Two of the most popular and famous military air show groups have been the U.S. Navy’s Blue Angels and the U.S. Air Forces’ Thunderbirds. The average density of the boat must be less than the density of the water in order for the boat to stay afloat. A horse and some sort of wheeled cart or buggy is one of the oldest forms of transportation used, since the invention of the wheel! The first fixed wheels were used on carts in around 3500 B.C. Steam engines were not developed until around 1700. That and much more will be discussed during this session.