AFCAD

Version 2.21 - for FS2004
User Manual

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.

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.

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.

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.

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.

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.

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.

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.

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.

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:

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

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

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.

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

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.

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.

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.

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 presented 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 expanses of concrete or other material that aircraft can park on or taxi over.  Apron surfaces are not just used for parking areas, they can be used anywhere at an airport that extra pieces of pavement are needed, such as to widen a taxiway for a waiting area, or turn-around bays on runways, or for enlarging junctions.

Aprons are made of polygons formed from straight line segments.  A polygon must have at least three segments but can have potentially hundreds of segments.  Apron polygons will always be drawn underneath taxiways and runways in Flight Simulator and there is no way to make them appear on top of such objects.  Aprons do not have markings of their own, but taxiway markings will appear on top of aprons.  Aprons can also have edge lights.

A Polygon can be essentially any shape or complexity as long as it has only one enclosed area.

If any of a polygon's segments cross over each other, thus forming two ore more separate enclosed areas, then only one of the enclosed areas will be filled in and the actual shape of the apron surface will be unpredictable.  The Fault Finder tool will identify any polygons with crossing segments. Also, it is not possible to create a polygon with internal 'holes'.

To draw an apron polygon, select the Apron Outline drawing tool from the toolbar. The mouse pointer will change to the apron drawing symbol.

Click on the window where you want to create the initial vertex, this will start the polygon drawing mode and a line will follow your mouse pointer.  It is not necessary to hold the mouse button down while creating a polygon, the program will remain in polygon drawing mode until you terminate the polygon.  Click wherever you want to place additional vertices (corners or changes in line direction). The vertex positions do not have to be initially precise, as they can be moved later on.

To terminate drawing a polygon you can use any of three methods: If you bring the polygon line around and click on the initial vertex, thus closing the polygon, then polygon mode will end and the apron surface will be finished.  You can also double-click on the last vertex, or press the Esc key after creating the last vertex.  Note that with the last two methods you do not have to close the polygon, the program will automatically draw a line from the last vertex created back to the initial vertex to close the polygon.  After a polygon has been terminated you can add, delete, or move vertices if needed.

To select a whole apron polygon, for example to move it as a unit or to delete it, just click on any edge of that polygon (not on a vertex or the body of the polygon).  You can also select a whole apron polygon by dragging a rubber band around it, but the rubber band must enclose the entire polygon in order to select it.

To select an individual vertex just click on it.  As when selecting other objects, you can hold the Shift or Ctrl key down to select several vertices at the same time.  When the green vertex diamonds are visible you can also use a rubber band tool to select several vertices as a group. Vertices cannot be selected with the rubber band tool if the diamonds are not shown.

To add new vertices, select the Apron Vertex tool from the toolbar. The mouse pointer will change to the vertex insertion symbol.  You can then click anywhere on the edge of an existing polygon to insert new vertices.  Note that you can only place vertices on the edge of an existing polygon, vertices cannot exist by themselves in an empty area.  Once a vertex has been inserted you can move it wherever you want using the pointer tool.

Deleting Whole Aprons:

Select the whole apron first, for example by clicking on the edge of the polygon, then press the Delete key.

Deleting Vertices:

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

Moving Whole Aprons:

Grab the polygon edge with the mouse (ensure the normal pointer mode is active) and drag the whole polygon to where you want it.

Moving Vertices:

Grab a vertex with the mouse and drag it to where you want it.  You can select more than one vertex by holding down the Shift or Ctrl key while clicking on them, the vertices can then be moved as a group.  This is useful if you want to move one whole side of a polygon. 

IMPORANT NOTE:

Apron polygons may have associated apron edge lights. These consist of strips of lights that are separate entities from the apron polygon. They do not automatically move when you move, delete, or reshape an apron polygon.  If you change an apron polygon and the apron has edge lights you must enter the 'Show Lights' mode, set from the View menu of by pressing the L key, and change the apron lights separately.

Double click the edge of an apron polygon to bring up the Properties window to examine or modify the following settings:

Apron edge lights are laid-down in strips and unlike the aprons themselves these strips do not have to form enclosed polygons.  The strips behave somewhat like the node and link system for taxiways, in that the strips run between end points and they may be linked together to move as groups.  

Light strips can only be seen in 'Show Lights' mode, which is set from the View menu or by pressing the L key.

Note that light strips are shown on the AFCAD screen as a line with a string of lights on it, but the line itself does not appear in Flight Simulator, only the lights.

Light strips are separate entities from apron polygons, they do not even have to be drawn over an apron.  Light strips do not automatically move when you move, delete, or reshape an apron polygon so if you change an apron polygon then you must enter Show Lights mode and change any associated light strips separately.

Note that not all stock airports have apron edge lights, even some major airports like Chicago O'Hare have none, so do not be surprised if you can't find any apron lights at major airports.

Creating Edge Light Strips:

To draw a light strip, select the Light Strip drawing tool from the toolbar. The mouse pointer will change to the light strip drawing symbol.

Click on the window where you want to begin the light strip and hold the mouse button down while dragging the strip out to its end point.

If you click the beginning or end of a strip close enough to another light strip end then it will snap to that end and will link to it.  Such linking is only for convenience while reshaping sets of lights. Unlike with taxi nodes and links, it is not essential that light strips be linked.

Deleting Light Strips:

Select the light strip by clicking on the strip line or by enclosing it with a rubber band, then press the Delete key. 

Moving Light Strips:

Grab a strip with the mouse (ensure the normal pointer mode is active) and drag it to where you want it.  If you grab an end point instead of the line itself then you can move that end point around and adjust the line length and angle.

Light Spacing:

Stock airports that have apron lights use a default light spacing of 200 feet, which is in line with FAA specifications for taxiway lights.  However, many apron edge light strips are smaller than 200 ft, and the spacing of lights does not automatically carry over to adjacent strips.  The result is that the edge lights in stock scenery can be very sparse and uneven, and may not show up at all on smaller aprons or aprons made up of many small segments.  AFCAD provides a setting on the Apron Edge Lights Properties window to force the spacing of strip lights to be evenly spread out over the length of each strip, and each strip will always end with a light.  This means that lights will appear more uniform, and light strips that follow apron edges will have lights at the apron corners, as in the following pictures showing the stock spacing and the AFCAD 'adjusted' spacing:

Adjusted spacing is enabled by default for all new apron lights you create, but it will not automatically affect existing apron lights.  In order to adjust the spacing for existing apron lights you can use the following steps:

• Enable the 'Show Lights' mode (L key).
• Select all the apron edge lights at the airport.  The easiest way to do this is by selecting all objects at the airport by pressing the Ctrl+A key.
• Hold down the shift key to prevent objects from being un-selected and double-click on one of the edge light strips. An Apron Edge Lights Properties window should open up.
• On the properties window, un-check the checkbox labelled 'Adjust spacing to always end at a light' and press OK to close the window.
• Open the window again by double-clicking on an edge light strip then re-check the 'Adjust spacing to always end at a light' checkbox.
• Click OK to close the window again.
• The light strips should now all have evenly spaced lights and each strip should end in a light.

Note that strips do not automatically begin with lights, unless they connect to other strips that end with lights, so you may want to attach a short light strip to the first in a sequence of strips so the sequence appears to begin with a light.

Light Brightness:

The brightness levels for apron lights at all of the stock airports are somewhat lower than the brightness of the blue edge lights on taxiways.  You can increase the brightness of the edge lights by selecting all the edge lights together (Ctrl+A key) and bringing up the Apron Edge Lights Properties window by holding down the Shift key and double-clicking on a light strip, then change the Brightness setting from 8 to 13.  13 is about the brightness level of stock taxiway lights and is the default setting when creating AFCAD edge lights. Note that there is no way to change the brightness of taxiway lights.

Double click on an apron edge light strip to bring up the Properties window to examine or modify the following settings:

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 for landing.  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 runway(s).  This is also, no doubt, to prevent separation problems with crossing arrival/departure streams.  For takeoff ATC will assign the closest runway to the parking spot.

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 reciprocal 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.

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

You can change the direction of a helipad the same way you do with parking spots. That is done by selecting the helipad 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 Helipad Properties window.

Choose the Helipad item from the Insert Menu. You can then fill in the properties for the new helipad and click on the main window where you want the helipad to go.  NOTE: Creating a helipad does not automatically create a Start Location for the helipad. If you want the helipad to appear in the Start Locations list on the Flight Simulator Go To Airport window then you must also create a Start Location for it by selecting Start Location from the Insert menu..

Select it with the mouse and press the Delete key.

Double click a helipad to bring up the Helipad Properties window to examine or modify the following settings.  

Helipads do not come with edge lights but you can create them easily using the Apron Edge Lights tool.

Helicopters do not inherently work as AI aircraft.

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. If the airport has helipads then they can also appear in this list.  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 or helipad 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.  For helipads, the designator will appear as the helipad number.  These should be numbered sequentially from 1 (Helipad 1, Helipad 2, Helipad 3, etc).

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.

When you open an airport AFCAD will display all stock navaids in the vicinity of that airport and you can modify those navaids or add new ones.

AFCAD can work with all the types of navaids that Flight Simulator recognises, these are:

• ILS (localizer, glide path and  DME)
• Marker Beacons (OM, MM, IM, BC)
• VOR and DME (but not TACAN)
• NDB

When you add or modify a navaid the changes will appear in the Flight Simulator Map View and GPS windows and your aircraft instruments will recognise the changes.   There are, however, certain limitations with regard to navaid changes, as follows:

Creation: AFCAD can create any of the above navaids at any location.

Modification: AFCAD can move or modify any navaids that you create. It can also move or modify all stock navaids except for marker beacons, stock marker beacons cannot be changed in any way.  You cannot change the identifiers for any stock navaids but almost all other parameters can be changed.

Deletion: AFCAD can delete any navaids that you create, but it cannot delete any stock navaids.

When you open an airport AFCAD will search the stock scenery files and collect and display all navaids in the vicinity of that airport (25 miles for VORs and NDBs, less for ILS equipment). If you save that airport to a file AFCAD will not save all those navaids to the file.  Instead, AFCAD only saves new navaids or stock navaids that you have modified. These are referred to as ‘mod’ navaids.  If you start Flight Simulator it will use all the original stock navaids in the area except for those that have mod replacements in your airport file, in that case it will use the mod replacements and ignore the stock navaids. It will also use any new navaids from your file.

When you re-open that airport file with AFCAD it will again collect all navaids in the vicinity of the airport and read in the mod navaids from your file. As with FS, it will show the mod navaids instead of the stock navaids they replace.

When AFCAD collects navaids to display it will not collect mod navaids from any other add-on airport files, only stock files and the airport file you have open.  This means that if the same mod navaid is in two different airport files it will only appear once.  Since most navaids are associated with a single airport or its approaches this shouldn't be an issue, but you should keep it in mind if you are modifying enroute VORs or NDBs that aren't located at any particular airport.

Note that mod navaids replace stock navaids based mainly on the navaid identifier.  This means that you can't change the identifier for a mod navaid or it would not replace the original, but instead it would appear in addition to the original. If you create your own navaids you can give them any identifiers you want. Here is an FAA document describing the rules for assigning airport and navaid identifiers for the U.S. : www1.faa.gov/atpubs/LID/CH1.htm

Displaying Navaids:

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

Navaid Symbols:

Localizer	Glide Path	Marker Beacon
DME	VOR	NDB

You can drag them with the mouse or open the Properties window for the navaid and change the latitude, longitude and heading, if applicable.  Note that marker beacons cannot be moved.

Call up the window to create the appropriate navaid (ILS, Marker Beacon, VOR/DME, NDB) from the Insert Menu. AFCAD will fill in the parameters for that navaid using typical values, and in the case of ILS's and markers it will place the equipment were it would typically be located for the given runway, but you will probably want to customize certain parameters such as navaid class and identifier.  You can use published airport and approach charts to fill in most of the unknowns.  If you are creating an ILS for a new runway you should create the ILS only after you have finalized the runway location, heading, length, displaced thresholds, etc.  This saves you from having to adjust the ILS equipment locations if you adjust the runway configuration.

Deleting a Navaid:

Select it with the mouse and press the Delete key.  This only applies to navaids that you have created, stock navaids cannot be deleted.  If you modified a stock navaid and you delete the mod then it will revert back to the stock navaid.  There is no apparent way to ‘exclude’ stock navaids to remove them, you can only move or modify them.  To remove a navaid from service you could change its frequency to an out-of-band frequency such as 0 MHz, but it will still appear on the map.

Double-click on a navaid to open a Properties window. The parameters are explained in the sections of this document for the appropriate navaid (or press the Help button on the Properties window).

You can call up a list of navaids in the vicinity of the airport under the Lists menu.

Navaids and ATC / AI :

The AI aircraft do not appear to use VOR, NDB, or DME information.  They may use ILS information in a limited fashion for guidance, and ATC seems to use the presence or absence of an ILS to decide on runway assignments under some conditions.

ILS

Localizer

Glide Path

DME

Flight Simulator considers an ILS be a localiser, glide path, and DME (approach DMEs only, not DMEs associated with a VOR).  For this description, an ILS is a landing aid built around any type of localiser, whether it meets the definition of a full ILS or not.

Each ILS must be associated with a specific runway at a specific airport.  This association is may be used by the AI and ATC for runway selection, and possibly other purposes.

In addition to the main ILS, you can also have marker beacons and/or NDBs on the approach.  FS considers these to be separate objects and they are not associated with (linked to) specific runways, or even specific airports in most cases.

ILS Equipment Location:

The picture below shows the typical location for ILS equipment.  Each piece of equipment has its own antenna and equipment shed.  AFCAD does not currently place the visible antennas and sheds, or move the stock ones, but a future version will, so you should keep this in mind when placing these objects, otherwise you could find a glide path antenna and shed in the middle of a taxiway in the future.

The long green arrow is the localizer (LOC) beam. The point is at the actual antenna location of the LOC.  Note that the LOC is located at the opposite end of the runway from the approach so it can provide guidance over the entire length of the runway.  Some approach charts are misleading in that they show the LOC beam emitting from the approach end of the runway, they are drawn that way so as not to obscure the runway symbol.

The LOC is normally located about 1000 ft beyond the far end of the runway, but it can be located closer or farther away to keep it clear of obstacles (e.g. taxiways or other runways).  For example, at KORD there is one LOC about 5000 ft from the end of the runway it services.

AFCAD will place a LOC 1000 ft from the paved end of the runway by default, but it will not check for taxiways or obstructions so you should check the siting of the LOC after creating an ILS and move it if necessary. The actual placement of the LOC can sometimes be found on an airport chart, and it may also appear on an aerial photo.

The LOC is normally precisely aligned with the centerline of the runway, except for the rare case of an offset localiser where it doesn't line up with the runway for various reasons such as terrain avoidance and noise abatement, as in the picture below:

An offset LOC is also referred to as a Localizer Directional Aid (LDA).  An LDA usually can't have a glide path unless the offset angle is very narrow.  An LDA is never used with a Cat II or Cat III ILS.

The short green arrow on the AFCAD display is the glide path (GP).  Not every LOC is paired with a GP (a requirement of a full ILS). The point is at the actual antenna location of the GP.  This is always beside the runway at the touchdown point, 1000 feet from the threshold (+/- 250 ft).  The GP can be on either side of the runway but is usually on the side away from taxiways or other sources of interference.  The recommended distance is 500 ft from the runway centerline (+/- 150 ft).

AFCAD will place a GP 1000 ft from the threshold and 500 ft to the side of the runway by default, but it will not check for taxiways or obstructions so you should check the siting of the GP after creating an ILS and move it if necessary. The actual placement of the GP is rarely published, but it may appear on an aerial photo.

The blue box symbol is the DME.  Not every ILS has a DME.  The DME is usually located at either the LOC or GP sites, but it can also be located at a separate site somewhere in between.

AFCAD will place the DME at the LOC site by default, but you can move it anywhere else.  You can copy-and-paste the lat/long for the GP if you want to move it there.  The location of the DME is usually shown on airport charts but it won't usually be visible in aerial photos.  Note that there may be several DMEs at an airport, there may even be two DMEs at one location to serve different runways.

ILS Properties:

Double click the LOC, GP or DME to bring up the ILS Properties window to examine or modify the following settings:

Marker Beacons

Marker Beacon

Flight Simulator provides outer, middle, inner, and back course markers.  Markers are part of many ILS systems but have become less common as DME equipment has become cheaper.  Canada and other countries have removed all middle markers, and many other marker types as well, in favor of DME fixes or other fix types.

Outer markers may be paired with or replaced by low power NDBs, referred to as Compass Locators in the U.S.  This may also be done with middle and back course markers.

Marker Beacon Locations:

All markers are on an extension of the centerline of the runway.  When you create markers with AFCAD it will place them at the typical locations by default and you can move them later if needed.  Exact marker locations, or distances from the runway, can be determined from approach charts.

Outer Marker (OM): The outer marker (and/or Compass Locator NDB) is normally located at the intercept point for the Glide Path.  This is nominally about 3.9 to 4.4 miles from the runway threshold, where the GP beam is about 1400 ft above the runway elevation.  A distance of 3.5 to 7 miles is allowed to accommodate terrain.

Middle Marker (OM): This is normally located 3500 feet from the threshold of the runway, where the GP beam is at the decision height for a Cat I ILS.

Inner Marker (IM): IMs are only used for Cat II or Cat III ILS. They are normally located 1000 feet from the threshold of the runway, where the GP beam is at the decision height for a Cat II ILS.

Back Course Marker (BC):  BCs (and/or low power NDBs) may be used where a back course approach is approved for a runway. They are the equivalent of an OM on a front course.  The BC is typically located 3.9 to 4.4 miles from the threshold of the back-course approach runway.  If a runway has an ILS at both ends then it won't need BC markers.

Marker Beacon Properties:

Double click a marker to bring up the Marker Beacon Properties window to examine the following settings. Note that for stock markers, unlike all other navaids, you cannot change any of the parameters. You can, however, change parameters for markers that you create.  Also note that all markers use the same frequency, 75MHz, so it is not necessary to set a frequency :

VOR / DME

VOR

DME

VOR+DME

You can have a VOR with or without a co-located DME, and you can also have a stand-alone DME (no VOR).  A DME can also be paired with an NDB, but that would require two separate objects.

Flight Simulator is not equipped to use TACAN, a military navaid similar to a VOR; however, DME is built-in to every TACAN, and civilian aircraft can use that DME.  Anywhere a TACAN appears on a real aviation chart FS has placed a DME instead to designate the civilian-usable portion of the TACAN. Similarly, anywhere a VORTAC (a co-located VOR and TACAN) appears they have placed a VOR and DME.

VOR / DME Properties:

Double click the VOR or DME to bring up the VOR / DME Properties window to examine or modify the following settings:

NDB

NDB

NDBs can be used as enroute navaids or as approach aids for airports.  Low power NDBs used with, or to replace, marker beacons are known as Compass Locators in the U.S.

NDB Properties:

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

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.

In addition to modifying existing stock airports, AFCAD can create a new airport, one that doesn't currently exist in the game.  This can be done at any location.  You can create a visible airport with runways, taxiways, aprons, lights, communications, navaids and ATC. However, since the current version of AFCAD can't create taxiway signs or buildings and other structures, such an airport will be somewhat bare. These features will be available in subsequent releases.

Here are the steps for creating a new airport, note that many of these steps can be done in a different order if desired:

1.  Basic Airport Properties

Select the New Airport item from the File menu. This will open the Airport Properties window on which you must enter the basic airport information. Some of this and other information you will need later on can be found in airport publications and airport descriptions found instrument procedures charts.

The Airport Reference Point is usually located at the geographic center of the airport.  For a single-runway airport this is usually the center point of the runway.   It is used as a navigation reference and for other purposes.  The latitude and longitude for this point does not have to be exact.

The elevation can be determined from airport publications, but it may be better to actually slew to the location in FS to check the elevation of the terrain there, as the elevations for real airports and the FS terrain elevations don't always match, and you could end up with an airport at the bottom of a pit.  Latitude/longitude is displayed in FS when in slew mode or by pressing Shift+Z.

The magnetic variation will be shown on airport publications or you can get it from an aviation chart.

If you are creating an imaginary airport then you can enter any Airport ID code you want, as long as it isn't already used for a FS airport.  You can check that by searching for the code on the Open Airport window.  You can give an airport any name you wish.

When you close this window you will initially have only the Airport Reference Point displayed:

2.  Create Runways

Create the runway(s) next by selecting Insert Runway from the Insert Menu.  At a minimum you will need to enter the latitude, longitude, length, width and heading for the runway.  The lat, long, length and width can usually be found on airport charts, or you can just click on the AFCAD window to designate the center point of the runway.  You can move it later if needed.  The runway will automatically take the elevation of the Airport Reference Point.

You can select from two dozen surface types for runways, but most runways are either concrete or asphalt.

Enter the runway designator for the base end.  The base end is usually the lower-numbered runway end (1 to 17). Note that a runway with a heading of 0 degrees would be runway 36, not runway 0, and in that case the base end would be runway 36.

You can use the tab pages on the runway window to set the runway Markings, Lights, and visual slope indicator lights (VASI), or you can set those parameters later. Lighting and VASI can usually be determined from airport charts, and markings can be assumed from the size and type of runway, or can determined from airport photos.

When you close the runway window you should have something like this:

For the next steps of creating taxiways and aprons, they can usually be placed with more precision, especially for a single-runway airport, if you rotate the display so the runway is exactly horizontal.  That will make it easier to tell when taxiway and apron edges are parallel to the runway (you can also use guidelines for this purpose). You can rotate the display by holding down the Ctrl key and using the mouse wheel.  You can fine-adjust the rotation by holding down the Shift key while using the mouse wheel.  Note that you can also use the mouse wheel with no keys to zoom in and out and you can use the mouse wheel button to grab and move the window.

3.  Create Taxiways

Click on the runway-taxiway tool (black line button) on the toolbar and draw a line from one end of the runway to the other.  After drawing this line you should zoom in to the ends to make sure the line is exactly centered on the runway.  If it is not centered it could result in visible gaps where taxiways meet the runway.  You can adjust it later, but it is probably easier at this stage.

Click on the normal taxiway tool (blue line button) on the toolbar and draw the taxiways.  Make sure the taxiway nodes actually connect together, this may require you to zoom in to ensure that taxiway links actually snap to the nodes or links you intend to connect to, rather than just creating separate nodes that are overlapping but not actually connected.  Once a link has been created you cannot connect it to another link or node just by moving them on top of each other, you must erase the link and draw it again.

You will probably want to create at least the major artery taxiways at this stage. You can create the smaller taxiways and crossover segments later if you want.



If you are trying to match an AFCAD airport to an existing add-on scenery airport then you can slew around the airport with an aircraft in FS.  You can align the aircraft with taxiway junctions and press the period key ( . ) to place nodes at those location on the AFCAD window.  You can connect those nodes to form taxiways later.

At this stage you could save the airport and restart FS to go to that airport if you want to see what you have created so far.  You will probably be placed in the middle of the runway because you haven't created any Start Locations yet, and there may be other problems that will be resolved later.

4.  Create Aprons

You can create aprons by selecting the apron tool (button with grey square and green diamonds) on the toolbar. Create a polygon forming the apron edges by clicking on the window at the locations of the vertices (corners) of the apron, then bring the line back and click on the initial vertex or double-click on the final vertex to close the polygon and actually create the apron.  If a vertex is not in the correct position then you can drag it with the mouse after the apron has been created.  If the vertex diamonds are not displayed then clicking on any vertex (corner) will bring them up.

5.  Create Parking

Parking spots should be created over apron surfaces, as parking spots have no textures (e.g. pavement) of their own.  You can create parking spots by choosing the Parking Tool (green circle button) from the toolbar.  You can also choose the parking type (e.g. GA Medium) from the toolbar at this time, or you can create all the parking spots first and set the types and add any airline codes later.  You can click on the window to place a parking spot, then rotate the parking spot to the correct heading.  If you are trying to place parking spots at precise locations and headings, for example to mate with terminal boarding bridges, then it may be better to slew to the parking locations in FS and press the O key (in FS) to drop parking spots. 



After creating parking spots you can change their properties by selecting them and choosing a new parking type or adding airline codes from the toolbar, or you can double-click to bring up the Parking Properties window to make more detailed changes such as changing the gate numbers or radius.  You can select several parking spots at the same time by holding down the Shift or Ctrl key while clicking on them or circling them with a rubber band, then change the properties for them all at the same time.

You must connect parking spots to the taxiway network.  You can run taxiways over aprons if needed (they will automatically go on top) to form a spine for parking connections. For parking connector branches it is better to use the special apron taxi links (green lines), which will assume the surface texture of the apron but still show yellow markings, and lights if enabled. Select the apron taxi link tool (green line button) on the tool bar.  Pull a taxi link out from each parking spot and connect it to the nearest taxiway.  This can be done using several segments if needed.



When you have created and linked all the parking, go to the Parking List window and make sure the parking spots are in the order you want. You should mix the list up a bit if you want to prevent the AI from bunching up, as AI are assigned parking from the top of the list on down when other factors such as parking codes and radius are equal.  You can use the Randomize button or just drag list items around with the mouse to do this.

6.  Create Hold Short Nodes

Finish the taxiway system, if not already done, and create a hold-short node everywhere a taxiway connects to a runway.  Select the Hold-Short Node tool (red dot button) from the toolbar and click everywhere you want to insert a hold-short node.  Hold short nodes are essential for ATC takeoff clearance and they create the yellow hold-short lines on the taxiways.  They must not be any further than 225 feet from the edge of the runway. You can enable the Show Hold-Short Limits function from the View menu or by pressing H if you want to verify that the hold short nodes are within the legal distance of the edge of the runway. 

7.  Assign Taxiway Designators

Set the designators for the taxiways (taxiway A, B, C etc.).  To set a taxiway's designator, select all the segments belonging to that taxiway by holding down the Shift or Ctrl key while clicking on the taxiway lines, or using the rubber band tool, then type the letter for the taxiway into the designator box on the toolbar.  For example, for taxiway 'A' enter the letter 'A' in the designator box and press the Enter key.  The path for taxiway A will appear in Red.  Then select all segments for taxiway 'B' and enter 'B' in the designator box, and so on. You can add segments to an existing taxiway by selecting the segment and choosing the designator from the designator list.



When completed, choose the blank entry in the taxiway designator list so no taxiways remain shown in red.

8.  Set Taxiway Markings

Zoom in and check the taxiway markings.  Most taxiways will have solid edge lines and a center line. Where taxiways run over aprons the taxiways typically have dashed edge lines, indicating aircraft can enter and leave the taxiway as needed in that area.  If you have any taxiway sections that should have dashed edge lines then you can select all the segments in that taxiway section by holding down the Shift or Ctrl key while clicking on them, then double-click on one segment (while still holding the Shift or Ctrl key) to bring up the Taxi Link Properties window.  You can then change the edge line type from solid to dashed on that window.  If you need to change just one side of the taxiway to dashed then it gets a little trickier.  The sides are labelled 'left' and 'right', which is with respect to the direction they were originally drawn.  That direction may not be obvious though, so it may be easiest just to just change one side (e.g. left side) and for any segments that end up with the dashed line on the wrong side, just select them and change the other side to dashed.

9.  Set Runway Lights

Toggle to 'Show Lights' mode by pressing the L key.  Make sure the runway(s) have the appropriate edge lights, centerline lights, end lights and approach lights.  Not all runways will have the full complement of lights, and some smaller airfields may have none.  You can change the runway lights from the Lights tab page on the Runway Properties window. Double-click on the runway to bring up that window and make any changes required.

10.  Set VASI

Most airports with runway lights have some kind of visual approach slope lights such as VASI or PAPI.  These usually go on the left side of the runway, except for larger systems like VASI 16 that go on both sides.  You can enable VASI and similar systems from the VASI tab page on the Runway Properties window. You can often get the slope indicator lights system type for a runway from the airport publications.  When you enable VASI-type lights for the first time AFCAD will insert default values in the fields that will place the lights 750 feet from the threshold of the runway, 20 ft off from the edge, and with a 3.0 degree glide slope.  You can change these values if needed.  Verify the location of the VASI lights on the AFCAD screen to make sure they do not interfere with other airport features, such as PAPI light arrays crossing a taxiway.  Move them if needed to prevent this.

11.  Set Taxiway Lights

If your airport is large enough to have taxiway lights then you can enable them using the Taxi Link Properties window.  You can bring up this window individually for each taxiway segment, but it is much easier to select all the taxiways and change them all at once.  The simplest way to do this is to select all objects at the airport by pressing Ctrl+A, then hold down the Shift or Ctrl key to prevent the objects from being de-selected while double-clicking on any one of the taxi links (the blue lines in the middle of the taxiways).  This will bring up the Taxi Link Properties window.  Set the lights that you want enabled on that window and close it.  Note that centerline taxiway lights are seldom used anywhere but the largest airports. 

12.  Create Apron Lights

Apron surfaces often have sets of blue lights around their perimeters, but these must be created separately from the apron polygons.  Choose the Apron Light Strip Tool from the toolbar. At one of the vertexes (corners) of an apron polygon, press the mouse button and drag a light strip line out to the next corner. Repeat this going from corner to corner until the perimeter of the apron is enclosed in light strips.  You can move a light strip by grabbing the blue line or one of the end crosses with the pointer tool.



Once the lights are complete you can toggle out of Show Lights mode (L key).

13.  Create Start Locations

You should have start locations for both ends of every runway. Note that start locations in FS stock airports are located at the end of each runway, but they can actually be located anywhere you want.  Use the Start Location item under the Insert menu to insert a start location. Click on the AFCAD screen where you want to place the start location. If you click on a runway itself AFCAD will automatically use the runway heading and designator for the start location.

14.  Create Tower Viewpoint

You don’t have to have a tower viewpoint, even a lot of major stock airports in FS don’t have them. FS will use a default tower view somewhere near where your aircraft is if you don’t assign one. You can assign one by choosing Tower Viewpoint from the Insert menu. Keep in mind that this has nothing to do with AI or ATC and it won't insert an actual control tower at that location.

15.  Create Comm Frequencies

Open the Comm Frequencies item under the List menu to create all the radio channels you need for ATC. Click the Insert button on that window to create them. Many comm types, such as FSS, aren’t used for anything in Flight Simulator but they show up in the airport information window.  If you want an ATC controlled airport then you will need to insert at least a Tower frequency and possibly a ground frequency and ATIS.  ATIS must use the Airport ID code for the name.

16.  Create ILS

If you intend for your airport to have ILS then you will need at least a localizer (LOC) and either a DME or Marker Beacons or approach NDBs, or all of the above. For precision approaches you will also need a glide path (GP).   Click the ILS item under the Insert menu and select the runway you want to have an ILS.  The ILS properties window will open with GP and DME already enabled and the all the LOC, GP, and DME locations and parameters all pre-filled with typical settings.  If you are recreating an existing airport you could change some of these to the 'real' values, such as setting the ILS Ident and Frequency and disabling the GP or DME if those are not used.   If you are creating your own airport then you may only need to set the ILS Ident. Refer to the ILS Ident description for Identifier conventions.

When you close the ILS Properties window then Show Navaids view mode will be enabled (N key) and you will see the new ILS.  If the LOC or GP positions (points of the arrows) end up on a paved area then you should move them onto an open area.  Keep the LOC aligned with the runway centerline and the GP point 1000 feet from the threshold, but you can move the GP to either side of the runway.

If you want to have marker beacons (not every country uses them) then click the Marker Beacon item under the Insert menu and select the runway to get the beacons.  You will probably want an OM and a MM.  If you are creating a Cat II or Cat III ILS (not typical of most airports) you will also need an IM, otherwise don't enable it.  If your runway will only have ILS at one end then you can also create a Back Course marker.  You can use the default marker distances, unless you know the actual locations.  When you close the window the markers will be created.

17.  Create NDBs

If your airport is of any size it will probably need at least one NDB.  You can have a high power NDB as the airport's terminal beacon, unless you have a nearby VOR, and low power NDBs for the front course approach and back course approach (if used).  The approach NDBs would typically be at the outer marker and back course marker locations. Click the NDB item under the Insert menu and you will be presented with the NDB Properties window.  You can click on the screen to set the position for the NDB, or type in the lat/long if you have that information from an approach chart or other published source.  If you are creating your own airport then refer to the NDB Ident section for the identifier conventions.   If the NDB is to be the terminal beacon for your airport then set the Class to H (high power).  An approach NDB will have the class set to MH, or possibly Compass Locator (low power).

When the airport layout is completed, always run the Fault Finder tool, from the Tools menu.  That tool looks for many common problems in airport design, such as unconnected taxi links.

19.  Flattening and Exclusions

You can save your airport and try it out in Flight Simulator at this stage.  You will likely find the airport has trees and shrubs and possibly buildings located on the runways, aprons and taxiways.  This is Autogen scenery created by Flight Simulator.  You can inhibit Autogen scenery at your airport by either creating an exclude switch in the scenery.cfg file, or by creating an exclude polygon file using a scenery tool such as FSSC (a future version of AFCAD will do this for you).  An exclude switch in the scenery.cfg file is the simplest method, but you are limited to a single rectangular exclude switch per scenery area.  If you plan to create only one new airport then you can just insert the exclude switch in the Addon Scenery area, otherwise you can create a new scenery area (folder and block of parameters in the scenery.cfg file) for each airport and put an exclude switch in each one.

You may also find the airport surface is not very even.  FS will level off runway, taxiway and aprons surfaces for you, but you may find that these surfaces cross over dips and valleys in the terrain where they appear to float.  You may also find there are hills located uncomfortably close to the runways.  These problems can be fixed by either creating a flattening switch in the scenery.cfg file, or creating a flattening polygon file using a scenery tool such as FSSC.  Flattening switches are similar to exclude switches, but you are allowed ten of them in a scenery area instead of just one, and they do not have to be perfect rectangles.

You can determine the latitude and longitude for exclude and flatten switches using the location field in the status bar.  This will show the aircraft lat/long if you have FS running, or the pointer lat/long otherwise.

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.

Apron lights are aligned with apron edges: If you moved, reshaped or deleted any apron surfaces you must switch to Show Lights mode (L key) and check if the apron had any associated edge lights. If so then make sure the edge lights still conform to the shape of the apron polygon.  Apron edge lights are separate objects from apron polygons and do not automatically move with the polygons.

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. If that doesn 't work then make sure your Addon Scenery folder is enabled. This can be verified by checking for the line "Active=TRUE" for the Addon Scenery area in the scenery.cfg file or ensuring that the Addon Scenery area is enabled on the Scenery Library window of Flight Simulator.

I removed an airport (file) and that airport still appears in the FS Go To Airport window.
In Flight Simulator, go to the Scenery Library window (under Settings) and press the OK button to close that window.  The airport should then no longer appear in the airports list. 

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

A helipad doesn't appear in the GoTo Airport start list
If you create a helipad you must also create a start location for it before that helipad will appear in the Flight Simulator Go To list.

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.

Mouse wheel-button doesn't work for dragging or changes windows instead
Recent MS Intellimouse mouse drivers, and possibly others, pre-program the mouse wheel-button for other actions such as window swapping.  If this occurs you can use the Windows mouse control panel to set the wheel mouse action back to Autoscroll.

I can't delete a navaid (ILS, VOR, NDB, Marker beacon)
FS2004 does not allow a stock navaid (one that came with the game) to be deleted or excluded.  You can modify a stock navaid, but if you delete the modified navaid then it will revert back to the unmodified stock navaid.  If you really need to get rid of one then you could change the frequency to an out-of-band frequency, such as 0 MHz.  This will prevent your instruments from seeing it.  It will still appear on the GPS and Map Views though, so you could move it away from the airport and put it in an isolated airport.  This does not apply to marker beacons, which can't be modified at all.

I can't change or move a Marker Beacon (OM, MM, IM, BC)
Unlike other navaids, FS2004 does not allow a stock marker beacon to be changed or moved.  You can create another marker at the same or different location, but the original stock marker will still remain.

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.