The group where you can share your artwork, concept art, drawings, and designs for use by 3D artists.
28 aircraft designs including variations, entirely in the public domain. Free to use for any purpose so commercial assets (models, animations, etc.) based on those designs can be sold. Drawn by Blaze45 (SensouSanka) and commissioned by feillyne. Made in late 2013, released to the public domain March 22nd, 2016. Originally drawn for an RTS/RPG hybrid game where you would command and manage an airborne faction roaming around a legendary/fantasy-like continent in a mixed sci-fi/fantasy setting; vast customisation, karma consequences and other features were planned. (Had to discontinue that project.)