The above image shows a sketch in 3D. Not only is the aircraft presented in a three dimensional perspective, the sketch can be rotated as if it was a 3D model. To understand how this works watch the video below.
This amazing program named ILoveSketch lets you draw in 3D in a very clever way: it lets you define planes in which you can draw curves. It then helps you to construct vehicles or aircrafts by providing a mirror tool. There’s also a mechanism that smooths your curves.
Both programs could help product designers or car designers create concepts much faster.