§25.1167 Accessory gearboxes

For aeroplanes equipped with an accessory gearbox that is not certificated as part of an engine – (a) The engine with gearbox and connecting transmissions and shafts attached must be subjected to the test specified in CS–E 160 and CS–E 740, as applicable. (b) The accessory gearbox must meet the requirements of CS–E 80 and CS–E 590, as applicable; and (c) Possible misalignments and torsional loadings of the gearbox, transmission, and shaft system, expected to result under normal operating conditions must be evaluated.