Submarines : Weapons of the Deep
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Submarines were one of the most feared weapons of the Great War.
Much like gas warfare, they were weapons that were only beginning
to be fully utilized. Submarines that worked had been around
since the early 1800's. At that time, however, they were little
more than small barrels that were weighted down to float just blow the
surface, so that they could be pedaled up to a wooden warship, and
drill holes to anchor explosives to the hull while the ship was docked
in port.
The first "modern" submarines were designed in the United States in the
1880's. The first successfully boat was built by John Holland, and
American naval engineer. His designed used water as ballast to
sink the ship, and compressed air to empty the ballast to allow a
submarine with controllable depth.
By the start of the Great War, submarine technology had greatly
improved. Submarines could go deeper (150 feet or so), and had
torpedoes and guns mounted on the deck to attack enemy ships. The
capability to run under water was quite an accomplishment, but the
submarines of World War One were not at all like submarines of today.
Submarines in the great war were very limited in their
capacity to
function underwater. Most were only rated to go 150 feet down or
so, and they needed to surface for air quite frequently.
Submarines used an oil-fired engine (gasoline or diesel) to power
the submarine. While running on the surface, there was plenty of
air to burn. Underwater, submarines needed to either burn air
from compressed air tanks, or run on battery power. Batteries
required recharging, and this mean that the submarine needed to come to
the surface to run the oil-fired engine to charge the batteries.
On the surface, submarines could be spotted from the air (using
balloons and blimps) or by nearby ships.