https://www.ebay.com/itm/40271384237...d2e50c37173811

How about just scale this up a bit.
Already available technology , it works great!
Available right off the shelf.
No fire problem.
No carbs or FI to fiddle with.
I think you can buy a folding nose prop today.
Just run a piece of 6" PVC under your seat run the rubber band nose to tail and wind it up.
Nick
T