Patent ID: 8418953

Claim:
A nacelle for a gas turbine engine, the nacelle comprising: an intake at the upstream end of the nacelle having, in flow series, an intake lip and a diffuser; wherein the diffuser has a main diffuser section that is bounded by an inner wall of the nacelle, the inner wall curving in an airflow direction of the engine and, on each longitudinal section containing the longitudinal axis of the nacelle, at the downstream end of the main diffuser section the inner wall having a curvature, whereby each circumferential position on the inner wall at the downstream end of the main diffuser section has the curvature defined by a respective radius of curvature, and one or more of said radii of curvature differs from the others of said radii of curvature, wherein around the circumference of the inner wall, a ratio of the largest radius of curvature to the smallest radius of curvature is at least 2; and an exhaust at a downstream end of the nacelle.