FRONT SECTION STIFFNESS RATIO

A gear reduction (104) reduces a speed of a fan rotor (106) relative to a speed of a fan drive turbine. A rigid connection between a fan case (108) and an inner core housing includes a plurality of A-frames (116) connected at a connection point (122) to the fan case (108). Legs in the A-frames (116) extend away from the connection point (122) in opposed circumferential directions to be connected to a compressor wall (111) of the inner core housing. The rigid connection also includes a plurality of fan exit guide vanes (114, 129) rigidly connected to the fan case (108). A lateral stiffness ratio of the lateral stiffness of the plurality of fan exit guide vanes (114, 129) and a lateral stiffness of a combination of the plurality of A-frame, the compressor wall (111), and a fan intermediate case (210) which is forward of the low pressure compressor (44, 112) being greater than or equal to 0.6 and less than or equal to 2.0.