Swede Momsen: Diving & Rescue - Momsen Lung

Development of submarine escape devices was spurred on by controversy surrounding the sinking of the submarine S-4 in December 1927. One such device is the Submarine Escape Lung, known as the Momsen Lung, which was developed by then Lieutenant Momsen, Chief Gunner Tibbals and civilian Frank Hobson.

The Momsen Lung was an oblong rubber bag that recycled exhaled air. The lung contained a canister of soda lime, which removed poisonous carbon dioxide from exhaled air and then replenished the air with oxygen. Two tubes led from the bag to a mouthpiece: one to inhale oxygen and the other to exhale carbon dioxide. The lung hung around the neck and strapped around the waist. Besides providing oxygen for the ascent, the lung also allowed a Submariner to rise slowly to the surface, thus avoid "the bends."

The device proved successful when eight Submariners used their Momsen Lungs to reach the surface from the USS Tang (SS-306), which sunk in 180 feet of water in the East China Sea in October 1944. Of the eight, five survived a night at sea, only to be taken prisoner.

Today, other methods, such as the Stanke Hood or free ascent, are used to get Sailors to the surface from a sunken submarine.