You also need to pay attention to make sure that you have enough overlap of the two sides of the "sky", so that the goose is 1/4" below the top of your finished flying geese unit. That's the seam allowance that will let you sew them together without cutting off the point.

I understand your frustration. I made a queen size quilt made of over 600 flying geese blocks so I experimented with lots of ways to make them. Check out Eleanor Burns on You Tube. It's the best, easiest, and accurate method AND you get 4 geese blocks when you're finished. Made the quilt go much quicker and took the stress off of having accurate blocks.

I find the most accurate way to make flying geese is to paper piece them. Works every time and is exact.

I bought a Deb Tucker's Wing Clipper ruler and have found that to be the most accurate way for me to make Flying Geese with the least waste.