A mounting assembly for securing a passenger seat in an aircraft, the mounting assembly comprising: a beam comprising: a flat upper surface; and a plurality of holes spaced apart from one another along a length of the beam and extending through the flat upper surface; an adaptor comprising: a channel extending longitudinally along the adaptor; a bottom thickness; a pair of lips partially enclosing an upper side of the channel; a longitudinal slot formed between the pair of lips; a plurality of cutouts positioned along the pair of lips and defining openings in the slot; and a plurality of apertures each extending through the bottom thickness, the plurality of apertures arranged along a length of the adaptor so as to directly correspond in location with the plurality of holes of the beam when the adaptor is aligned with the beam; a plurality of fasteners extending through the beam and the adaptor via the plurality of apertures and the plurality of holes so as to secure the adaptor to the beam when the adaptor is aligned with the beam; and a fitting comprising a portion of a passenger seat of an aircraft, the fitting being received by the adaptor so as to secure the passenger seat relative to the beam when the adaptor is secured to the beam, characterized in that the adaptor further comprises a corrosion-inhibiting coating so as to prevent a contact between material of the adaptor and material of the beam that could otherwise facilitate galvanic corrosion. a beam comprising: a flat upper surface; and a plurality of holes spaced apart from one another along a length of the beam and extending through the flat upper surface; a flat upper surface; and a plurality of holes spaced apart from one another along a length of the beam and extending through the flat upper surface; an adaptor comprising: a channel extending longitudinally along the adaptor; a bottom thickness; a pair of lips partially enclosing an upper side of the channel; a longitudinal slot formed between the pair of lips; a plurality of cutouts positioned along the pair of lips and defining openings in the slot; and a plurality of apertures each extending through the bottom thickness, the plurality of apertures arranged along a length of the adaptor so as to directly correspond in location with the plurality of holes of the beam when the adaptor is aligned with the beam; a channel extending longitudinally along the adaptor; a bottom thickness; a pair of lips partially enclosing an upper side of the channel; a longitudinal slot formed between the pair of lips; a plurality of cutouts positioned along the pair of lips and defining openings in the slot; and a plurality of apertures each extending through the bottom thickness, the plurality of apertures arranged along a length of the adaptor so as to directly correspond in location with the plurality of holes of the beam when the adaptor is aligned with the beam; a plurality of fasteners extending through the beam and the adaptor via the plurality of apertures and the plurality of holes so as to secure the adaptor to the beam when the adaptor is aligned with the beam; and a fitting comprising a portion of a passenger seat of an aircraft, the fitting being received by the adaptor so as to secure the passenger seat relative to the beam when the adaptor is secured to the beam,