Here is a truly new model, one that has never existed in paper so far as I know. A customer called up wanting one for her 92 year old father, who flew them in the late 30s. I said, no problem, I'll just make a few tweaks to the FG T-6 & voila - a BT-9.
While the T-6 is a much improved later derivative of the BT-9, they really aren't the same aircraft except in superficial outline, and to heap complication atop complication, the FG T-6 is not, pardon my honesty, a model with either good fit or proper proportions. So the "quick tweaks" turned into a major overhaul of the entire model. Well, at least now we've got a new addition for the FG stable (once Chip gives it the OK).
So what differentiates a BT-9 from a T-6? Lots. The engine, for one thing, is considerably smaller on the BT-9, a 475 HP Wright instead of that massive 600HP Pratt Whitney. The landing gear is fixed, with a nice set of fairings and spats. The wingtips are round, not square. The rudder is round, not tapered. The fuselage is fabric covered, not monocoque.
Making all those changes to the T-6 was work enough, but other fixes were needed: the wing/fuselage juncture is a disaster (as seen in this first of several trial builds) ---
The windscreen and canopy were way too large and had to be shrunk, then reshaped. And I can't abide the design technique of making the vertical fin integral with the fuselage; there's just no way to properly achieve all the myriad curvatures back there doing that. The first thing I did was completely redesign the empennage, built with cambered surfaces and wrapped leading edges, so it'd look much closer to what a real airplane looks like ---
Fixing that wing/fuselage juncture was a real bear, but descriptive geometry saves the day in this business, and I made a juncture and fairing that not only looks like the real airplane, but is EASY to assemble as well (now THAT'S an achievement). Here's the real airplane ---
And here's my juncture and fairing ---
I thought the landing gear might be difficult, but it turned out to be ridiculously easy, just a folded over fairing and the wheel glued to the inside surface. Simple, yet strong. The landing light in the photo, incidentally, is a photograph of a Beech Bonanza's landing light photoshopped into the leading edge. Note also that the leading edge of the wing is round, not creased, and NO fold line - that 304 insignia wouldn't look good across a folded leading edge ---
Somehow I got it all done and looking halfway decent; here're the rest of the pictures:
It took three trial builds to get there, (and innumerable reworks in photshop), but definitely a worthwhile adventure