A "Park Avenue" boom allows for the same aerodynamic curvature as a flexible boom, but is a rigid construction with a flat surface on top. Instead of being fastened directly to the boom, the foot of the sail is fastened to fittings that slot into grooves that run transversely across the boom. As these fittings move within their grooves, the foot of the sail is free to curve. It takes its name from the great width of such a boom fitted to the yacht Enterprise for the 1930 America's Cup competition, a hyperbolic comparison to the width of Park Avenue. See also Wishbone boom Bibliography References Further reading Sailboat components Sailing rigs and rigging Nautical terminology