The next 6 of September is the 50 Th aniversary of the frist flight of the Evans VP-1 "Volksplane"
http://www.evansair.com/
https://youtu.be/pQIaCvfeuOY
After half century, she's still in "production". Congratulations Mr. Evans!!! It's the better tribute to your dad's memory.
Plans, handbooks and another information are available to purchase at http://www.evansair.com/store.html
I believe she's a very interesting subject to build in FlightGear.