GAS TURBINE ENGINE WITH IMPROVED BENDING RESISTANCE

A gas turbine engine (10) for an aircraft comprises: an engine core (11) comprising: a compressor system comprising a lower pressure compressor (14) and a higher pressure compressor (15); and an outer core casing (70) surrounding the compressor system. The gas turbine engine further comprises a fan (23) located upstream of the engine core (11), the fan comprising a plurality of fan blades (23a) and having a fan diameter (112). The outer core casing comprises a first flange connection (60) having a first flange radius (104). A fan diameter ratio of: