Abstract: An apparatus and method for the disassembly of an ultra high bypass turbine engine having an outer engine portion and an inner engine portion. A plurality of fan blades and acoustic panels are removed from the inner portion of the engine. The outer portion of the engine which includes a plurality of fan outlet guide vanes and fan casing are disconnected from the engine and axially removed. Certain outer portions of the engine including a hinged thrust reverser and hinged fan cowling may be coupled to an aircraft pylon and used interchangeably with replacement engines.

Abstract: A gas turbine engine has a core frame separable from a vane frame for removably attaching the vane frame to a core structure through a mid ring. The mid ring includes an annular forward panel and an annular aft panel, each of which has a radially outer flange and a radially inner flange. The inner flanges are welded to the core frame and the outer flanges are bolted to the vane frame. A plurality of circumferentially spaced stiffeners extend between the forward and aft panels, with each of the stiffeners including a pair of stringers extending diagonally across the stiffeners. Panels may be incorporated with the stringers between the triangular shaped areas adjacent the forward and aft panels of the stiffener. The bolted connection between the mid ring and the vane frame includes a plurality of tongue and groove joints formed in the flanges of the mid ring and vane frame. The tongue and groove joints provide additional radial support for the core engine within the vane frame.