Abstract: A combustion chamber arrangement includes an annular outer and inner walls including at least one row of tiles. Each tile in the row of tiles has a rail extending towards and sealing with the outer wall and lip extending in a downstream direction from the row of tiles. The outer wall has a row of apertures to direct coolant onto the lips of the row of tiles. Each tile has a fastener positioned upstream of the rail and the fastener extends through a corresponding mounting aperture to secure the tile to the outer wall. The rail of each tile defines a plurality of slots with the outer wall and the slots are arranged in a region downstream of the corresponding fastener. None of the apertures in the row of apertures are in a region downstream of the tiles fastener. The arrangement reduces crack generation and propagation in the outer wall.