Steam 2026 ADF release with 1998 Mission Editors
Posted: 2026-May-02, 14:18
This thread is subject to change....
Mission editing like it’s 1998
We take a look at a few of the original 3rd party mission editors.
-------------------
First we define a way of arranging the mission files to be compatible with the 2026 version of the game, then we’ll see what needs to be done to hammer the output of the old mission editors to fit.
Note that these editors are the property of their original authors and we will not go into detail of what each editor does.
For simplicity, we’ll call our example mission mod ‘testmiss’ and each set of mission files will consist of the following:
testmiss.pdl
testmiss.mdl
testmiss.udl
testmiss.txt (this will be the Briefing, and it’s optional)
Then the game needs to be aware of the missions, and the recommended way is to copy the existing ‘td_miss.txt’ and ‘td_tours.txt’ from the game’s f22data directory and edit in the new mission file names.
Any game mods including missions must be placed in the ‘MODS’ directory located wherever Steam has installed the game.
So, the steps to add our mission would go like this:
1. Locate the ‘MODS’ directory and create a directory called ‘testmiss’ inside it.
2. In the new ‘testmiss’ directory, create another called ‘f22data’
3. Locate the main ‘f22data’ directory from a couple of levels up and copy the files ‘td_miss.txt’ and ‘td_tours.txt’ to the newly created ‘f22data’ directory.
4. Create directories called ‘pdl’,’mdl’,’udl’ and ‘briefing’ so the hierarchy looks like this: Now we need some actual mission files, so we’ll start with ‘Air Combat Designer’ (ACD) which can be found here:
download/file.php?id=2442
On extracting the zip file, we get 3 files. The ‘readme.txt’ instructions should be ignored, and running ‘ADF_ACD.exe’ gets us this: On my PC, I got a lot of popups as can be seen on the left of the picture, but they can be closed without issue.
Without changing and parameters, if the ‘Generate Scenario’, followed by the ‘Save Scenario’ buttons are pressed, we see that the mission files are now generated: The ‘SIMULTOR.TXT’ file can be ignored, but ‘adf_dmd.mdl’,’adf_dmd.udl’ and ‘adf_dmd.pdl’ should be copied to the appropriate directories created earlier. ACD can now be closed.
It seems ACD does not produce a Briefing file, so our ‘testmiss’ directory now looks like this: Now we need to edit some files with our favourite text editor.
First, open ‘adf_dmd.pdl’ and change lines 5 & 6 from:
MDL_FILE ..\ADD_ONS\ADF_DMD.MDL
UDL_FILE ..\ADD_ONS\ADF_DMD.UDL
to:
MDL_FILE ADF_DMD.MDL
UDL_FILE ADF_DMD.UDL
Now, open ‘td_tours.txt’ and edit it so it looks like this: We are basically adding an extra tour, so the number of tours on Line 12 needs incrementing, then we add some details of the tour name etc.
Doing it this way means that all the existing missions are still available.
Next, edit ‘td_miss.txt’ in a similar fashion.
Line 10 needs to change from:
NUMBER_OF_MISSION_TYPES 7
to:
NUMBER_OF_MISSION_TYPES 8
then the end of the file should look like this: Note, the “none” on the last line is where the Briefing filename would go if there was one.
Now it’s just a case of priming Steam to use the mission.
Right click the game in your Steam library, then select ‘Properties’
Add in the Launch Options which mod to use: Start the game, and the extra tour should be visible
Mission editing like it’s 1998
We take a look at a few of the original 3rd party mission editors.
-------------------
First we define a way of arranging the mission files to be compatible with the 2026 version of the game, then we’ll see what needs to be done to hammer the output of the old mission editors to fit.
Note that these editors are the property of their original authors and we will not go into detail of what each editor does.
For simplicity, we’ll call our example mission mod ‘testmiss’ and each set of mission files will consist of the following:
testmiss.pdl
testmiss.mdl
testmiss.udl
testmiss.txt (this will be the Briefing, and it’s optional)
Then the game needs to be aware of the missions, and the recommended way is to copy the existing ‘td_miss.txt’ and ‘td_tours.txt’ from the game’s f22data directory and edit in the new mission file names.
Any game mods including missions must be placed in the ‘MODS’ directory located wherever Steam has installed the game.
So, the steps to add our mission would go like this:
1. Locate the ‘MODS’ directory and create a directory called ‘testmiss’ inside it.
2. In the new ‘testmiss’ directory, create another called ‘f22data’
3. Locate the main ‘f22data’ directory from a couple of levels up and copy the files ‘td_miss.txt’ and ‘td_tours.txt’ to the newly created ‘f22data’ directory.
4. Create directories called ‘pdl’,’mdl’,’udl’ and ‘briefing’ so the hierarchy looks like this: Now we need some actual mission files, so we’ll start with ‘Air Combat Designer’ (ACD) which can be found here:
download/file.php?id=2442
On extracting the zip file, we get 3 files. The ‘readme.txt’ instructions should be ignored, and running ‘ADF_ACD.exe’ gets us this: On my PC, I got a lot of popups as can be seen on the left of the picture, but they can be closed without issue.
Without changing and parameters, if the ‘Generate Scenario’, followed by the ‘Save Scenario’ buttons are pressed, we see that the mission files are now generated: The ‘SIMULTOR.TXT’ file can be ignored, but ‘adf_dmd.mdl’,’adf_dmd.udl’ and ‘adf_dmd.pdl’ should be copied to the appropriate directories created earlier. ACD can now be closed.
It seems ACD does not produce a Briefing file, so our ‘testmiss’ directory now looks like this: Now we need to edit some files with our favourite text editor.
First, open ‘adf_dmd.pdl’ and change lines 5 & 6 from:
MDL_FILE ..\ADD_ONS\ADF_DMD.MDL
UDL_FILE ..\ADD_ONS\ADF_DMD.UDL
to:
MDL_FILE ADF_DMD.MDL
UDL_FILE ADF_DMD.UDL
Now, open ‘td_tours.txt’ and edit it so it looks like this: We are basically adding an extra tour, so the number of tours on Line 12 needs incrementing, then we add some details of the tour name etc.
Doing it this way means that all the existing missions are still available.
Next, edit ‘td_miss.txt’ in a similar fashion.
Line 10 needs to change from:
NUMBER_OF_MISSION_TYPES 7
to:
NUMBER_OF_MISSION_TYPES 8
then the end of the file should look like this: Note, the “none” on the last line is where the Briefing filename would go if there was one.
Now it’s just a case of priming Steam to use the mission.
Right click the game in your Steam library, then select ‘Properties’
Add in the Launch Options which mod to use: Start the game, and the extra tour should be visible