It finally flew!!!!!
New design of my hot air balloon
Third attempt:
As you guys can see, I completely redesigned my hot air balloon's frame. I replaced the previous stick frame with a metal wire frame, which is more challenging to make. I also reduced the length of my fire source from the balloon to prevent the plastic bag from burning. So after six total attempts at getting the hot air balloon to fly, it finally did. After all the hardships, times, and coins that I've put into this project, I was finally satisfied with the result that I got from my hot air balloon.