Swift 3D can export 3D models and animations to 2D vector formats like SWF. You can even further edit it in your 2D application. For the last part of the video the helicopter is exported to SWF then imported into Toon Boom Animate library. It's rotor animation is done in swift and the movement of the helicopter is done using a peg layer inside Toon Boom. If you have any questions ask them in the comments.