The invention relates to an airship comprising a flexible envelope having at least one adjustment region provided with two longitudinal adjustment elements mounted in opposition and mobile in relation to each other between a maximum distancing position and a minimum distancing position, the two longitudinal adjustment elements being connected to each other by a group comprising a plurality of cables crossing the inner space of the envelope, each of the cables cooperating with a plurality or tightening points provided along each longitudinal element. The cables are connected to at least one tightening module that can exert a tightening or loosening action on the cables and thereby bring the longitudinal adjustment elements closer together or move them further away.