An aircraft pylon comprising a structure covered by a fairing. The structure includes at least one void bounded by a peripheral edge. The fairing includes at least one removable panel connected to the structure around the void and having an inner face oriented towards the structure. The structure includes at least one seal connected to the structure so as to be slightly compressed against the inner face of the removable panel. The seal extends over at least a lower portion of the peripheral edge so as to retain a fluid located below a sealing horizontal plane while ensuring ventilation beneath the fairing.