Wow, Pride and Prejudice in this forum!

But Cees, on your side it's more Vanity Fair. No, I won't try to help you anymore as long as you keep swamping us with all these irrelevant things and that name dropping. This is a discussion forum and not an arena for show-offs. You don't need help in what you're doing but you would need help in understanding others and explaining. Since you're putting down each and any advice it might help you not to take others for a fool. Your last post is a good start!

And Andy, among us engineers, maybe you unintentionally fueled Cees' "reactions" by introducing lenses and surveyors what worked like Cees' "analogies" in this context. Seems to me there was simply a misunderstanding of the term distortion when Cees took it as lens distortion and you meant perspective. As far as I can see he did nothing else but reconstruct the perspective making use of the clues in the picture, especially the symmetry of crate and airplane.

Take your own example of the tapered wing seen from a wingtip: Measure the root chord and both tip chord lengths, calculate the mean tip chord and the tip/root ratio. If you now know the root to be 12" you also know the tip chord length. Dihedral would make it a bit more complicated but not impossible. That's what Cees did, and in the first place he checked that Ed used a flawless lens and a small aperture. Later, when checking his measurements, he replaced the sagging string by a straight laser beam (quite an effort for a Dutch cheapskate).

I would have asked him for an error estimation, but I didn't dare to in fear of new complications. Anyway, I didn't see any error in his procedure, the more since it's a standard method of surveying or photogrammetry, your two-picture method being another one. They are just very tedious without any utilities. I wish I had a good photogrammetry software (or 3ds Max which is said to have something like the first method), would be much easier also to reconstruct the Simla geometry, but they are expensive.

And Cees, I still wish I had the full-resolution crate picture!