I was inspired to try this tail first takeoff after watching my seven year old son, José Luis, playing with a chuck glider. He launched the chuck glider tail-first and inverted, and it did a half flip and then flew away upright.
I figured why not? Here I am performing it with my 17oz ultralight Le Fish. I named the trick the J-Flip in honor of my son.
Update: I have been informed that Marcel Guwang, designer of the MG05 airfoil used on the Voltij by Aeromod (which was my first true aerobatics glider and one I still love dearly) has been doing this kind of tail-first takeoff since around 1999 in Toulouse with the Voltij and Minij gliders. Very cool!
So I want to make it clear that my own inspiration comes from the example of my son, and, as I don't know what Marcel called this trick (if he even gave it a name), I will continue to refer to it as a J-Flip in my son's honor, though of course it's obvious that this trick has most likely been done many times, by many people, all over the world for a long time now. But I will say it feels good to be in the company of someone I admire as much as Marcel Guwang! :)