Hexagonal bipyramid bipyramid has a plane of symmetry (which is horizontal in the figure to the right) where the bases of the two pyramids are joined. This plane is a regular hexagon. There are also six planes of symmetry crossing through the two apices. These planes are rhombic and lie at 30° angles to each other, perpendicular to the horizontal plane. It can be drawn as a tiling on a sphere which also represents the fundamental domains of [3,2], *322 dihedral symmetry: The hexagonal bipyramid, dt{2,6}, can be in sequence truncated, tdt{2,6} and alternated (snubbed), sdt{2,6}: The "hexagonal bipyramid", dt{2,6}, 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