A hydraulic circuit for prevention of inadvertent weapons launches in which a hydraulic firing valve provides hydraulic pressure to a backup select valve rather than the backup select valve receiving hydraulic pressure directly from a ship supply header. This hydraulic pressure shifts the backup select valve to allow hydraulic pressure to pass to a mode select control valve that actuates a controllable air-firing valve, until a hydraulic firing valve for the weapon is opened. The backup select valve actuation can only occur with the initiation of the hydraulic firing valve. Only after the hydraulic firing valve is open, does the backup select valve initiate hydraulic pressure to the mode select control valve thereby preventing hydraulic actuation of the backup select valve.