Here is the actual file list sorted by type that are in the FS4 Aircraft SDK DR400 folder which you run the FS2toFS4 converter tool on.
You just do not get these files in your standard end user Aircraft install folder.
Here is the Do27 installed aircraft files listing.
So no, you cannot run the FS4 aircraft converter on the Do27 folder.
Well, if you know something don't keep it to yourself as inquiring minds want to know how to convert and FS2 airplane without have the actual 3D CAD program source files.
Ok, are you sure? Well, guys like you should know that there is also an email address at IPACS. 
I am sure and certain that you will get a clear and fast answer for your conversion. 
Ok, are you sure? Well, guys like you should know that there is also an email address at IPACS
Sorry, I just thought you were just saying you knew how to make FS2 aircraft like the Do27 work in FS4 without requiring the original source files so I wanted to find out how that is possible since I had already read the Aerofly link on what needed to be done to do so and it did not seem possible using the already compiled end user installation files.
Unfortunately here, there are only a small handful of people who know how to work in depth with such files.
Msfs are losing customers hand over fist because slow load times /crashing ect i for one have left, if FS4 did more in the way of microlight they would gain much more, microlight industry in the UK is very bigbigger that people think, popular types skyranger, c42, savannah,foxbat,jabiru,rans to mention just a few.
HEAR HEAR , I would welcome some ultralight aircraft some that I have flown.
Msfs are losing customers hand over fist because slow load times /crashing ect i for one have left, if FS4 did more in the way of microlight they would gain much more, microlight industry in the UK is very bigbigger that people think, popular types skyranger, c42, savannah,foxbat,jabiru,rans to mention just a few.
This is a very good idea, in this case try to ask Just Flight, if their authors would be ready to come back from MSFS, and develop new models for AFS4? And at the same time to make an update concerning the AFS2 models, so that they are compatible for AFS4. Not sure? but as they say, hope keeps you alive
Looks nice shame we cannot modifi a few from MSFS, and why arnt orbix or any other third party devolopers doing FS4, seem like it's dying before it's begun.
Such a shame as it could be the best flight sim ever, let's face it (VR hands) are brill, no one has even got anywhere near yet.
Can anyone build aircraft or aifields, a shed loads of airfields in the uK but not on the sim,
Looks nice shame we cannot modifi a few from MSFS, and why arnt orbix or any other third party devolopers doing FS4, seem like it's dying before it's begun.
In any case, ORBX has become a real gas factory, moreover it develops very little new for MSFS, but more as a subcontractor. More than 70% of products at ORBX come from third-party developers. So these are the ones that we would need to recover for FS4.
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Can anyone build aircraft or aifields, a shed loads of airfields in the uK but not on the sim,
There are already a few small airfields for UL in Denmark and North-West Germany, which usually fit the images well. I have already finished some for Wales and will upload them to Flight-Sim.org soon.
