A launcher includes a plurality of launch tubes (110) for stowing and launching a plurality of air vehicles. A central air manifold (310) is operatively connected to an air storage tank (150); a first launch tube air manifold (320) is operatively connected to a first group of the launch tubes (110) and operatively connected to the central air manifold (310). The first launch air manifold (320) has a separate port corresponding to each launch tube (110) of the first group of launch tubes. A release valve mechanism (360) is removably mounted in one of the ports (355) of the first launch tube air manifold (320), the release valve mechanism (360) controlling the passage of launch air between the first launch tube air manifold (320) and the launch tube corresponding to the port (355) in which the release valve mechanism (360) is mounted. A plug (350) is removably mounted in each of the ports (355) not occupied by the release valve mechanism (360).
