Abstract: A composite component such as a fan casing liner panel for a gas turbine engine comprises an abradable layer and a layer. The layer is provided with a septum layer, to which the abradable layer is bonded. The septum layer is perforated by holes, which enable air to be extracted from the region between the septum layer and the abradable layer during the process of bonding the components together, for example by a vacuum bonding process.

Abstract: Provision of panels within casings can cause problems where retaining bolts require apertures in the casings, which in turn may reduce the structural strength of that casing. By providing a ring within the casing and appropriate retainer elements secured to that ring, which elements in turn appropriately present panels, it is possible to provide a casing assembly which avoids the necessity of drilling or otherwise forming holes in the casing. Dam elements can be provided at each end of the assembly to prevent axial movement and therefore retain panel position within the casing.

Abstract: A turbofan gas turbine engine (10) comprises a fan rotor (32) carrying a plurality of radially extending fan blades (34). A fan blade containment assembly (38) surrounds the fan blades (34) and the fan blade containment assembly (38) comprises a generally cylindrical, or frustoconical, metal casing (40). The casing (40) comprises an annular member (54) positioned axially upstream of the tip (37) of the fan blade (34). The annular member (54) extends in a radially inwardly and axially downstream direction from the metal casing (40) towards the tip (37) of the fan blade. A set of cassettes (120) carries fan blade track panels (71B, 71C, 71D). The cassettes (120) are secured to the metal casing (40) by axially extending members (124, 128) on the upstream and downstream ends (122, 126) of the cassettes (120) which locate on the annular member (54) and are secured to inserts (136) on the inner face of the casing (40).

Abstract: A turbofan gas turbine engine (10) comprises a fan rotor (32) carrying a plurality of radially extending fan blades (34). A fan blade containment assembly (38) surrounds the fan blades (34) and the fan blade containment assembly (38) comprises a generally cylindrical, or frustoconical, metal casing (40). The casing (40) comprises an annular member (54) positioned axially upstream of the tip (37) of the fan blade (34). The annular member (54) extends in a radially inwardly and axially downstream direction from the metal casing (40) towards the tip (37) of the fan blade (34). A set of cassettes (120) carries fan blade track panels (71B,71C,71D). The cassettes (120) are secured to the metal casing (40) by axially extending members (124,128) on the upstream and downstream ends (122,126) of the cassettes (120) which locate on the annular member (54) and are secured to inserts (136) on the inner face of the casing (40).

Abstract: A composite component such as a fan casing liner panel for a gas turbine engine comprises an abradable layer and a layer. The layer is provided with a septum layer, to which the abradable layer is bonded. The septum layer is perforated by holes, which enable air to be extracted from the region between the septum layer and the abradable layer during the process of bonding the components together, for example by a vacuum bonding process.

Abstract: Provision of panels within casings can cause problems where retaining bolts require apertures in the casings, which in turn may reduce the structural strength of that casing. By providing a loose or snug fit ring placed within the casing and appropriate retainer elements secured to that ring which in turn appropriately presents panels it is possible to provide a casing assembly which avoids the necessity of drilling or otherwise forming holes in the casing which may reduce structural strength. The rings, retainers and the panels do not need to be mechanically fixed to the casing although where possible a ring may be secured through bolts in areas of the casing where structural strength is less important. Where there is no bolting between the ring and the casing then dam elements can be provided at each end of the assembly to prevent lateral axial movement and therefore retain panel position within the casing.