Although the Gotha Go 242 glider and its motorized variant, the Go 242, are fairly well-known by German aviation enthusiasts, the P.35 and P.39 projects that derived from them are more obscure.
The two projects were both conceived as transport aircraft with increased bay area and good loading capacity, to be built with mixed material so as to reduce costs, and powered by Bramo 323 engines.
The twin-engine P.35 had a 3-ton capacity for a 1000-kilometer range, while the three-engine P.39 had a 4-ton capacity for a 1800-kilometer range. The P.35 was to be able to fly on one engine only when empty, while the P.39 was conceived to be flyable on one engine only even fully loaded.
Externally the two designs were quite different from the Go 242/244, despite their general similar layout. The P.39 was conceivably larger than the P.35.
Here is a set of official Gotha documents presenting the P.39 project:
1°) P39-100: Three-view arrangement
2°) P39-101: Three-view arrangement in silhouette form
3°) P39-108: Development of the P.39 (from the DFS 230 through the Go 242, Go 244 and P.35)
4°) P39-109: Comparison between the Go 244 and the P.39
5°) P39-110: Comparison between the Go 244 and the P.39 (continued)
6°) P39-145: Fuselage overview
On top of this I'm adding:
7°) A zoomed-in view of the P.35 silhouettes
8°) A cleaned-up profile view of the P.39