I recently bought a Taranis transmitter and had the first flight with one of my planes, a simple flying wing.
With the conversion to Taranis, some of the aerodynamic trims changed and after a hand launch the wing required up elevator trim.
I suppose I may have been unfamiliar with the feel of the Taranis: Instead of adjusting the elevator trim tab I pulled down on the on/off switch and turned the transmitter off!
I had a large degree of pucker factor when I detected that I no longer had control of the plane. But right after that realization sunk in the plane leveled out and began a circle out over the field.
Turns out the plane went into short failsafe CIRCLE mode, and then long failsafe RTL mode and was circling around the rally point I had added in anticipation of a short mission. As I contemplated how long it would circle until the battery ran out I realized the transmitter was turned off.
I turned the transmitter back on, switched to manual mode, regained control and brought the plane in without further drama.
That's a gutsy fail-safe test!
Fortunately I set the failsafe strategy before the first flight.
Thanks ArduPlane engineers for a good job.