Radius of Curvature Figure 1 — Comparison of Radii of Curvature showing small radius with high curvature vs large radius with low curvature. Figure 2 — The radius of curvature of a dome. Figure 3 — The side view and footprint of an oblate ellipse. Figure 4 — The radii of the oblate ellipse ranging from smallest at the edge (R1) to largest at the top of the dome (R4). Figure 5 — Side view of oblate ellipse at Monolithic. Figure 6 — Oblate ellipse with hanger door at Monolithic. Figure 7 — Ribs strengthening top of oblate ellipse dome at Monolithic. Figure 8 — A crenoshpere strengthened by ribs.