Complex sentence: In the early stages of training the vessel is fitted with a training warhead, with no explosives, telemetry equipment and an emergency blowing chamber should the trainee dive to a dangerous depth.
Split into simpler sentences: In the early stages of training, the vessel is fitted with a training warhead. This has no explosives and in their stead are telemetry equipment and an emergency blowing chamber should the trainee dive to a dangerous depth.