HLAXP is a plugin for X-Plane flight simulator to provide the ability to participate in HLA federation executions. HLA (High Level Architecture) is a standard for distributed simulations. HLA was developed by the US Department of Defense and has been approved as an open standard through the IEEE (IEEE standard 1516). HLAXP is currently using the former HLA 1.3 draft standard.

HLAXP has been tested with X-Plane 7.30 on Windows XP using the following RTI's:

MäK RTI 2.1

Only a Windows version of HLAXP is available because there is no RTI that supports Macintosh (april 2004)

HLAXP is currently only available as an evaluation version (HLAXP v0.95). This beta version of HLAXP will automatically resign from the federation three minutes after joining. See Customer Specific Development below for professional usage

Windows version: HLAXPv0.95.zip

  1. Download the HLAXP distribution file and unzip it in a temporary folder
  2. Copy the file hlaxp.xpl to the plugins folder in X-Plane
  3. Copy the files hlaxp.ini and hlaxpexp.ini to the X-Plane preferences folder
  4. Check the hlaxp.ini file to set your desired federate name, federation name and path to your fed-file (as fed-file you can use the bundled hlaxp.fed)
  5. Done!
Before using HLAXP you need an RTI installed, see your RTI documentation for specifics.

HLAXP adds a menu to X-Plane, three menu items exist in v0.95:
  1. HLAXP tries to join the federation (and maybe to create it if specified in the file hlaxp.ini) (this may freeze X-Plane a couple of seconds depending on your RTI)
  2. HLAXP creates the user aircraft in the federation
  1. HLAXP removes the user aircraft from the federation
  2. HLAXP tries to resign from the federation (and maybe destroy it)
Create Ownship
  1. HLAXP creates the users aircraft in the federation (the aircraft is removed when the user has crashed)
HLAXP receives the interaction StartResume and sets the date and time according to the parameters. When a MunitionDetonation interaction is received, the DetonationLocation and/or TargetObjectIdentifier+RelativeDetonationLocation is used to calculate if the users aircraft was hit. The following DetonationResultCodes is considered as a hit when close enough (currently 100m):

General configuration

HLAXP is configured using the file hlaxp.ini, the syntax is simple and straight-forward:
<Parameter name> <value>
See the following table for configurable parameters:
Parameter Name Value
CREATE 1 = YES, 0 = NO
FEDERATION Name of the federation execution to (create and) join
FEDERATE Name of the X-Plane federate
FEDFILE Path to the fed-file (only necessary when creating the federation)
TIMESTEP Number of seconds between updates (valid range: ]0.0 , 2.0])
SITEID SiteID used in FederateIdentifier
APPLICATIONID ApplicationID used in FederateIdentifier
FORCEID ForceIdentifierEnum8 value according to SOM (valid range: [0 , 3])

Entity type configuration

To specify the entity type for exported aircrafts, use the file hlaxpexp.ini, the syntax is simple and straight-forward:
<Keyword> <Kind> <Domain> <Country> <Category> <Subcategory> <Specific> <Extra>
Keyword is a string used as a keyword to identify a specific aircraft in your X-Plane installation, the keyword is matched with the path or filename of your aircraft file (first match used). The rest are integers matching the DIS-enumerations.


Matching an X-Plane aircraft with the string "B-747" in the pathname or filename with a US "Boeing 747-400" (according to DIS Enumerations document 2003):

B-747 1 2 225 57 1 1 0
The "Extra" is not specified in the document, can eg. be used to identify a specific airline or even a specific aircraft.
HLAXP uses a Simulation Object Model that's a part of the RPR-FOM V2.0 Draft 9 (see SISO for more information on RPR-FOM).

HLAXP v0.95 only publishes one type of object - Aircraft, with the following attributes provided:
EntityType Fully user configurable using HLAXP configuration files
EntityIdentifier SiteID and ApplicationID user configurable
Spatial Position, Velocity, Acceleration and Attitude using SpatialFWStruct, no dead reckoning implemented
ForceIdentifier Fully user configurable using HLAXP configuration file
HLAXP v0.95 subscribes to the interactions StartResume and MunitionDetonation. The StartResume interaction is only used to set the date and time (no start/stop/pause functionality).
HLAXP v0.95 SOM vs. RPR-FOM2 D9
Information links
X-Plane SDK
Defense Modeling and Simulation Office HLA
Customer Specific Development
Memention are willing to adapt HLAXP to your specific needs, e.g modify the SOM or develop specific HLA functionality to make X-Plane to fit into your federation. Please contact us if you have any questions so we can discuss the details.

We can also make the source code available for customer specific needs. Please contact us if you have any questions so we can discuss the details.

Copyright © 2009 Memention AB