A mounting device for aircraft supply systems comprises a cross member and at least one support module including a body having a shape complementary to that of a cross member. The attachment comprises a housing which is secured in position on the housing so that driving movement transmitted from the driving shaft does not move the housing. The circuit board includes a plurality of switches. Each worker queue corresponds to a different one of a plurality of logical central processing units. Each bin includes a dispenser coupled to the controller for dispensing the packaged pharmaceuticals therefrom in response to a dispense signal sent from the controller. Accordingly, engine brake is used effectively, and the brake can be miniaturized.