The report of this accident can be found here:
https://data.ntsb.gov/carol-repgen/a...ort/106317/pdf
This is worth the read, both from the perspective of flight test discipline, pilot familiarity with aircraft avionics systems, and the factor of the Garmin Electronic Stability and Protection (ESP) system supplementing control of the airplane while the unaware pilot was stall testing, and recovering. Exactly this has also happened to me during recent flight testing, deliberately stalling the airplane, unaware that this system was operating in the background I managed to not overspeed the plane as I recovered, but it was a messy recovery, while I figured out that my test subject airplane also had this system. I'll be reviewing this report with great interest, but the "background" ESP system is a factor which cannot be overlooked here. The airplane I've been testing and will approve (other modifications) is going to have an approval with warnings about the ESP system operation.
Complex automation concerns me a little, with the need for more pilot familiarity. A background system which the pilot may not even know is there, supplementing control of the airplane without the pilot knowing, really worries me!