Hexagon of the circumscribed circle, which equals formula_1 times the apothem (radius of the inscribed circle). All internal angles are 120 degrees. A regular hexagon has 6 rotational symmetries ("rotational symmetry of order six") and 6 reflection symmetries ("six lines of symmetry"), making up the dihedral group D. The longest diagonals of a regular hexagon, connecting diametrically opposite vertices, are twice the length of one side. From this it can be seen that a triangle with a vertex at the center of the regular hexagon and sharing one side with the hexagon is equilateral, and that the regular hexagon can be
A Plane Is Born Mark visits the Popular Flying Association Rally at Cranfield to see some of the 3000 or so home-built and vintage aircraft that have flown in for the weekend. He talks to Graham Newby, the Chairman of the PFA and the Editor of Flyer Magazine who takes him through the perils and pit falls of building his own plane. - Test Flight Mark travels to the Europa Factory in North Yorkshire where after seeing all the components that go into making a kit, he takes a test flight with Technical Director Andy Draper. In part 2, he starts his private pilot