One day my daughter, Susan, came home from school and said “Dad, can we build a plane?”... Now, I like to think that I am good at paper planes, even if I do have only one shape...the dart. “No problem” I replied, reaching for a sheet of foolscap. “No” said Susan, “I mean a real one, a big one.” And she really did mean a really big one. Susan had volunteered that Arnold School would enter into the Blackpool Round Table “Birdman” competition. This would entail making some sort