A fastener assembly for attaching a floor panel to an airframe is disclosed. The fastener assembly includes a collet, a pin, a capnut, and a subplate. The collet comprises at least one tang, extending from a cylindrical collar that defines a collet aperture. An external thread is formed on the collar, and a tab is formed on a distal end of the tang. The collet tang extends through a floor panel aperture, a subplate aperture, and an airframe aperture, and may interact with a subplate asymmetry. The capnut is screwed onto the collet, such that the pin is forced to slide along the collet tang and the tab is engaged with the airframe.