The Brandtaucher ("Incendiary Diver") Submarine
Incendiary ships were a well known concept in blockade-breaking. A ship was loaded with explosives and set free to drift into the enemy fleet, exploding at contact. The incendiary diver was planned to work on a similar principle: It would dive under an enemy vessel, fix an electrically triggered mine to its hull and escape, igniting the mine from a safe distance. The more or less same technique was employed by all military submarine designs of that time, like Julius Kröhl’s Explorer, the U.S.S. Alligator by Brutus de Villeroi and the famous Hunley, which became the first submarine to sink an enemy vessel.
After the model of the submarine, built by Bauer himself, proved to be working, he was granted enough money to build a full scale submarine. But the military authorities still were largely against Bauer’s plan and forced Bauer to change his designs in order to reduce costs.
The finished Brandtaucher, built by August Howaldt of the later Howaldtswerke was 28 feet long, weighing about 70,000 pounds. As at that time no suitable mechanical power system was available the submarine was powered by two sailors turning a big tread wheel with their hands and feet. The third crew member, the captain, was positioned at the stern of the submarine. His job was to operate the rudders and other controls. Having arrived under the target ship the captain would reach out through a gutta percha (rubber) glove fixed to an opening of the hull, grab the mine located within reach on the hull of the submarine and fix it on the target.
Had the Brandtaucher been built according to Bauer’s original designs, it would have achieved submersion by filling several tanks with sea water. But in the changed version the vessel itself was to be partly flooded with water, thus rendering the submarine dangerously unstable. Also the thickness of the hull and the dimensions of the pumps had to be greatly reduced.
First trials of the submarine took place in December 1850. Although Bauer wanted to make several improvements of the submarine, the military ordered a public show on 1 February 1851.
This public demonstration almost ended in a disaster. After reaching a depth of 30 ft the craft began to lay down by the stern. As the submarine sank down the thin walls could not take the water pressure any more and started to crack. The water pressure proved too much for the weak pumps and the propeller wheel was damaged when the vessel began to keel over. The submarine slowly sank to the ground of the Kiel harbour. For six hours Bauer and his sailors had to wait inside the sunken craft, until enough water had seeped in. This increased the air pressure inside the submarine and finally allowed the men to open the blocked hatchway. As the submarine stayed buried on the ground of the sea, its crew came to the surface unharmed. This was the first submarine escape to be witnessed and reported.
The sunken submarine was raised in 1887 and can now be visited at the museum of military history at Dresden, Germany (Militärhistorisches Museum der Bundeswehr)
Read more about this topic: Wilhelm Bauer