This is a vehicle I created for Graphine, a newly founded company that specializes in HD texture streaming and compression for realtime rendering applications (e.g., games). They asked me to design and model a plane for a Pilotwings-type tech demo that utilizes large amounts of unique texture data for the landscape. Below are some of my initial terrain & aircraft sketches and some progress shots.
We decided to explore the twin fuselage approach a bit further and go for a hybrid of E and J, with slightly more surface area. Based on the last sketch I first did a quick digital sculpt to refine things from different angles and clarify some areas and then used that as a guide for the model. Those large round intake things at the wing bases didn't translate into 3D very well, so after a few attempts of simplifying I scrapped them completely. Once I had the main shapes in place I went back to Photoshop for more pondering & detail planning before finalizing the mesh.
[Update] The aircraft was briefly featured in Microsoft's Build 2013 keynote. There's also a detailed presentation from the event that you can watch here (demo footage starts around 26 minutes into the video): Massive Virtual Textures for Games: Direct3D Tiled Resources