Fenian Ram - Design

Design

Fenian Ram's design was partly modeled on the Whitehead torpedo, and like it had cruciform control fins near the tail. The boat did not simply take on ballast until she sank like other contemporary submarines; she maintained a slightly positive buoyancy, and simply tilted her horizontal planes so that her forward motion forced her under.

Fenian Ram was armed with a nine-inch pneumatic gun some eleven feet long, mounted along the boat's centerline and firing forward out of her bow. It operated like modern submarine torpedo tubes: a watertight bow cap was normally kept shut, allowing the six-foot-long dynamite-filled steel projectiles to be loaded into the tube from the interior of the submarine. The inner door was then shut and the outer door opened by a remote mechanism. Finally, 400 psi (2.8 MPa) air was used to shoot the projectile out of the tube. To reload, the outer door was again shut and the water in the tube was blown into the surrounding ballast tank by more compressed air. It was powered by a 15 hp (11 kW) Brayton piston engine.