cut parts from...but that is not a sport plane

A metal sport plane can
be built very very well with basic sheet metal tools. The high dollar
stuff would be a waste of money unless you needed production speed of an
automobile assembly line.
I've never built a plastic injection mold, but I've built airplanes
That's exactly the point, we're talking about production speeds. The
equipment you're talking about will not churn out a finished plane every 2
minutes at an affordable price.
I'm talking about CNC machines in cells with robots, and stamping machines,
and injection molds.