An unloading system comprises an upper-opening chamber for receiving airplane-derived refuse; a chute; a chute-connected safety gate which is settable in falling preventing relation with respect to an access door of an airplane from which the refuse is unloadable into the chute and to the chamber; and an air brake assembly for immobilizing the safety gate when the chute ceases to be vertically displaced. A compacting system comprises a main platen mount with an occluding surface for occluding the opening; an auxiliary platen mount for movably supporting the main platen mount; a holder assembly underneath the auxiliary platen mount; and force transmitting elements always retained within a compaction chamber interior. The main platen mount is linearly driven between a first position completely forwardly of the opening and a second position at which the opening is completely occluded, and is additionally driven to discharge the received refuse. Methods are also disclosed.