For years I tried to find the 12 Squared Gnat 750, to add to my slowly growing collection of 1/72 UAV models. In many years of weekly Ebay checks I never saw one, although one was offered and sold so I learned afterwards. I finally obtained one through Tom 'MAI/ESM' Young. Many thanks again Tom!
Alain 'Colossusfr' built the 12 Squared model and shows it on the BritModeller and Maquette 72 (French) / (translation) forums.
The 12 Squared instructions show a great drawing, but it fuelled the question whether photos of the real thing showed the short or long version, or possibly both? That question bothered me for a long time, until I found the time to translate the drawing into a simple wire model, that could be laid over a photo using six degrees of freedom plus perspective. A custom-made piece of software made it possible, thanks again Tjarko!
Here's the first photo I tried. I think the results are convincing: the small version can't be made to fit, whereas the long version fits nearly perfectly. The main landing gear is splayed out in the photo, but the nose leg is definitely modeled too long and too far forward.
The second photo showed the same result. It was also clear that this one used the 60" prop.
Over to the Gnat that I want to portray: a special development for the CIA allowing satellite communication. It had a huge satcom radome fitted on the top, and I wanted to establish its measurements. With trail and error I defined the axis of the radome, plus various diameters and the leading and trailing edges of the pylon. Then I overlayed the wire model on the second photo, showing that a bit of tuning is still required.