Spiral Stability and the Bowl Effect
Introduction. Part One of this article described the characteristics required for an airplane to achiceve full spiral stability. This month we'll explore the subject a bit more deeply with a look at flight dynamics during circling flight. In particular, Part Two concerns itself with precisely how spiral stability is affected in spirally unstable aircraft. The material that follows will be difficult to understand completely without having read Part One.
Table Saw Accessory Tools
Top: Simple fence modifications improve the stock unit. The clamp at the far end of the fence (A) holds the fence steady under side force. The addition of a piece of plywood at the side of the fence (B) prevents thin material from slipping under the fence. Left: The basic cutoff tray is made from 1/4-in. birch ply with 3/16 ply runners. Asymmetry allows short pieces to be cut off from well-supported stock or extra-long pieces to be cut with a fixed stop (see the next picture). Right: The cutoff tray in position on the saw. Note how the runners (A) fit into the slots in the table top. Adjustable stop (B) is held in position with a C-clamp. This stop allows repetitive, precise cutting of rectangular pieces such as shear webs and bulkheads. These accessories are used on a Dremel saw but should be adaptable to other makes.
