Section 25.1167 - Accessory gearboxesFor airplanes 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 tests specified in § 33.49 or § 33.87 of this chapter, as applicable;(b) The accessory gearbox must meet the requirements of §§ 33.25 and 33.53 or 33.91 of this chapter, 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.Amdt. 25-38, 41 FR 55467, Dec. 20, 1976