This is a flight demo of the recently released MatrixPilot 5.0flying the helical Turn algorithms by William Premerlani.
MatrixPilot is a relatively small open source GPL v3 licensed Autopilot, which provides a platform for DIY enthusiasts to experiment with new algorithms and ideas. It does not have a large user base, partly because any change in it's configuration requires a recompilation of the code. The official announcements for this 5.0 release is on the uavdevboard discussion list.
Comments
@Vladimir: It's a "Tercel" by Bridi Aircraft Designs Inc, that I made while on trip to California in the late 1980s.
Pete, what a plane you hold on awatar photo? :)))