport.

Parking codes
AFCAD can utilize the new parking codes feature of FS2004. This allows you to assign gates to specific airlines or other designated aircraft. Parking codes can be assigned to each gate and corresponding codes can be entered in the aircraft.cfg files for individual aircraft ‘paints’ to direct them to park at gates with the same code. Multiple codes can be assigned to a gate to specify several different airlines that can park there, in order of priority.

This means that the previous ‘Radius’ method is no longer required to configure airline parking; however, radius is still used by FS as a determining factor for which sized aircraft can fit in which parking spots.

To facilitate parking configuration, the Parking Specifications (Parking Specs) feature of the previous AFCAD has been moved from the AFCAD config file to a separate file: ParkingSpecs.txt . This file defines parking codes for airlines and other aviation groups, allowing parking to be assigned by name. A pre-defined parking specs file is provided courtesy of the Project AI (PAI) group. Thanks to Matt Fox, Graham Jackson and Jorge Buchelli and others for compiling this file. The file covers most of the world's airlines. Because airlines come and go over time, users should check the Project AI web site once or twice a year to get updated versions of this file.

Parking Labels
Labels can now be displayed on all parking spots using the new ‘Parking Types’ and ‘Parking Codes’ items under the View menu. You can also use the ‘P’ key to cycle the parking labels between Types, Codes, and off.

Aircraft Editor Tool
Available under the Tools menu, this window allows you to alter AI aircraft parameters that affect where they will park. This can be done for any of the stock or add-on aircraft models you have installed. It allows you set a parking code, parking type, and radius for an aircraft. These are the three main determinants for where an aircraft will park.

Night layout for lights
Since AFCAD can now add or modify all runway, taxiway, approach and VASI lighting, the display can be changed to a night mode to show lighting configurations. Use the ‘Show Lights’ item under the View menu. Or press the ‘L’ key to toggle this feature on or off.

NOTE: This version of AFCAD is for FS2004 ONLY. Version 1.4 works with FS2002 .

Create a folder anywhere you want and unzip AFCAD 2 to that folder. If you had previously installed the original AFCAD you could use the same folder, but AFCAD 2 does not use the same types of files so to avoid confusion you may want to clear out the folder and remove any residual files. If you want to work with both FS2002 and FS2004 then you should keep AFCAD 1 and 2 separate.

AFCAD doesn’t register itself with Windows, so if you want to get rid of it you can just delete the folder it is in and all the files.

It is a freeware CAD-style program that allows you to modify the facility data, and some of the visible scenery, used in Microsoft Flight Simulator (FS). The facility data that AFCAD works with is used by ATC to control user and AI aircraft at airports and to assign parking. It also controls the airport information that you see on the ‘map view’, GPS screen, flight planner, and start position set-up window in Flight Simulator. The visible scenery that AFCAD can modify includes runways and taxiways, and all associated markings and lights. More airport scenery and navaid elements will be added in subsequent releases.

Runways
You can add, delete, move or modify runways. This includes all runway markings, lighting, approach lights, VASI and similar visual landing aids. Although you cannot create your own runway surface textures, you can choose from an array of stock surface types from concrete to water.

Different runways for takeoffs and landings
At airports that have parallel runways, you can change which runways ATC assigns to user and AI aircraft for takeoffs and landings. Note that you cannot make ATC use crossing runways or runways at different angles simultaneously.

Taxiways
You can add, delete, move or modify taxiways. This includes taxiway markings, lighting, surface type, and designations (e.g. taxiway "B2"). In addition to the visual appearance and location of taxiways, the routing of taxiways also controls how ATC routes user and AI aircraft around the airport.

Parking
You can add parking spots (gate and ramp parking) and modify or delete existing parking spots at airports for your own use, or to increase the AI levels at an airport. Parking can be added at airports that do not currently have it. Any number of parking spots can be added. You can also adjust gate parking so that aircraft doors mate with existing boarding bridges (jetways). Parking is required in order for AI to operate at an airport, so adding parking will also allow you to program AI to use airports that do not currently have it.

Airline Gate Assignments
Microsoft added to FS2004 the capability to assign specific airlines to specific gates. You can also designate classes of aircraft to use certain classes of parking, such as GA aircraft to ramp parking, cargo aircraft to cargo parking and military aircraft to mil parking .

ATC and communications
You can add, delete, and modify communications frequencies. Adding a tower and/or ground control frequency is all that is needed to add ATC to any airport that does not already have it, you do not need an actual control tower scenery object to have ATC operation. Note that FS2002 required ATC to be present at an airport in order for AI to operate there but FS2004 no longer has that restriction, AI can now operate even at uncontrolled airports.

Start locations
Every airport comes with default start locations for your aircraft at the end of each runway. These can be changed to be at different locations, such as at the taxiway entrance to a runway.

Control tower view
The location for the control tower view of your aircraft (selected by pressing the ‘S’ key twice in FS) can be changed. This can be placed at the actual control tower location, if there is a tower, or any other location or elevation.

Shifting airports
Some third party replacement airports do not line up properly with stock Flight Simulator airports. This can cause the AI to taxi and take off and land on the grass instead of runways and taxiways. AFCAD allows you to shift the entire airport, or realign specific taxiways, runways and parking to correct this.

Note that although the taxiway modification capability is fully implemented in this release, its usefulness is limited by the inability to move or change aprons and taxiway signs. Not being able to change aprons may not seem important, but Microsoft airport designers used apron polygons extensively throughout airports wherever extra pavement was needed for such things as wide areas on taxiways, turn-around bays, enlarged fillets, etc. The ability to change aprons and taxiway signs will be added in a subsequent release.

5. What You Will Be Able To Do With Subsequent Releases of AFCAD

AFCAD is a work in progress. The ability to modify the following elements will be added to subsequent releases.

Aprons
AFCAD displays existing apron surfaces but you won't be able to create, delete, move or modify them until a subsequent release. You will also have control over the apron surface type and edge lighting.

Taxiway Signs
The ability to create, delete, move or modify taxiway signs will be added.

Navaids
Although AFCAD can currently display stock navaids and provides the functions to add, modify or delete them, no navaid changes will be saved when the airport is saved, so any changes will be lost. Subsequent releases will allow navaid changes to be saved. Note that navaid changes in FS2002 did not work with your aircraft instruments, but navaid changes with FS2004 will work with your instruments as well as appearing in the map view and GPS.

Helipads
The current version shows helipads in a basic form but you won't be able to create, delete, move or modify them until a subsequent release.

Airport structures
The capability to add, delete, or move airport structures may be added in future releases.

New airports
Currently you can only modify existing airports. Subsequent releases will allow you to create new airports from scratch.

AFCAD 2 can't use export files produced by AFCAD 1, and there will likely be no method provided to convert them for use with AFCAD 2. This is because FS2002 facility data was more simplistic than FS2004 data and FS2002 did not control any visual elements. There is no practical way to automate merging the visual elements (markings, lights, surface textures, taxiway widths, runway extensions, taxiway signs, aprons, airport structures, etc) of FS2004 airport data with the simpler FS2002 facility data. The alternative would be a manual merging process, and that would likely require as much or more work from the user to ‘fix up’ all the resulting problems than to re-do the airport from scratch.

AFCAD can be used by itself for most airport design work but placing taxiways and parking around buildings and structures can be awkward, as building are not currently displayed on AFCAD. This makes it especially difficult to mate gate parking spots with terminal boarding bridges. For that kind of work it is preferable to link AFCAD with Flight Simulator using FSUIPC. You can start Flight Simulator and ‘slew’ around an airport in a virtual aircraft and crosshairs will move on the AFCAD map to show your location. Alternatively the AFCAD map can be locked to your aircraft position like a moving map display. FSUIPC is an add-on program that, among its other uses, allows third party software to interface with Flight Simulator.

FSUIPC does not come with AFCAD but it can be downloaded from the following site:

www.schiratti.com/dowson.html

Note that FSUIPC is free to users who only need to use its basic functionality, such as linking AFCAD to FS. You only need to register and pay to use its more advanced features, which are not required for AFCAD.  AFCAD registers itself with FSUIPC when it starts up.

FSUIPC comes with documentation, but it is not necessary to read it for this application. All you have to do is copy the file FSUIPC.dll into the MODULES folder off your main Flight Simulator folder, for example:

…\FS9\MODULES

That’s all you need to do to link AFCAD with Flight Simulator.

You can start either program first. Since most people don’t have enough monitor space to have both the FS and AFCAD windows open side-by-side you can have both windows maximised, and press the Alt+Tab key to flip back and forth between them.

By default, Flight Simulator will go into pause mode whenever you leave the FS window. It can be a nuisance un-pausing that window all the time but this can be prevented by changing a Flight Simulator setting.  On the FS Settings / General window, un-check the setting ‘Pause on task switch’.

Start AFCAD and  choose Open Airport from the File menu. When this window opens for the first time AFCAD will index all the stock and add-on scenery and that may take a minute or so. When opening the window on subsequent occasions the delay will be much less.

The easiest way to open an airport is to enter the ICAO code (e.g. KLAX) in the Airport ID box and click OK. If you do not know the airport code then you can locate the city using the tree window on the left side. This lists all the cities that Flight Simulator has. All the airports associated with a selected city will be shown in the list box beside the tree window. If a city has more than one airport then you must choose the one you want to work on before closing the window.

When you open an airport, the scenery and facility data for that airport is read into memory and you should be presented with a display similar to the one below.

Any changes you make to an airport are initially done only in memory. As long as you don’t do a ‘Save’, none of the changes you make will affect Flight Simulator. If you want to experiment first before you do any serious work, then just don’t save the airport you are working on.

When you do want to save changes to the airport then click Save or Save As. A Save As window will open with a default file name assigned such as AFC_KORD.bgl, and the destination folder will default to the FS9 Addon Scenery folder. You would normally just click OK to accept the default folder and file name unless you have a specific need to change them. Note that unlike AFCAD 1, AFCAD 2 does not alter any stock FS9 files so there is no need to backup anything. If you accidentally save an airport you didn't intend to then all you have to do is delete the .bgl file that was created by AFCAD for that airport.

Assuming you deposited the file in the default Addon Scenery folder, all you have to do is start FS and go to that airport to observe the changes. If you used another folder then you may have to enable that folder in the Scenery.cfg file or using the Scenery Library window in FS.

If you have Flight Simulator open at the same time as AFCAD then after you save the airport you will have to restart FS to see the changes.

You can save your ongoing work at any time. AFCAD also does auto-backups to a separate file every couple of minutes and should recover after a failure or improper shutdown.

If you have saved an airport and you subsequently try to re-open it by entering the airport code on the Open Airport window, you will notice that the airport appears twice in the list. The entry at the top of the list will be the previously modified airport residing in the Addon Scenery folder, and the bottom entry will be the stock airport. If multiple copies of an airport exist then the list shows them ordered by scenery layer. Because the Addon folder is on a higher layer it will be the one that you will actually ‘see’ in FS. This is indicated by the stock airport in the lower layer being shown in faded print. You can open either one, but you would normally open the modified airport again if you want to make further changes.

Instead of using the Open Airport window to reopen an airport, you can just choose the airport code from the Previously Open Airports List under the File menu. That will automatically open the airport from the previously saved file in the Addon Scenery folder, not the stock airport.

Because everybody makes mistakes, the undo command is possibly the greatest invention in computer science, after the spell checker. AFCAD can undo the last 12 changes using the Ctrl+Z key, or the undo button on the tool bar. There is also a redo command, Ctrl+Y. Keep in mind that if you undo a few changes then make a new change, you will not be able to redo the changes you ‘backed over’.

Another thing to keep in mind is that not every change shows up on the map window. For example, if you changed a gate number using a Properties window, you could undo that change later on and not see anything different on the map.

Using the mouse wheel is the easiest way to manipulate the AFCAD display :

Zoom
Turning the wheel in or out will quickly zoom in or out.

Rotate
Turning the wheel with the Ctrl key pressed will rotate the display. Pressing the Shift key instead will provide a finer rotation. Note that this rotate action is disabled when AFCAD is locked to FS.

Drag
Pressing the mouse wheel-button down on the window will activate a drag cursor which allows you to drag the window viewpoint to a new location over the airport. Note that this drag action is disabled when AFCAD is locked to FS.

Tip: If you want to move the viewpoint a large distance it is usually easier to zoom out first, allowing you to move the viewpoint in one high-level drag rather than several low-level drags.

The following keys can be used to manipulate the AFCAD display if you don't have a mouse wheel. Because AFCAD can work in conjunction with Flight Simulator in ‘slew’ mode, where practical the same keys used to ‘slew’ around FS are also used to move in AFCAD.

*Shift and rotate commands don’t work in ‘Lock’ mode. In that mode you must shift and rotate the aircraft itself to move the map.

To use AFCAD in conjunction with Flight Simulator open the FS ‘Create a flight’ window and select the same airport you have open in AFCAD, pick an aircraft, and start your flight at that airport. If you have FSUIPC installed you should see red crosshairs appear on the AFCAD map where your aircraft is.

The most convenient FS mode for most airport work is in slew mode with the top down view. Press ‘Y’ to enter slew mode and Ctrl+S key to change to top-down view (both of these keys toggle in and out of those modes). In top-down view mode you will also have red crosshairs on the FS window.

If you are not already familiar with FS slew mode, you can move your aircraft all around, even through buildings and other aircraft without fear of damage. You can use the joystick to move around, but here are some other keys you may find useful in slew mode.

In slew mode, you can sometimes find you have accidentally moved so far away from the airport that you may not easily be able to get back. In that situation you can change to the AFCAD window (Ctrl+Tab) and press the ‘Home’ key on your keypad. That will return your aircraft in Flight Simulator to the Airport Reference Point, the approximate centre of the airport.

Even more useful, you can put the mouse pointer on the AFCAD map wherever you want to be, then use the right mouse button to open a pop up menu and select ‘Jump Here’. The aircraft in Flight Simulator will immediately jump to that location.

So far you have been moving the aircraft crosshairs around a fixed map. In lock mode, the crosshairs (the aircraft) will remain at the centre of the AFCAD window, and the display will move with the aircraft, similar to a GPS moving map window.

Click the lock symbol on the toolbar to toggle lock mode

Here is a map presentation using an FS aircraft aiming forward on the runway:

If you find you have slewed completely off the airport in this mode, you can press the Home key in AFCAD to return to the airport centre.

The status bar displays the Latitude and Longitude of the mouse pointer when it is moved, or the lat/long of the red aircraft crosshairs when you are slewing in Flight Simulator.

The status bar also displays the direction (rotation azimuth) of the window in degrees true. That field will also show the heading of a parking spot or start location symbol while you are rotating it.

You can enter latitude and longitude in any of the following formats without having to change any settings in the program. The degree, minute and seconds symbols ( * ’ " ) are optional.

1   N49.12345
2   N49* 15.1234’
3   N49* 15’ 45.1234"
4   N49:15.1234
5   N49:15:45.1234

You can change how the program displays latitude and longitude by opening the AFCAD.ini file and changing the following parameter line:

LatLongFormat=2

Change the number in the above instruction to the appropriate format number, 1 to 5 in the above list.

Measurement units can be changed from feet to metres for the measuring tool and all other windows that display elevations or sizes. Check the Metric line under the Tools menu. You can also select to show only parking spot sizes in metres to correlate with other utilities that display parking radiuses in metres.

You can activate a measuring tool by right-clicking on the window with the mouse and choosing Measure Distance from the pop-up menu. The distance from the point where you clicked to the current mouse location will be displayed in the status bar. You can repeat this to set a new measurement point.

This section provides information for users who want to use AFCAD to create facility information to work with add-on airport scenery from other sources, or scenery made with other tools.

Visible Model and Facility Model:

There are two types of data used to model an airport for FS.  There is the visible scenery model and the invisible facility model.

The visible model contains scenery objects such as runways, taxiways and buildings.  It is for the user to ‘see’ only, FS knows almost nothing about the airport from the visible model.

The facility model contains virtually everything that FS knows about the airport, including location name, ICAO code, comm frequencies, runway data, taxiway and parking maps, etc.  This information appears in the Map View, GPS, FS Start window and Flight Planner window. It is also used by ATC and AI to operate at an airport.  The facility model contains much of the information found in published airport facility documents.

In previous versions of FS, data for these two models were supplied in separate files that used two different formats: BGLC format for the visual model and AFD format for the facility model.  Navaid data was also duplicated in these two formats, in BGLC to produce the signals for your aircraft instruments and in AFD format for the Map View and GPS. 

Designers would use a scenery design program like FSSC or Airport for Windows to create the visible BGLC scenery and instrument-usable navaids, and they would use AFCAD to produce the invisible AFD airport facility data to match.

FS2004 introduced a new format for airport scenery. This AF2 (Airport Facilities 2) format provides facility information as before, but now also includes instructions for the visual model.  Some objects are even drawn directly from the facility data, such as drawing taxiways from the taxiway matrix. All the stock airports are created in this AF2 format, with additional legacy BGLC files for some of the airport elements. AFCAD 2 works with this new AF2 format data so you can use AFCAD to modify some of the visible airport elements as well as most of the facility data.

Replacing Stock Airports with AF2 files:

When you modify an airport with AFCAD it produces a replacement .bgl file for that airport in AF2 format.  This file has a new internal exclusion mechanism that causes it to override the stock airport, both the visual model and the facility model of that airport.  This only applies to the AF2 information that AFCAD can actually modify.  Airport information that AFCAD does not modify, such as buildings, are left to ‘poke through’ from the stock AF2 files.

With AF2 instructions you can draw a good general representation of airport elements, but because it relies heavily on a type of autogen drawing process and doesn't allow for custom textures (as far as we know), especially for pavement surfaces, it doesn't provide the flexibility that BGLC does to create high-detail airports.

Replacing Stock Airports with BGLC files:

Fortunately, FS will still accept BGLC airport scenery, so the many add-on airport scenery packages available that replace stock FS airports with high-detail visual models will still work.  

Add-on airports made with BGLC will replace all the visible airport elements, if they use the appropriate exclusion instructions,  but FS will still use the facility data from the stock AF2 airports.  Because add-on airports may not be perfectly registered with the stock airports this can result in AI not following the visible taxiways when moving around the airport, and not parking correctly at gates.

You can use AFCAD to modify the AF2 facility model so it matches the add-on airports, and add additional parking as required.

BGLC files will completely override the visual elements of AF2 data, but will not block the facility information from the AF2 files.  This happens regardless of the scenery layer the AF2 files are in.  The AF2 exclusion mechanism will override stock AF2 airports but will not have any effect on BGLC airports.  You can therefore create an AF2 replacement for a stock airport with AFCAD, and have it override the stock AF2 facility data for that airport, and in the same folder you can have a BGLC file to provide the entire visual model of the airport.

As mentioned, there are still some legacy BGLC elements used with FS2004, and one of those elements is the flattening polygon that defines the airport surface area. If this is different between a stock airport and an add-on BGLC airport then aircraft may appear to sink into the terrain.   AFCAD doesn't currently deal with airport flattening so it can't fix these problems.  It may be feasible to deal with it in a future version, but the best solution for now may be for add-on scenery designers to adapt the elevations of their scenery to the new stock airport levels or use a Flattening Switch in the Scenery.cfg file.  Elevation is not so much an issue for replacement AF2 format scenery, as it essentially just assumes the surface level of the flatting polygon.

Mixing AF2 scenery with BGLC scenery:

Some designers may be wondering if they can use visual elements from the AF2 scenery, such as runways and curved taxiways, with visual elements from BGLC, such as buildings and other structures.  It has been demonstrated that this is possible, but it involves tricky layering and exclusions methods.  This document does not provide information on how to do that and it won't until we know more about how it works, or if the process can be streamlined.  You should be able to find out more information about this on some scenery design forums as knowledge become available.

Additional Symbols:

Helipad
Localizer	Glide Path	Marker
DME	VOR	NDB

Note:  Navaids are only visible if Show Navaids is checked under the View menu.

AFCAD vs. Flight Simulator

AFCAD tries to display scenery elements like taxiways and runways so they look the same as in FS, but AFCAD does not have control of every detail of how that scenery is presented by FS. This is especially true of the taxiway network. The taxiway surfaces, junctions and curves that AFCAD presents are an illusion. What really gets saved in the .bgl file that FS reads is the ‘link and node’ network represented by the blue/green/black lines and dots. AFCAD tries to use the same rules as FS to generate a representation of taxiway, runway and apron surfaces along with other details such as surface type, markings, and lights, but the representation is not always 100% the same as FS. For this reason, although most design work can be done without having to run FS, designers should always perform a close inspection of all airport changes from within FS itself before finalizing the airport, especially if you intend to make it available to others.

Layering

This does not refer to the layering that occurs when separate scenery files overlap each other, but rather the different conceptual layers that scenery elements (runways, taxiways, etc.) occupy in the same file. FS draws scenery objects in the following order, and the order cannot be changed: Apron surfaces. Taxiway surfaces. Runway surfaces. All markings and lights. Structures. This means that if you draw a taxiway that crosses both a runway and an apron surface, the taxiway will appear to go over the apron surface and below the runway. However, the taxiway markings and lights will go on top of the runway.

Junction Surface Type

Where two or more links meet FS will automatically create a junction with fillets (curved joins) and curved markings. If the links have different surface types then FS will choose the surface type of one of the links to use for the junction surface. FS will take the surface type of the first link counter-clockwise from 270 degrees (true) as the surface type for the junction.  This rule is fixed by Flight Simulator and it cannot be changed.

An object can be selected by clicking on it with the mouse. Selected objects will turn orange.

Multiple objects can be selected at the same time by holding down the Shift key while clicking on them. To un-select an object just click on it again.

To unselect all objects just click on a blank area of the window.

Groups of objects can also be selected by dragging a ‘rubber band’ (dotted line rectangle) around the objects while holding the mouse button down. All objects inside the rectangle will be selected when the mouse button is released. You can add to your current selection by holding down the Shift key while using the rubber band.

Tip: if you rotate the window you can often make it easier to group-select objects with the rubber band rectangle. For example, if you want to select a runway and all taxi links that feed into the runway then rotate the airport so the runway is horizontal or vertical and the band rectangle can enclose the runway without spilling over other objects.

Note that taxiway segment are selected by clicking on the link lines that run down the center of the taxiway, or the connecting node dots, not the taxiway surface itself.

Any object can be selected except aprons. Apron changes will be allowed in a subsequent release.

An object can be moved by dragging it with the mouse. If multiple objects are selected and the Shift key is held down to keep them selected then all the objects will move as a group. If you move something you didn’t intend to then use Ctrl+Z to undo it. Any object can be moved except aprons. Apron changes will be allowed in a subsequent release.

An object can be deleted by selecting it with the mouse and pressing the Delete key. You can also select multiple objects and delete them at the same time. If you deleted something you didn’t intend to then use Ctrl+Z to undo it. Any object can be deleted except the Airport Reference Point and aprons. Apron changes will be allowed in a subsequent release.

Double-clicking an object with the mouse will open a window displaying the properties of that object. That window will describe everything that is known about the object, and usually all that information can be changed.

Airport Properties:

Double clicking a blank area of the window will bring up the Properties for the currently open airport. This information cannot be altered in the Properties window because it uniquely identifies the airport.

These three items are what you will be working with the most when modifying or building an airport, so controls for these have been put on the tool bar. Other objects such as runways, start locations, frequencies and navaids can be inserted or managed using menu items or properties windows.

Nodes and links form the framework for the taxiway system at an airport. FS uses an autogen-like process to expand the nodes and links to fully defined taxiway surfaces.

In addition to defining the visible taxiway layout, the node and link network defines where AI aircraft can go. AI aircraft follow this link network like slot-car toys to get from parking to the runway on departure, or from the runway to parking after landing.

There must also be a path of taxi links running down each runway so the AI can taxi on and off the runway.

The node and link network is also used by ATC to give directions to user and AI aircraft. Each link may have an associated taxiway or runway designator which ATC will read out for taxi clearance, for example "taxi to and hold short of runway 12 using taxiway B C D". The network also provides the ‘pink line’ path that you get if you request Progressive Taxi instructions.

AI aircraft will only go from parking to the runway, or the other direction, so there must always be parking for AI to work. They cannot be made to go from one part of the airport to another and stop.

Nodes are the join points for taxiway links. Nodes can exist by themselves, although they are useless in that form. Links, however, can only connect between nodes or a parking space, so taxi links can’t exist by themselves.

There are three types of nodes:

	Normal nodes are used for the vast majority of taxiway connections, including those on runways and aprons. Where taxi links join at a node there will be a taxiway junction, and FS will automatically generate the curved fillets between adjacent taxiway surfaces.
	Hold-short nodes create visible hold-short bars on the taxiway, which you can see in AFCAD if you zoom in close. AFCAD automatically orients the marker so the dashed-line side faces the runway. If for some reason the program has not oriented it the way you want then you can flip the marker to the other direction using a checkbox on the Node Properties Window.  ATC also uses these nodes as checkpoints for takeoff clearance.  Note: if hold short nodes are too far from the runway it can cause AI to freeze at the runway, see Hold Short Node Limits.
	ILS hold-short nodes also create visible markers. They are placed behind normal hold short markers on some runways to have aircraft hold further back during IMC. It does not appear that ATC or AI use this type of node for anything special.

Creating Nodes:

Select the Node Tool for the appropriate node type from the toolbar. The mouse pointer will change to a ‘node drop’ symbol.

You seldom need to create nodes by themselves, when you use the link tool it will automatically create nodes where needed as you draw links; however, if you do need to draw individual nodes then you can use a couple of methods:

You can place nodes anywhere you want by clicking on the map window while the node tool is active.

You can also drop nodes anywhere you want without leaving the Flight Simulator window by slewing to the desired location and pressing the period key ( . ) . This is easy to remember because nodes are essentially dots, like a period. AFCAD traps the period key and will place a node at that location.

Moving Nodes:

Like most objects, you can move a node by ‘grabbing’ it with the mouse and dragging it. You must be in Pointer mode to do this -- select the normal pointer from the toolbar. Note that any attached links will also be dragged and stretched with the node. Alternatively, you could bring up the properties window and alter the latitude and longitude for the node.

Deleting Nodes:

You can delete a node by selecting it and pressing the delete key. Note that any attached links will also be deleted, as links cannot exist by themselves.

Changing Node Types:

You can change the type for one or more nodes by selecting them then choosing the new node type from the toolbar. You could also use the Properties window to change the type. You can select several nodes at the same time and change them as a group.

Node Snapping:

If you create a node that touches an existing taxi link, the node will automatically snap to that link.

Overlapping Nodes:

If you try to create one node directly over another it won't be allowed. Although they can overlap to some extent, they must be far enough apart that you can identify them as two separate nodes.

Hold-Short Node Limits:

A hold-short node will not work if it is too far from the edge of the runway. That will result in ATC never giving you takeoff clearance and AI aircraft will stop at the hold-short node and get stuck there. The maximum distance seems to be just over 230 feet, but it is best to keep it under 225 feet (68.6 m) to be safe. Note that the maximum distance is from the edge of the runway, not the center line.

The program can display 225 foot radius circles around all the hold-short nodes to show the maximum allowable distance. This can be enabled by checking the Show Hold Short Limits item under the View menu, or by pressing the ‘H’ key.

Note that hold short distance limits are only crucial where AI aircraft actually enter the active runway for takeoff. AI enter a runway at the taxiway entrances closest to the ends of the runway. Hold-short nodes at other locations along the runway will not normally be used for AI entry.

This limit does not apply to ILS hold-short nodes, which are apparently not used by AI or ATC.

Another problem can occur when two or more aircraft line up at a hold-short node for departure, the aircraft at the front of the line may get clearance and proceed to take off, but the aircraft behind him may become stuck. This problem is more likely to occur with smaller aircraft. This can be prevented by placing a normal (blue) node or an ILS hold-short node just behind the hold short node. Some experimenting has shown this second node should be no more that 70 feet (21.3 m) behind the hold-short node to work with all sizes of aircraft.  As a rule of thumb, just place the nodes so they touch or overlap slightly.

Hold short nodes should only be used where taxiways enter or cross runways and not as ‘stop signs’ around the airport.

30. Links

A link connects two nodes together or connects a node to a parking spot. There are five types of links:

	Normal Taxi Links are used for most taxiways, these create taxiway segments with the width, surface (e.g. pavement), markings and lights specified in the Taxi Link Properties window. AI also follow these lines to get from parking to the runway or the other direction.
	Runway Taxi Links run down the center of runways. A taxi line is needed on a runway to guide the AI while taxiing on or off the runway. ATC will avoid routing user and AI aircraft down black taxi links while moving around the airport unless there is no other available ‘blue’ route. This keeps aircraft from using runways to taxi to position, except where transiting a runway is the only way to get to the destination.
	Apron Taxi Links have no surface texture (e.g. pavement) of their own but can have markings and lights. These are intended to be used over aprons that have their own surface textures, although you can also run normal taxi links over an apron surface if you want a separate pavement texture for the taxiway. It is unknown if apron lines have any special meaning to ATC or AI. It may be that AI avoid cutting-through aprons where they could otherwise use normal taxiways.
	Parking Connectors are similar to apron taxi links in that they have no surface texture but can have markings and lights. Parking connectors are also shown in green but you don't need to select that link type when creating them, any link that connects to a parking spot will automatically become a parking connector. Note that you can’t connect two parking spots together with a single link.
	Closed Taxi Links have the same characteristics as normal taxi links but ATC will not route user or AI aircraft down taxiways made with these links. Note that X's are not actually drawn on closed taxiways.

Normal and apron taxi links can be assigned designators such as A, B1, C, etc. (see the Designators section). The designators are used by ATC when reading out taxiing instructions.

Parking connectors always have blank designators.

Runway taxi links have designators but they are taken from the runways that the taxi links run on (e.g. "Rwy 09/27").

Runway taxi links are actually invisible and will display no marking or lights, as they are only intended to coincide with runways that have their own surface textures, markings and lights; however, runway links do have width. This can be demonstrated by moving a runway temporarily and leaving the black runway taxi links in place, as shown below. Normal taxiways that enter the runway connect to the runway taxi line, not the runway itself. 

The runway taxi line should have the same width as the runway that it mates with so the fillets that are generated where taxiways join will appear to merge onto the runway, even though they really merge onto the invisible runway taxi line.

Creating Links:

Links can be drawn between nodes that have already been drawn, or between nodes and existing parking spots. For convenience, if you try to draw a link to or from a point where there is no node, AFCAD will put a node there for you, at both ends if necessary, when you draw the link.

To draw a link, select the Link Drawing Tool for the appropriate link type from the toolbar. The mouse pointer will change to the link drawing symbol.

Put the cross on the location where you want to start the link, press the mouse button and leave it down while you pull the link line out to where you want it to end, then release the mouse button.

The characteristics of the link you are creating (surface, width, markings, lights etc) will be taken from the link it connects to, or the last link created or modified if it doesn't connect. If you want to change the characteristics you can do that from the Link Properties window after the link is created. It is often easier to draw a sequence of links first then select them all and change the properties as a group.

You can select the designator for the link (e.g. "B1") before you draw it using the list box beside the link tool button on the toolbar, but you may find it more convenient to draw the links first then set their designators later once the whole taxiway path is finalised.

Link Snapping:

If you start or end a link on an existing node, the link will snap to the center of the node.

If you start or end a link anywhere on a parking spot, the link will snap to the center of the parking spot.

If you start a link close to another existing link, the link end will snap to the existing link and a node will be placed there.

Automatic Link Splitting:

Links cannot actually have nodes in the middle of the line, nodes (or parking spots) can only be at the ends of a link. For this reason, if you connect a new link to an existing link, AFCAD will automatically break the existing link into two separate links. Although they will still look like a single line, you can treat the links separately, for example you can delete one:

If a link you are drawing crosses any nodes, it will automatically connect to those nodes, forming two or more separate line segments:

Deleting Links:

Select one or more links with the mouse and press the Delete key.

Moving Links:

Grab the link with the mouse (ensure the normal pointer mode is active) and drag it to where you want it. Note that the nodes on both ends of the link will move with it, this also applies to a parking spot at the end of a link. Any connected links will stretch

Changing Links:

You can select one or more links then choose a new link type by clicking the appropriate link tool button on the tool bar. The selected links will change to the new type.

You can select multiple links by holding down the Shift key while clicking on them, or by dragging a rubber band around them. Don't worry if other objects such as nodes or parking spot also get selected using the rubber band, they won't be affected by a link change.

You can also change a group of links by selecting them all and double-clicking on one of them. This will bring up the properties window for the link you clicked. Make sure you hold down the Shift key while double-clicking on the link to prevent the others from being un-selected. If you change one or more of the link parameters (Type, Width, Lights, etc.) the program will apply the changed parameters to all the selected links, but will not apply the unchanged parameters.

Link Properties:

Double click a link to bring up the Properties window to examine or modify the following settings:

Designator	This box has a list of all the taxiway and runway designators that are used at the current airport. You can create a new taxiway designator by typing it directly in the list box beside the Taxi Link tool on the main window, for example "B7", and pressing Enter. Runway links can only take designators for existing runways.
Link Type	You can select the link type from the Tool Bar before creating the link or you can change it afterwards. Any link connecting to a parking spot will always be a parking connector and can't be changed.
Surface	This only applies to normal and closed taxi link types. Runway, apron, and parking links do not have a visible surface so this will be ignored.
Width	Specifies the width of the taxiway surface for normal links. For runway links this should match the width of the runway, or it can be slightly smaller so there are no gaps where fillets meet the runway. For apron taxi links there is no visible surface, but this will set the spacing for the yellow edge lines and lights.
Lines and Lights	All taxi link types except runway links can have lights and yellow lines. Left and Right means the left or right side of the taxiway segment if you were standing at the node where the link was started from looking in the direction the link was drawn. Rather than try to remember what direction every link was drawn, it is usually easier to draw all the links first then select them all as a group and set the line type or lights for one edge. Then if the line or light settings are on the wrong side for any links just re-select all the ‘wrong’ links and reverse them as a group.

Unconnected Links:

It is possible for nodes and links to be touching and not actually connected. This is evident by the absence of fillets where the taxi surfaces join. This can sometimes be overlooked and it can cause considerable problems at an airport, it may even render an airport completely inoperative for AI. Be sure to run the Fault Finder tool, from the Tools menu, to point out any unconnected links.

31. Designators

There are two types of designators:

Taxiway designators, for example A, B, B2, are used with normal and apron taxiway links (blue and green links).

Runway Designators, for example "Rwy 12/30", "Rwy 26R/8L", are used only with runway taxi links (black lines).

Runway links will always have a runway designator. Taxiway and apron links can have either a taxiway designator or can be left blank. Parking Connector links are always blank.

All designators that have been created for the current airport are shown in the drop-down Designator List on the toolbar.  You can create a new designator by typing it into this box (e.g "B1") and pressing Enter.

Highlighting Designators:

When you select a designator from the drop-down list, all taxi links that have been assigned that designator will be shown in red. For example Taxiway ‘O’ in the picture below:

You can use this to verify that a taxiway is unbroken, and to verify taxiway routes match the routes in published maps of the airport you are working on.

The first entry in the designator list is always empty, and if you leave that empty entry selected then no taxiway designators will be highlighted. The second entry in the list is the word "Blank". When you select that entry, all blank designators, including all parking links, will be highlighted.

Note that if a link has an incorrect designator or is blank, that won't prevent AI from using it but ATC may give you strange or incorrect directions when you ask for taxi clearance.

Many of the stock airports have duplicate entries in the designator list, for example there may be three entries for taxiway "B" representing three different sections of taxiway B.  This is a byproduct of the tool MS used to design the stock airports and does not appear to cause a problem.  AFCAD won't allow you to enter more than one copy of the same designator.

Scanning designators:

You can flip through the entire list of designators, highlighting each taxiway path, by pressing the ‘T’ key, or flip backward by pressing Shift+T

The designator can be selected before you start drawing links, but if you are making large changes or building a new airport it may be easier to leave them blank as you create them. You can then select all the links that constitute a particular taxiway, holding down the Shift key to select more than one object at a time, then choose the designator to assign to that taxiway from the list. The selected taxiway will be shown highlighted in red after you do this. Note that you don’t have to select nodes when you assign designators, nodes don’t have designators, but it won't hurt if you do. You can also use this method to change individual links.

Runway designators are automatically assigned when you draw a runway-type taxi link on a runway so you usually don't need to set the designator for a runway-taxiway.

You can create a new taxi designator by typing it into the Designator Box on the toolbar and pressing Enter. You just need to type the designator itself, e.g. "B1", you don’t need to type the word "Taxi".

Designators are usually single letters or letter and number pairs. You can create designators up to seven characters long but ATC will spell them out phonetically. It is unknown if there any actual words that ATC will recognize as a designator. You cannot enter new runway designators, that can only be done by creating new runways.

In order to delete a designator you must open the Taxi Designators List window from the Lists menu.

Select the designator you want to delete and click the Delete button. Any links that use that designator will be changed to ‘Blank’.

The only real property that a designator has is its name. The Taxi Designators List window shows all the designator names and also shows the number of links that have been assigned each designator. If any designators have 0 links then you may have missed or misnamed a taxiway, or it may be an unused designator that you can delete.

This release of AFCAD does not show taxiway signs and cannot create, modify or move them.  That will be available in a subsequent release.

You can place any number of parking spots at an airport. Having lots of parking spots will cause no perceptible performance problems by themselves, but if you load up dozens of parking spots with AI aircraft, especially detailed add-on aircraft, you will observe a frame rate drop when you go to that airport.

You can place parking spots anywhere you want, but you must connect them to the taxiway system or it can result in AI operations becoming blocked.

Click the Parking Tool button on the toolbar. The pointer will change to a parking tool symbol. You can pre-select the parking type and parking code (airline) from the drop-down lists beside the Parking Tool button, or you can create the parking spots first and set the types and codes later.

You can use two methods to create parking:

You can place a parking spot by just clicking on the window while the parking tool is active, or if you need to precisely place parking spots in the visual scenery, at boarding bridges (jetways) for example, you can use the aircraft position on the Flight Simulator window as a reference. Slew the aircraft until it is positioned where you want to put a parking spot then press the letter ‘o’ key. This is easy to remember as the ‘o’ is a circle like a parking spot. AFCAD traps that key and will drop a parking spot at the current aircraft location and heading. The following pictures show a sequence of parking spots created by moving the aircraft around a terminal:

Note in the above picture that the parking circles overlap a certain amount. The parking circle radius is somewhat wider than the aircraft actually needs, so you can get away with a certain amount of overlap, but you should test the final product to make sure clearances are adequate with the largest AI aircraft that will use that parking.

It is usually easier to create all the parking spots first, then link them to the taxiway network afterwards. A parking spot must be linked to the taxiway network or it can result in AI operations becoming blocked.

The aircraft stick-symbol in the parking spot circle points in the direction the AI aircraft will point when it starts there. You can change the direction by selecting the parking spot symbol and grabbing the rotate handle (dot) that appears at the top of the symbol. The symbol will rotate around to follow the mouse pointer until you release the mouse button. The heading field in the status bar will show the parking direction (degrees true) while you are rotating it. You can also rotate a parking spot by changing the heading in the Parking Properties window.

If you create parking spots using the mouse-click method then the parking spots will aim to the top of the window initially and you will probably need to rotate them to the final heading. If you use the ‘o’ key method in FS to drop parking spots then they will have the aircraft heading.

Aircraft will start at a parking spot aligned with the heading of the parking circle, however, when an aircraft taxis into a parking spot it will not turn to that heading, but instead will remain at the heading of the parking connector when it stops.  If you want the aircraft to both start and stop at the same heading (essential for jetway parking) then ensure the parking connector is in-line with the aircraft symbol.  This may require inserting a node close behind the parking spot to allow the aircraft to turn to the desired final heading.

Select one or more parking spots with the mouse and press the Delete key.

To change the parking type, select one or more parking spots then choose an entry from the Parking Types drop-down list on the tool bar. All the selected parking spots will change to the new type and will get the default radius for the new type.

To add a parking code, select one or more parking spots then choose an entry from the Parking Codes drop-down list on the tool bar. All the selected parking spots will get the new code. If a spot already has a code then it will get a second code, and so on. To delete all codes for selected parking spots, choose the blank entry at the top of the Parking Codes list.

You can select multiple parking spots by holding down the Shift key while clicking on them, or by dragging a rubber band around them. Don't worry if other objects such as nodes or links also get selected using the rubber band, they won't be affected by a parking change.

You can also change a group of parking spots by selecting them all then double-clicking on one of them. Hold down the Shift key while doing this to prevent the other spots from being un-selected . This will bring up the properties window for the parking spot you clicked. If you change one or more parameters (Radius, Area, Parking Codes, etc.) the program will apply the changed parameters to all the selected parking spots, but will not apply the unchanged parameters. For example, if you want to change all the parking spots surrounding Terminal A to be designated as "Gate A xx", where xx is the existing gate number, then use this procedure:

1. Select all the parking spots around Terminal A.
2. Double-click on one of them while holding down the Shift key.
3. Select "Gate A" on the properties window.
4. Click OK to close the window.

Double click a parking spot to bring up the Properties window to examine or modify the following settings:

The Parking List window, called from the Lists menu, shows all the parking spots for the current airport as they will appear in the Start Positions list on the Flight Simulator Create a Flight window.  The radius and any assigned parking codes are also shown.

One of the criteria FS uses for AI parking assignment is the order of the Parking List (see Parking Assignments for AI Aircraft). You can reorder the parking list by grabbing list entries with the mouse and dragging them to different locations in the list. You can also use the Randomize button to mix up the spots.  This will prevent AI from bunching up in sequential gates.  The Randomise button will keep parking grouped by type (gate, ramp, cargo), but will mix-up the order of the parking spots within each type-group.

You can click on the column headings of the list to sort it by area, type, size, etc. This makes it easier to locate parking spots in a large group, or to inventory parking. Keep in mind that when you close the window the order you see in the list will be the order the parking will appear in Flight Simulator, so if you sorted parking then you should randomize it again before you exit. Alternatively, you can click the Original Order button, which will return the parking list to the order it was in when the window was opened.  If you accidentally re-ordered parking then press Ctrl+Z after you close the window to undo it.

You can connect more than one link to a parking spot to create ‘drive through’ type parking; however, because of limitations with the AI it rarely results in the kind of behaviour one would hope for, that is, aircraft driving in from one side and driving out the other. AI will take the shortest path to the active runway and even if they can exit a parking spot going forward they will go out the rear taxi path, if that is the shortest route to the runway. You should also be careful to avoid serial or ‘string of pearls’ parking, which can block some parking spots when others are occupied.

Microsoft sprinkled parking rather loosely around the stock airports. Not surprising as they had to do this by hand for a few thousand airfields. You may want to delete most or all of the parking spots at an airport before you create your own so you aren’t constrained by existing parking spots.

When you choose an aircraft to slew around in, use the same type of aircraft you are creating parking spots for to get an idea of the size requirement and clearances. This is especially important if you want to mate aircraft doors with boarding bridges (jetways).

If you are trying to align an aircraft with a boarding bridge you may find the FS slew keys, especially the arrow keys and rotate keys (keypad 1 and 3) provide finer control than the joystick.

Avoid trapping AI aircraft in pockets, such as behind other parking spaces, as an AI aircraft may become stalled if another aircraft is parked it its way.

Ensure all parking spots are connected to the taxiway system. An unconnected parking spot will lock out other parking spots further down the parking list, even if they are properly connected. Run the Fault Finder from the Tools menu to check for unconnected parking spots.

Flight Simulator permits assigning airlines and other aviation groups to use specific parking spots at an airport.  It also allows assigning general classes of aircraft such as cargo, GA, and military to parking spots.  And although it doesn't directly allow you to assign specific aircraft models such as 737s to specific parking spots, you can designate parking spots to be used by certain sizes of aircraft. This section deals with the rules and parameters used to make the AI park where you want at an airport.

FS uses the following criteria to decide where to park an AI aircraft.  These criteria are in order from most important to least important:

1. Parking Codes   (KLM, AAL, etc.)
2. Parking Types   (Gate, Ramp, Cargo, etc.)
3. Parking Areas   ( Parking, Gate 1, Gate A 1)
4. Parking Radius   (31m, 38m, etc.)
5. Parking List order  (first, second, third parking spots listed etc).

The lower level criteria are only used as tie-breakers if there are two or more parking spots that meet the higher criteria, otherwise the lower level criteria do not come into play.

It may seem like there are a lot of criteria and rules to deal with in order to make aircraft park where you want, but in general you would: use Parking Types and Parking Areas to section off the main parts of the airport, use Parking Codes to establish which airlines go where, and use the Parking List to establish the order of assignment. Knowledgeable users who really want to fine-tune an airport can also adjust radius settings to narrowly define which aircraft models can park at which gates, but that isn't essential.

Parking codes are the most important factor in assigning parking. Each parking spot can be assigned one or more codes, and each separate aircraft version, or ‘paint’, can be assigned a code. These codes have no special meaning to FS, it just tries to match the aircraft codes with the parking codes to slot aircraft into specific parking.  Since the codes have no special meaning you could use any set of characters, but it is best to use ICAO codes where possible when assigning parking for airlines and other aviation groups in order to maintain consistency with other designers of flight sim add-ons.  Every airline has a unique ICAO code, such as AAL, for American Airlines.

An AAL-coded aircraft will park in an AAL-coded parking spot if there are any available, as indicated by the "1st choice" in the picture below.   Parking spots can have several codes for situations where several airlines can use the same gate, so if there are no empty parking spots with AAL as the first code then it will use a spot with AAL as the second code, as indicated by "2nd choice" in the picture.  If there are no empty parking spots with code AAL at all, then it will park in a spot with no codes, as indicated by the "3rd choice".

If there are no uncoded spots then it will park in a spot belonging to someone else, as indicated by the "4th choice".   This last tendency can cause problems.  If an airline has more flights arriving at an airport than there is available parking for that airline then an overflow situation will occur and airlines will park in other airline's parking spots. This will cascade until hardly anyone is parking at their own gates.  The best solution for this is to schedule AI flights carefully so this doesn't happen; however, at larger airports this can be nearly impossible so the next best solution is to provide numerous uncoded parking spots on empty areas of pavement around the airport, away from the terminal buildings.  Since an aircraft will park in an uncoded spot before parking in a spot with the wrong code, any overflow aircraft will go to these ‘holding pens’ before taking up a gate where it shouldn't be.  Unfortunately, aircraft will not proceed from the holding pens to gates when a gate becomes available. 

A Parking Specs file has been provided, courtesy of the Project AI group, that contains the ICAO codes for most of the world's airlines, listed by airline name. You can select codes from that file using a drop-down list on the toolbar. The same list is also on the Parking Properties window and the Aircraft Editor. You can customise the Parking Specs file to add your own airlines or other special-purpose codes.  

You can also type or paste codes directly into the codes box if you want to insert a new code without bothering to modify the Parking Specs file. 

For aircraft, parking codes are designated by inserting a line such as "atc_parking_codes=AAL" in the aircraft.cfg file, but you can use the Aircraft Editor window under the Tools menu to insert codes for aircraft without having to hand-edit files.

Codes are not limited to airlines, you can use them to assign business jet parking, flying school parking, or military unit parking, as just a few examples.  The Parking Specs file has a few pre-defined generic military and GA classes (beginning with ‘Military’ and ‘GA’), but can also make up your own codes such as "F-16" or "C-17" for example.

A parking code can be any combination of letters and numbers up to four characters long.  Other characters such as punctuation can also be used. FS itself has no restrictions on such special characters, but there may be other third-party tools in the future that use special characters for other purposes so use them with caution.

None of the FS airports or aircraft have parking codes assigned by default so you don't have to worry about conflicting with existing codes.

Note that parking codes are used for AI only and FS will not use codes to designate parking for user aircraft.

The parking type is used as a criteria only in cases where parking codes are not used or where there is more than one available coded parking spot that is equally good. For example, several AAL parking spots available for an AAL aircraft.  The table below shows the parking spot types and the matching aircraft parking types:

FS accepts only the parking types shown in the list above, you cannot add more or rename them. 

Size words such as "Heavy" in "Gate Heavy" mean nothing as far as parking assignment goes, all that really matters is that an aircraft tagged for "Gate" parking finds a parking spot of any "Gate" type.  Similarly, the word "GA" in "Ramp GA Large" does not limit a spot to General Aviation aircraft, all that matters is an aircraft tagged for "Ramp" parking finds a parking spot of any "Ramp" type.  This could be a commercial  DeHavilland Dash 8 for example.

You can specify the type for a parking spot using the drop-down list on the toolbar or an equivalent list on the Parking Properties window.  For an aircraft, parking types are designated by inserting a line such as "atc_parking_types=GATE" in the aircraft.cfg file, but you can use the Aircraft Editor window under the Tools menu to insert parking types for aircraft without having to hand-edit files.

You can assign multiple choices for aircraft parking types, such as Gate, Ramp, Cargo, but if you use parking codes as the primary method for parking assignment then it may be less confusing to just assign one parking type per aircraft.

FS has some of the stock aircraft designated with parking types already, such as cargo aircraft designated for Cargo type parking. If you do not use parking codes for AI assignment then this is a good way to ensure that classes of aircraft at least go to the right areas of the airport. For aircraft with no designated parking type, FS by default assigns aircraft with an "atc_airline=" tag in the aircraft.cfg file to gate parking, and all others to ramp parking.  You can use the Aircraft Editor to check for an ATC Airline tag.

If two or more parking spots meet all the above criteria then FS will assign an aircraft with an "atc_airline=" tag (an airline callsign) in the aircraft.cfg file to a parking area designated as "Gate", and will assign an aircraft without a airline tag to an area designated as "Parking" in preference to other areas.  This is a way FS uses to funnel GA (non-commercial) aircraft to general ramp parking for the stock AI.  You can check and modify the "atc_airline=" using the Aircraft Editor window. 

FS will also assign airline aircraft to a parking area designated as "Gate" in preference to a parking area designated as "Gate X", where X is a letter.  For example, it will assign "Gate 32" over "Gate A 32".  The order of gate letters or number does not appear to be important, so "Gate A 1" is not necessarily preferred over "Gate B 3".    If you are creating parking for an airport terminal then it is best to use all "Gate" areas or all "Gate A, B, C, etc" areas, unless you have a particular reason for AI to prefer one area over others.

Radius is one of the least important criteria for parking, but if all the above criteria are equal then FS will assign aircraft to the parking spot that is closest to the aircraft radius; however, it is important to note that  FS will not assign an aircraft to a parking spot that has a smaller radius than the aircraft.  In other words, it won't try to jam a big aircraft into a small spot.  That rule takes priority over all others.

Each parking type has a default radius, for example the "Gate Small" type has a default radius of 31m.  The radius, however, is not fixed to the parking type so you can set it to any value you want.  Although there is no way to direct specific aircraft models like 737s to specific parking spots, you can use the radius to narrowly define the size of aircraft that can park in particular spots. The default radius values are adequate for classifying aircraft by size for all but the most 'fine tuned' airports, so adjusting the parking and aircraft radius is not recommended for inexperienced users.

Each aircraft model has a designated radius. The aircraft radius is not the exact size of the aircraft, but is instead a larger ‘protective bubble’ around the aircraft.  It determines how far apart AI aircraft will be separated when lining up for takeoff, and it is used to determine the pushback distance, and it likely has other uses in FS as well.

In order to customise parking for aircraft models you would generally adjust the radius of the parking spots themselves but you may also need to adjust the radius of aircraft models to ensure all aircraft of a similar size actually use a common radius.  You can adjust the parking spot radius using a box on the Parking Properties window, and you can adjust the aircraft radius using a box on the Aircraft Editor window, under the Tools menu.  Note that since aircraft radius is used for more than just parking you can't move it too far either direction, but a few metres either way is usually safe.  The aircraft radius is embedded in the aircraft's .mdl file, and there is usually only one radius value for an aircraft model, not one for each separate aircraft version or ‘paint’, so adjusting the radius for one paint will adjust for all paints that use that same model.

Note that aircraft radius is always specified in whole-number metres, so to prevent confusion it is best to set the parking radius units to metres as well (under the Tools menu).   

Older add-on aircraft built before FS2002 used a different type of .mdl file which does not have the parking radius encoded. For those aircraft, Flight Simulator applies a default parking radius of 16 metres and that value can't be changed. This can result in older add-on aircraft parking in inappropriate sized spots.

If more than one parking spot meets all the above criteria then FS will assign aircraft to parking spots in the order they occur in the Parking List window.  You may think this criteria is so low that it is not important, but in reality this is a significant factor because most terminals will have several parking spots of the same size and type designated for the same airline, so FS will ultimately have to choose between them based on order.  If parking spots are all ordered by gate number it may look more orderly, but aircraft will also be assigned parking in gate number sequence, which is not realistic.  For that reason it is best to rearrange or randomise gate numbers in order to prevent AI from bunching at one terminal or in one area of a terminal.  You can drag parking entries around the Parking List window or use the Randomise button on that window to so this.  The Randomise button will keep parking grouped by type (gate, ramp, cargo), but will mix-up the order of the parking spots within each type-group.

The FS parking assignment mechanism provides for considerable flexibility so there are different ways of doing things, for example using IATA codes instead of ICAO codes; however, airport and aircraft designers should all use the same standard methods, where possible, so add-on airports and AI aircraft from different sources will work together seamlessly for the end user.  If designers all ‘go their own way’ then it will result in confusion and endless tweaking and reworking for the users who download their work.  The Project AI group and associates have considerable experience creating real-world airline liveries for AI and making them use gates realistically in FS.  They have come up with methods and standards that, although maybe not perfect for every situation, work well and can be applied by all designers. Anyone who plans to create airport parking, especially for public use,  should visit the following site and pick up the document FS2004Parking.html , and any other associated material:

afcad.projectai.com     or     www.ProjectAI.com

The ProjectAI site also has forums where considerable expertise can be tapped for assistance with AI and airport design problems.

AFCAD comes with a Parking Specs (Specifications) file containing most of the worlds airlines and their ICAO codes.  This also defines the colours displayed on parking spots in the AFCAD window.  You can customise this file in various ways, for example to add a new airline, or change an existing one, or change the colour for an airline's parking, or to create a parking spec that assigns several codes together. The file is named ParkingSpecs.txt, and you can edit it with Notepad.  Here is the format of a file entry:

    Spec_Name,R,G,B,Code

for example:

    Air Canada,252,215,136,ACA

You can add comments to the file by preceding them with a semicolon ( ; ) and you can add extra blank lines and spaces wherever it would help to improve clarity.

New entries don't have to be inserted in alphabetical order, but the list will be preseneted in the order given so it makes searching less confusing if entries are in alphabetical order.

You can assign any colour you want to a parking spec using RGB colour values. An RGB colour is a set of three comma-separated numbers that range from 0 to 255, for example "0,0,0" for black and " 255,255,255 " for white. You can use the Windows ‘Paint’ application to experiment with colours and to determine RGB values. Open the Edit Colours window from Paint's Colours menu and select Define Custom Colour.

The Aircraft Editor window, called from the Tools menu, allows you to adjust all the parking related parameters for aircraft you have installed.  These parameters are stored in the aircraft.cfg files and .mdl files. Here are the controls on that window:

If you want to adjust several aircraft in sequence on this window you can make the required changes and select the next aircraft in the list without having to close and re-open the window again.

Before AFCAD changes the aircraft.cfg or .mdl file it makes backups of those files. If you want to restore the original settings for a particular aircraft just click the ‘Restore Original Settings’ button and it will restore the settings from the backup files.

Aprons are the large expanses of concrete or other material that aircraft park on.  Apron surfaces are also used in stock FS airports anywhere an extra piece of pavement is needed around the airport, such as to widen a taxiway  to form a waiting area, or turn-around bays on runways.

This release of AFCAD shows all the apron surfaces at airports but cannot modify or move them or create new apron surfaces.  That will be available in a subsequent release.

You can drag them with the mouse, or open the Runway Properties window and change the latitude and longitude.

This can only be done by opening the Runway Properties window and changing the heading field.  The heading is in degrees true.

Call up the Runway window from the Insert Menu. You must then fill in the properties for the new runway. You will probably want the published data for the airport you are working on to help you with this. At a minimum you will have to enter the length and width.

Select it with the mouse and press the Delete key. A runway may have associated ILS equipment (localizer, glide path and DME) for both ends, and if you delete that runway then any associated ILS equipment will also be deleted.

Double click a runway to bring up the Runway Properties window to examine or modify the following settings.  Also see Runway Markings, Runway Lights, and VASI.

You can call up a list of all runways from the Lists menu. As with the Parking List, you can re-order the runways by dragging the list entries around with the mouse. This only affects the order the runways are listed on the FS airport description window on the map view.

The rules which FS uses to enforce runway closures are not yet fully understood, but a few things are known:  Runway closures only appear to work with parallel, or very nearly parallel runways.  You can close any combination of parallel  runways for landing and/or takeoffs, as long as there is at least one runway open for landing and one open for takeoffs.  Takeoffs and landing must be in the same direction.  If you try to use closures to force takeoffs and landings to occur in different directions, or if you try to force takeoffs or landings in an unfavourable wind direction then ATC may override the closures and use the runways it prefers anyway.

The rules which FS ATC uses to decide which runways to make active are not fully understood, but here a few things we know:

ATC can use two or more runways at a time for takeoff and landings, but they must be parallel. It won't use crossing runways.  This is no doubt to avoid the complexities of keeping crossing arrival and departure aircraft streams separated, both on the runways and the approaches.

When two separate runways are in use, ATC will not divide the load evenly between them, but instead it will assign the runway closest to the direction the aircraft is arriving from.  So at an airport with parallel East/West runways, all traffic arriving from the North will land on the northernmost runways, and all traffic from the South will land on the southernmost runways(s).  This is also, no doubt, to prevent separation problems with crossing arrival/departure streams.

Propeller aircraft are often directed to shorter runways than jet aircraft.  This seems to be keyed to the engine type field in the .air files.

New Runways and Airport Terrain:

If you create a new runway for a stock airport then you may find the runway is outside the ‘flat’ area of the airport and parts of the terrain stick up through the runway, or it is underground or floating in air.  This version of AFCAD can't adjust the airport area polygon (flat area) but future versions may be able to do that.  In the mean time, you can correct this either by putting a Flattening Switch in the scenery.cfg file, or create a small .bgl with a flattening polygon encompassing the new runway.  FSSC or another scenery design tool can be used to produce such a flattening polygon.

Runway markings are set on the Markings tab page of the Runway Properties window.  Here is a picture describing the markings options:

The Precision Runway setting causes the centerline to be drawn wider and the last 2000 ft of edge lights to be yellow.

The Closed Mark (X) setting draws an X in place of threshold stripes, but does not actually close the runway to AI.  Note that FAA rules state that a runway can't be closed just at one end, it must be closed at both ends, which would require both the base and reciprocol Closed Marks to be checked. This may also apply in other countries. 

The STOL Marking draws "STOL" (Short Takeoff and Landing) in place of the threshold stripes.

Some markings are not enabled on very short runways.

Runway lights are set on the Lights tab page of the Runway Properties window.  Lights are displayed on the AFCAD window when you select Show Lights under the View menu, or toggled on by pressing the L key. Here is a picture describing the Light options:

Approach Strobes are a line of ‘running’ strobes in front of some approach light systems (ODALS, MALSF, SSALF, etc).  This sets the number of strobes in the sequence.

Edge Lights are yellow for the last 2000 ft when the Precision Runway setting is checked on the Markings tab page.

Visual approach slope indicators are set on the VASI tab page of the Runway Properties window.  VASI systems are displayed on the AFCAD window when you select Show Lights under the View menu, or toggled on with the L key. Here is a picture describing the VASI options:

Note that VASI are normally installed on the left side (the pilot's side) of the runway, at the touchdown point.  Some systems such as VASI 12 and VASI 16 have lights on both sides.

On the Flight Simulator window where you choose the starting airport for a flight, you have a list called ‘Runways/Starting Positions’. You can usually start at either end of any runway. At the bottom of that list you have all the parking spots, as described in the Parking section. The runway start locations don’t have to be at the exact ends of the runways, you can change the position and heading of each start location, and even add more. However, there should be a start location assigned for every runway (e.g. for both runways 08 and 26 for a runway 8/26 pair). The Active runway category on the start locations list will look for one for the active runway, and if FS doesn’t find one it could cause problems. Run the Fault Finder from the Tools menu to check that runways have matching and properly designated start locations.

By default, they aren’t displayed in AFCAD so as not to clutter up the runways. You can display them by choosing Show Start Locations from the View menu or by pressing the ‘S’ key. They appear as pink circles.

You can drag them anywhere with the mouse, for example, if you want to start at the hold-short marker at the taxiway entrance to the runway.

You can change the start heading the same way you do with parking spots. That is done by selecting the start location symbol and grabbing the rotate handle (dot) that appears at the top of the symbol. The symbol will rotate around to follow the mouse pointer until you release the mouse button.  You can also change the heading in the Start Location Properties window.

Call up the Start Location window from the Insert Menu. You can fill in the properties for the new start location, or just click on a runway at the location where you want to start and the properties will be filled in for you. Note that the start location must be designated with a runway number (e.g. 16, 9R etc.) but that runway doesn’t have to actually exist.

Select one or more with the mouse and press the Delete key.

Double-click on a start location to open a Properties window. The parameters are straight-forward.

You can call up a list of all start locations under the Lists menu. You can re-order the start locations by dragging the list entries around with the mouse.

This doesn’t create a visible control tower object, and it has nothing to do with ATC in Flight Simulator. It specifies where the default tower viewpoint of your aircraft will be. You can see your aircraft from the tower view by pressing the ‘S’ key in Flight Simulator. You can put this viewpoint anywhere you want. It can be where the real tower is, or it can be at any other location and elevation. The tower location is shown with a pink circle on the AFCAD map:

If a tower location is not specified for an airport then FS will place it at some default position near your aircraft starting position. There can be only one tower view at an airport, regardless of how many tower scenery objects the airport may have.

You can drag it anywhere with the mouse.

Call up the Tower Viewpoint window from the Insert Menu.

Select it with the mouse and press the Delete key.

Double-click on the tower symbol to open a Properties window.

Communication (comm) frequencies are not visible on the AFCAD map, but you can set up all the radio channels (tower, ground, ATIS, clearance delivery, etc.) for an airport using AFCAD. These frequencies are shown on the Flight Simulator map view window when you click on an airport to get information for it. They can also be tuned with your aircraft radio stack. But most important of all, comm frequencies enable ATC.

To make ATC work at an airport that doesn’t currently have it, all you have to do is add a control tower frequency and you will get full ATC service at your airport. It is as simple as that. This works even if there is no visible control tower object at that airport, or a control tower there in real life.

You can call up a list of frequencies already at your airport (if any) using the Comm Frequencies item under the Lists menu..

Click the ‘Insert’ button on the frequencies list window. You will be provided a window to fill in the properties for a new radio channel.

Use the Comm Properties window to examine or modify the following settings:

Select the frequency in the list and click the Delete button.

IMPORTANT NOTE: This version of AFCAD allows you to examine navaids, BUT ANY NAVAID CHANGES WILL NOT BE SAVED WHEN YOU SAVE THE AIRPORT.  The ability to modify and save navaids will be added in a future release.

AFCAD can show all navaids that are associated with an airport. When you display an airport in AFCAD you can see all the ILS equipment: localizer, glide paths, DMEs, markers, NDBs and  VORs associated with that airport and its ILS approaches.  However, AFCAD can't open enroute VOR and NDBs that are not associated with airports.

When working with ILS equipment keep in mind that the localiser (long green arrow) is actually located at the far end of the runway from where you will be landing. Most published airport charts for pilots show the localizer symbol at the approach end, so as not to obscure the runway symbol, but AFCAD shows it at the true location. The glide path (small green arrow) for that approach is located near the touchdown point at the other end of the runway. The DME (blue square) may be located at either site, or somewhere else.

You may also find some airports have offset localisers, which don’t line up with the runway for various reasons such as terrain avoidance and noise abatement.

By default, navaids aren’t displayed in AFCAD so as not to clutter up the runways. You can display them by choosing Show Navaids from the View menu, or toggle them by pressing the ‘N’ key.

You can drag them with the mouse, or open the Properties window for the navaid and change the latitude, longitude and heading (if applicable).

Call up the window to create the appropriate navaid (Localiser, Glide Path, Marker, etc.) from the Insert Menu. You must then fill in the properties for the new navaid. You will probably want the published data for the airport you are working on to help you with this.  If you are adding a new ILS then the program will initially place the localiser and glide path units where they would typically be for the chosen runway, but you can move them later.

Select it with the mouse and press the Delete key.

Double-click on a navaid to open a Properties window. The navaid parameters are mostly self explanatory. You can consult aviation charts and publication to fill in most of the blanks.

You can call up a list of all navaids at a site under the Lists menu. The ILS equipment is grouped by runway end, except markers which are grouped together at the end of the list.

Navaids and ATC / AI :

The AI aircraft do not use VOR, NDB, and DME information, and they do not appear to use ILS systems for guidance, but ATC may use the presence or absence of an ILS to decide on runway assignments under some conditions.

If you downloaded an AFCAD airport file that someone else created and you want to install it, the author may have included installation instructions or even a self-installer. If he didn't then you can install an airport file by simply copying the .bgl file to the following folder and restarting Flight Simulator:

 .../FS9/Addon Scenery/Scenery/

To remove an AFCAD airport, just remove the file from that folder.

If all you want to do is add ATC to an airport then you don’t have to read this entire document. To add ATC you only need to add a tower frequency, you don’t need an actual control tower. You should refer to the section Comm Frequencies & ATC for details, but here are the instructions in a nutshell:

1. Start AFCAD.
2. Call the Open Airport window from the File menu and enter the airport you want to work on in the Airport ID box, for example CYYF.
3. Open the Comm Frequencies list window, under the Lists menu.
4. Click the Insert button on that window, a new window will open.
5. Enter the name of the airport or town in the Name box, for example "Penticton".
6. Leave the Type box set to ‘Tower’. A random frequency will be assigned for you (e.g. 118.3), or you can enter your own or use the real tower frequency if your airport has one.
7. Click OK to close the window.
8. From the File menu, save the airport and exit AFCAD.
9. You can now run Flight Simulator and you will have full tower service at that airport.
10. If you want to have a more sophisticated tower emulation, you could also add an ATIS frequency and maybe a separate Ground frequency. For ATIS, use the airport ICAO identifier instead of the airport name (for example, KLAX).

If you just want to add a few extra parking spots and they don’t have to be precisely aligned with any scenery features, such as boarding bridges (jetways), then you can probably do that with just the mouse and you don’t need FSUIPC. If your parking does require precise placement then you should do that from within Flight Simulator itself, using FSUIPC to tie your virtual aircraft position to the AFCAD display. FSUIPC must be installed separately, see the FSUIPC section.

After you create parking spots you must link them to the taxiway system or they won't be of any use and may interfere with AI operation. You should have a basic familiarity with the node and link system for taxiways. If you are extensively reworking an airport then you should carefully read the sections of this manual up to the Parking section. If you are just adding a few parking spots then you could probably get away with skimming the sections on nodes, links and parking. Here is a typical procedure for adding parking in a nutshell:

1. Start AFCAD.
2. Call the Open Airport window from the File menu and enter the airport you want to work on in the Airport ID box, for example CYOW.
3. If the existing parking spots are not to your liking, or they would get in the way of your new parking then you may want to just delete them by selecting them and pressing the Delete key. You could also drag the existing parking spots to more favourable locations with the mouse.
4. If you have FSUIPC installed then you can start Flight Simulator and go to the airport you are working on.
5. In Flight Simulator, go into slew mode (Y key) and the top-down view (Ctrl+S).
6. Choose the type of parking you want to create (e.g. Gate Medium) from the Parking Types drop-down list on the AFCAD toolbar. You can change the parking type later if you need to. Make sure the Parking Tool is active (the green circle button on the toolbar is depressed).
7. If you are using Flight Simulator then slew to the location where you want to place a parking spot, get your aircraft in the position and heading you want for the parking spot, then press the letter ‘o’ key on the FS window to create the parking spot.  Repeat this everywhere you want a new parking spot. If you are not using Flight Simulator then just click with the mouse on the AFCAD display where you want a parking spot and use the mouse to rotate it after you create it.
8. When you have the parking spots placed where you want them then you can assign gate numbers, for example "Gate 14" by double-clicking on each parking spot and selecting setting the appropriate gate or parking number in the Properties window.  All parking at a terminal should be labelled "Gate" or "Gate X"  and not "Parking".
9. You can assign parking spots to specific airlines by first selecting all the parking spots you want  assigned to a particular airline, then choose that airline from the drop-down list on the toolbar.  The parking code for that airline will appear beside the selected parking spots.  You can also do this with the Parking Properties window, which has the added feature of allowing you to enter airline codes that may not be in the parking codes list.  You can also assign multiple airlines to use the same parking spots.
10. You may also want to open the Parking List window, under the Lists menu, and randomise the parking spot order using either the Randomise button or by dragging the list items around with the mouse. This will prevent the AI from bunching up in one area of the airport, which  can occur because AI is assigned parking based on the order of this list.
11. Return to the AFCAD window and choose the Apron Link Tool (button with green line) from the toolbar.
12. Link all the parking spots to the nearest taxiways by dragging links from the parking circles to the taxiways, or from the taxiways to the circles.
13. If you are creating parking spots for AI use and they are assigned to specific airlines, then you may also want to create overflow parking spots wherever there is some empty pavement around the airport.  This will prevent airlines from spilling over to parking spots belonging to other airlines when there is not enough of their own parking. Do not assign parking codes to these overflow spots.  An aircraft will use a parking spot with no parking code before it uses a parking spot with the wrong code, so overflow aircraft will park at these overflow spots away from the terminal rather than at the wrong terminal gates.
14. When you have finished making changes, run the Fault Finder from the Tools menu to check for problems such as unconnected links.
15. Save the airport and exit AFCAD.
16. You can now run Flight Simulator and test the parking spots, either by starting in those parking spots yourself or creating AI flight plans to use them.

The visual models of some add-on airports are not in the exact same locations as the stock Flight Simulator airports, with the result that the AI aircraft taxi in the wrong places and take off and land in the grass instead of  the runways. When you use add-on airports to provide the visual model for the airport then the stock FS airport only provides the invisible facility data such as the taxiway routing maps that AI and ATC use to navigate at an airport.

AFCAD can shift the facility maps so they line up properly with the visual models, and make other fine adjustments to taxiways. Note that AFCAD currently provides no method to make the elevations of add-on airports match the Flight Simulator ground level for an airport, so it won't fix problems of AI aircraft wheels being above or below ground level.  Since the add-on airport provides all the visual information it also doesn't matter if AFCAD can't move aprons and structures for the stock airports, as they will not be seen.

Here are the basic instructions to improve visual and facility airport registration. The process will be easier if you have FSUIPC installed, see the FSUIPC section.  

1. Start AFCAD.
2. Call the Open Airport window from the File menu and enter the airport you want to work on in the Airport ID box, for example KDEN.
3. If you have FSUIPC installed then start Flight Simulator and go to the airport you want to work on.
4. In FS, go into slew mode (Y key) and the top-down view (Ctrl+S).
5. Slew to a point on the airport such as a ‘T’ junction of a runway and a taxiway. Put the crosshairs right where the centerline of the runway and taxiway would intersect.
6. On AFCAD, select everything on the window by either pressing Ctrl+A, or by choosing Select All from the Edit menu.
7. Hold the Shift key down to prevent the selected objects from becoming un-selected, and use the mouse to drag the entire airport map.
8. You should see red crosshairs on the AFCAD map corresponding to where your aircraft is positioned in Flight Simulator (e.g. at the runway/taxiway junction). Move the airport so that the runway/taxiway junction lines on the map are under the crosshairs and release the mouse.
9. Slew around to other junction points on the visual airport and check that they register on the AFCAD map. If not then you may have to drag the taxiways and possibly the runways individually to make them line up.  You can select several taxi lines at the same time by holding down the Shift key while clicking on them, or by dragging a rubber band around them.
10. When you have the registration completed, from the AFCAD File menu save the airport and exit.
11. You can now run Flight Simulator and test the registration.

Overlay refers to the practice of layering one or more copies of the same airport on top of a base airport, containing different features, such as parking and open runways, in order to open more active runways than the stock FS ATC would normally permit.  This was a common practice with FS2002.  AFCAD 2 cannot currently produce overlays for FS2004 airports, as that requires the ability to output a file for a new airport and that function is not in this version of AFCAD.  It is still unknown as to whether overlays will be possible or practical to implement in FS2004 given the new scenery format and ATC operation.

This version of AFCAD 2 cannot be used to create a new airport, only to modify existing airports.  That function will be available in a future release.

Before you declare an airport you have worked on to be ‘finished’, you should run the Fault Finder. Fault Finder is a diagnostic tool that will check for some of the most common and problematic faults in airport design. It can be run by choosing Fault Finder from the View menu.

When it identifies a potential fault it will do the following: shift the window to put the fault location at the center of the window, select (turn orange) the problem components, place a red arrow pointing to the fault, and describe the problem.

Fault Finder will identify the following potential faults:

	Non-connecting taxi links: Nodes that come close to, but don’t really connect to links. AI will not cross these ‘dead-end’ links. This can result in AI not being able to leave or enter entire sections of the airport. If a parking spot is unconnected it can result in a large number of other parking spots being unavailable.
	Overlapping non-connected nodes: Similar to the above, AI will not cross these unconnected nodes.
	Hold-short nodes too far from the runway: The red circle indicates the maximum distance a hold short node can be from the edge of a runway (225 feet). If an AI aircraft tried to enter the runway at this taxiway it would freeze at the hold-short node and eventually disappear. Fault Finder will automatically turn on the red limit circles when it finds such a problem, but you can also turn them on and off manually using the Show Hold Short Limits item under the View menu.

Fault finder will also check for unconnected parking spots, orphan nodes, isolated taxiways segments, overlapping connected nodes, missing Start Locations and incorrectly labelled runway taxiway segments.

Note that Fault Finder locates potential faults, and in some cases you may decide that the identified potential fault is not really a problem and can be left as-is.

While running Fault Finder you can skip over faults and proceed with further tests. You can also leave the Fault Finder window open while you fix a fault. If you find a fault and correct it then Fault Finder will automatically run the same test section over again to verify the fix before proceeding to the next test.

You should also manually check for the following problems, which Fault Finder does not test for :

Runway links are all black: If you have been working on runway taxi links, make sure the runway links are all black. A black line tells the AI not to use a runway for taxiing, except to enter or exit the runway, or if there is no other route. The black taxi line should run the entire length of the runway, including any overrun areas.

Taxiways are all blue: Conversely, make sure all taxiways are blue.

Contiguous Taxiways: Use the taxiway designator cycle commands ‘T’ key and Shift+T to cycle through and highlight all taxiways, or at least the ones you worked on, to make sure the taxiways are all labelled correctly and there are no gaps.  A gap caused by an incorrectly labelled segment can result in misleading ATC taxi instructions.

Note: some of the most common problems with airport designs can be detected by using the Fault Finder tool, run from the Tools menu.

This ReadMe document has no pictures
The pictures are all in separate .gif files, and all those files should be in a separate folder named ‘Pics’. Sometimes that folder does not get created properly.

No new boarding bridges (jetways)
AFCAD doesn't create boarding bridges at a terminal building.  The "gates" referred to in AFCAD documentation are parking spots, usually at or near terminals.

AI get stuck at a hold short point and don't move
This will happen if a hold short node is too far from the edge of the runway. The hold short nodes should be no farther than 225 feet (68.6 m) from the runway edge. If AI get stuck when they line up behind an aircraft at a hold short point, then placing a normal node just behind the hold short node will usually fix this. (see Hold Short Node Limits).

AI get stuck on the runway preparing for takeoff
This can happen if there is no hold short node for the taxiway connection to the runway.

AI don't stop at a hold short point
The hold short node is probably too close to the runway, or is actually on the runway.

I don't see red crosshairs anymore
Make sure FSUIPC is installed by checking for FSUIPC.dll in the FS Modules folder. Also, make sure you are at the same airport in both FS and AFCAD.

ATIS doesn't work
Unlike other tower frequencies which have the airport name in the Name field for the comm frequency, ATIS requires the ICAO identifier for the airport in that field (e.g. KLAX).

The changes I made do not show up in Flight Simulator
After you save changes to an airport using AFCAD, you must restart Flight Simulator to allow it to re-index scenery changes.

Do I still need a loop to allow aircraft to make U turns on a runway?
AI Aircraft in FS2004 now re-center at the end of the runway after they make a U turn so you don't need turn-around loops to force them to re-center.

Aircraft disappear after landing
You must have enough parking spaces of a large enough size for all the aircraft that are landing or they will disappear when they slow down on the runway. If that is not an issue then the problem is probably caused by an unconnected parking spot or an unconnected node/link somewhere. The AI will be assigned the next available parking spot in sequence from the parking list and if the next parking spot is unconnected to the taxi system then the AI software will consider the airport full (for that size of aircraft) even if there are plenty of other connected parking spots available further down the list. Use the Fault Finder tool to locate unconnected links.

Aircraft disappear at parking spot when ready to depart
This it is usually caused by an unconnected taxiway link. Use the Fault Finder tool to locate unconnected links.

I moved or added the tower symbol, but the tower view point didn't change
This can occur if you start at an airport using the default flight, or any saved flight. When you save a flight in FS it saves the tower view point along with all the other flight parameters, so if you change the view point it will be overridden when you recall a saved flight. The settings for a saved flight are contained in text files with the extension ".FLT" in the folder FS9/Flights/other/ . You can easily find the tower location in the .FLT text file and modify it to ensure your saved flight uses the new tower view point. The tower location looks like the following:

[Tower]
Latitude=N049° 04' 27.5052"
Longitude=W123° 00' 57.1697"
Altitude=+000059.00

My airport has no control tower symbol
Many stock airports, even a lot of major airports, don't have a fixed tower view. You can add one or use the default tower view that FS provides when no fixed view is specified.

No progressive taxi lines
If you request progressive taxi instructions and the pink progressive taxi line is not displayed, then you may have the Airport Reference Point at the wrong elevation. You can check the elevation of the visual scenery for your airport using the Shift+Z key display when taxiing or parked at an airport in Flight Simulator. This is the elevation of the aircraft body, so subtract a few feet to get the ground elevation. The Airport Reference Point should be close to this elevation.

AI park in parking spots too small for their size
Parking spots are assigned to aircraft based on the parking spot radius and the size of the aircraft. Older add-on aircraft don't have the aircraft size encoded and may use the wrong sized parking spot. The size (radius) is normally encoded in the aircraft .mdl file, but older (non GMAX built) aircraft use a different type of .mdl file that does not encode the aircraft size. It is not possible to fix this.

AI bunch up in one area when parking at the terminal or ramp
Parking spots are assigned to aircraft in the order they appear in the Parking List window. Use the Randomize button on that window to mix-up that order and spread out the AI.

AI park in the wrong airline's parking spots
When using code-assigned parking. This can occur if there are too many aircraft of a specific airline for the parking spots available for that airline.  Reduce the AI flights for that airline or create a number of uncoded overflow spots at any open areas of the airport to absorb the excess aircraft. 

New runway conflicts with terrain
If you create a new runway for a stock airport then you may find the runway is outside the flat area of the airport and parts of the terrain stick up through the runway, or it is underground or floating in air.  This version of AFCAD can't adjust the airport area polygon (flat area) but future versions may be able to do that.  In the mean time, you can correct this either by putting a Flattening Switch in the scenery.cfg file, or create a small .bgl with a flattening polygon encompassing the new runway.  FSSC or another scenery design tool can be used to produce such a flattening polygon.

A new runway doesn't appear
If the elevation is incorrect then the runway can be drawn below ground level and be hidden.

Spikes and pointy projections at taxiway connections
This is a by-product of the Flight Simulator taxiway drawing function.  You can sometimes get rid of or reduce these projections by changing the link angles or ‘jiggling’ the connections.  Note that AFCAD draws taxiways using similar, but not identical methods to FS, so a projection that occurs in AFCAD might not always appear in FS, and visa-versa. 

Can I use my own textures for runways, taxiways, aprons? 
There does not appear to be a way to do this, although we may have to wait for the scenery SDK to arrive to be sure..

Can I change the curves used for taxiway joins?
No.  This is fixed by the Flight Simulator taxiway drawing functions.

Can I change taxiway and runway marking styles and colours?
No.  This is fixed by the Flight Simulator taxiway drawing functions.

If you have problems or questions about airport design and AI operation, first try to get help on a forum where scenery and airport design experts congregate, such as:

www.ProjectAI.com
www.Avsim.com
www.Simviation.com

If you have problems with AFCAD itself then you can contact me at:

Lee Swordy

Swordy@rogers.com

AFCAD, and this document are copyright © 2003 Lee Swordy. AFCAD and this document may not be distributed for commercial purposes or posted in the public domain without the author’s consent.

Microsoft and Microsoft Flight Simulator are trademarks of Microsoft Corp.