When I was reinstalling A2A aircraft for P3Dv4, I grumbled what the heck the developers are doing in altering the aircraft installation folder from “SimObjects” to “Prepar3D v4 Add-ons” under Documents. But after reviewing the file hierarchy further, I have to admit that it is in fact a nice user-friendly touch.
The move not only avoids the chance of messing up with original files in P3D, but it also can eliminate the need of reinstalling aircraft after P3D is forced to clean install again for whatever reasons or when update is available.
Under the new structure, the P3Dv4-ready A2A installer (in my case) added the aircraft location to the “add-ons.cfg” in the Prepar3D.cfg directory after
installation. Then created an XML file called “add-on.xml“, which contains all the sub-folder information, in the root directory of the aircraft folder as well.
Since these two files are basically the keys “telling” P3Dv4 where to look for 3rd-party aircraft in the system, it is then, in theory, possible by altering these two files, to let P3Dv4 to run with other aircraft already installed in earlier P3D versions, or even in FSX as well.
To verify this presumption, I tried adding the FSX and P3Dv3 locations on my computer to the add-ons.cfg, and duplicated a copy of the add-on.xml in their root directories.
It works…well, in a way.
First, P3Dv4 (same to FSX and earlier P3D) doesn’t accept multiple aircraft with identical names. For example, FSX, P3Dv3 and P3Dv4 all have Mooney_Bravo in their aircraft line-up. Adding the whole aircraft library from FSX and P3Dv3 to P3Dv4 inevitably results in errors.
Second, not all FSX or 3rd-party FSX/P3D aircraft are compatible with P3Dv4 or work properly in P3Dv4 via this approach.
Third, even though the first conflict issue can be easily fixed by renaming the corresponding aircraft folders in FSX and P3Dv3 into something different, say Mooney_Bravo_FSX and Mooney_Bravo_P3Dv3 respectively, the multiple occurrences of the same aircraft in P3Dv4 is still confusing and annoying.
Anyway, regardless of these handicaps, the new aircraft file structure does open up the possibility for P3Dv4 to run with many exisiting 3rd-party aircraft, with or without updated P3Dv4-ready installers.
Moreover, this tweak is particularly valuable to those aircraft whose developers are out of service, such as the Duke B60 and Turbine from RealAir Simulations.
At present, I have created a number of specific folders and copied the aircraft I need from FSX or previous installs onto them accordingly based on the new structure. This in practice eliminates the conflicts and drawbacks resulted from adding the entire FSX and P3Dv3 SimObjects to P3Dv4 as example shown above.
Although migration rate isn’t 100 percent successful due to various compatibility issues I have yet to figure out, I am quite happy with what it brings so far.
A thumbs-up to the P3D developers and thank you.