GAS TURBINE ENGINE WITH CORE MOUNT

A gas turbine engine (10) for an aircraft comprises an engine core (11) comprising: a compressor system comprising a first, lower pressure, compressor (14), and a second, higher pressure, compressor (15); an outer core casing (76) surrounding the compressor system. The outer core casing comprises a first flange connection (60) arranged to allow separation of the outer core casing (76) at an axial position of the first flange connection (60), the first flange connection (60) having a first flange radius (104), wherein the first flange connection (60) is the first flange connection that is downstream of an axial position defined by the axial midpoint between the mid-span axial location on the trailing edge of the most downstream aerofoil of the first compressor (14) and the mid-span axial location on the leading edge of the most upstream aerofoil of the second compressor (15), and a front mount (50, 53a) arranged to be connected to a pylon (53). A front mount position ratio of:axial distance106between the first flange connection60and the front mount50,53afirst flange radius104is equal to or less than 1.18.