Sorry for the late reply SabreHog.
Is there a reason "cn" has been replaced with "MSN"? I realize it's a "minor" quibble, but "construction number" has been a term of art in the aviation enthusiast community for quite a while (published authors like Yefim Gordon et al even make use of it, for that matter), so I don't see why the change was warranted-we all know what it means, and it's not like it wasn't intuitive for non-aviation people to figure out.
I'm not sure why all of the above was done. The developers worked together with the editors on that. On the upload page it's listed as msn/cn.
Also, why the decision to split off line numbers from c/ns? The best thing about having them together was that it made for a genuinely unique entry, so that you would only see examples of the particular aircraft you were looking for. Plus, searching for a line number doesn't really make sense, as it's going to bring up several totally different aircraft from both Boeing and Douglas, and, on the same point, appears to only apply to aircraft for those two manufacturers, which seems an equally odd choice.
You are correct that only Boeing and Douglas use line numbers. I agree with you that it was nice to have the unique combo of msn/ln, but you can still search for this and come up with the correct results. This goes for the search page as well as the cross data search for a photo.
What about McDD aircraft with two c/ns, like the F-15s? Or aircraft with several combined c/ns, like many of the Eurofighters or Tornados, or aircraft from Aermacchi? Or Soviet aircraft with attached "fuselage numbers", which, while similar, do not really fit the same mold? Combining all this data in one field makes a lot more sense than dividing it up, particularly dividing it up unequally like this.
I've asked the editors about this and will report back when I have an answer.
Additionally, the search function doesn't seem to work properly at all. I tried searching for "PA-28R-201" recently, and it only produced about 20 results, including several other Piper Arrow variants, which is not what I was looking for, much less representative of what I know for a fact to be the numbers of PA-28R-201 Arrow III photos in this database. Worse, I tried searching "Aeropro Eurofox" and it didn't produce any results at all; I ended up having to site search on Google just to find that the database contains many entries for that aircraft type..
I find well over 100 results when I search for "PA-28R-201". For the Aeropro Eurofox, I find 92 results. (Search --> Advanced search --> Basic type: Aeropro Aerofox --> Generic type: Aeropro Aerofox --> Version: Aeropro Aerofox --> "Show me the photos"). Since my results are very different to yours, I'm wondering if you used the advanced search function to search?
Finally, what exactly is a "basic type" supposed to be, and how does it differ in any substantive way from generic variant? And why are all three of these displayed in the photo information? Far from helping, it would only serve to confuse the uninitiated, and it looks extremely messy and poorly arranged displayed that way.
They don't seem to be different. We do plan to clean up the photo information to a minimum, which should take care of this point. However I don't know when this will happen.