An assembly for an aircraft propulsion system , comprising: a nacelle comprising an outer structure and an inner structure , a bypass flowpath formed by and radially between the outer structure and the inner structure ; the inner structure including a support structure , a first core cowl and a second core cowl ; the support structure including a plurality of first hinges , a plurality of second hinges , a plurality of longitudinal rails and a plurality of crossover rails spaced longitudinally along and connected to the plurality of longitudinal rails , each of the plurality of first hinges connected to a respective one of the plurality of crossover rails at a first distal end of the respective one of the plurality of crossover rails , each of the plurality of second hinges connected to a respective one of the plurality of crossover rails at a second distal end of the respective one of the plurality of crossover rails ; the first core cowl pivotally mounted to the support structure by the plurality of first hinges ; and the second core cowl pivotally mounted to the support structure by the plurality of second hinges , characterized in that : the support structure further includes a first mounting bracket , a second mounting bracket , an additional first hinge and an additional second hinge ; the first mounting bracket is mounted to and projects laterally out from a first of the plurality of longitudinal rails in a first lateral direction, and the additional first hinge pivotally mounts the first core cowl to the first mounting bracket ; and the second mounting bracket is mounted to and projects laterally out from a second of the plurality of longitudinal rails in a second lateral direction that is opposite the first lateral direction, and the additional second hinge pivotally mounts the second core cowl to the second mounting bracket . a nacelle comprising an outer structure and an inner structure , a bypass flowpath formed by and radially between the outer structure and the inner structure ; the inner structure including a support structure , a first core cowl and a second core cowl ; the support structure including a plurality of first hinges , a plurality of second hinges , a plurality of longitudinal rails and a plurality of crossover rails spaced longitudinally along and connected to the plurality of longitudinal rails , each of the plurality of first hinges connected to a respective one of the plurality of crossover rails at a first distal end of the respective one of the plurality of crossover rails , each of the plurality of second hinges connected to a respective one of the plurality of crossover rails at a second distal end of the respective one of the plurality of crossover rails ; the first core cowl pivotally mounted to the support structure by the plurality of first hinges ; and the second core cowl pivotally mounted to the support structure by the plurality of second hinges , the support structure further includes a first mounting bracket , a second mounting bracket , an additional first hinge and an additional second hinge ; the first mounting bracket is mounted to and projects laterally out from a first of the plurality of longitudinal rails in a first lateral direction, and the additional first hinge pivotally mounts the first core cowl to the first mounting bracket ; and the second mounting bracket is mounted to and projects laterally out from a second of the plurality of longitudinal rails in a second lateral direction that is opposite the first lateral direction, and the additional second hinge pivotally mounts the second core cowl to the second mounting bracket . <EOS>