On this day - 21 June 1896 – Charles Momsen, American admiral, inventor of the Momsen lung was born (d. 1967).
Charles Bowers Momsen (June 21, 1896 – May 25, 1967), nicknamed "Swede", was born in Flushing, New York. He was an American pioneer in submarine rescue for the United States Navy, and he invented the underwater escape device later called the "Momsen lung", for which he received the Navy Distinguished Service Medal in 1929. In May 1939, Momsen directed the rescue of the crew of Squalus (SS-192)
In addition to the Navy Cross once and the Legion of Merit with two Gold Stars (to show repeat awards) and "V" device, Momsen earned the Navy Distinguished Service Medal, Army Distinguished Service Medal, Navy Commendation Medal with "V" device, World War I Victory Medal with escort clasp, American Defense Service Medal with Fleet Clasp, American Campaign Medal, Asiatic-Pacific Campaign Medal with four service stars, World War II Victory Medal, Navy Occupation Service Medal, National Defense Service Medal, Philippine Liberation Medal with one bronze star and the Submarine Warfare insignia.
It was aboard S-1 Momsen's attention became drawn to the urgent need for a way to rescue trapped submariners.
On September 25, 1925, S-1's sister ship, S-51 (SS-162), collided with freighter City of Rome and sank in 130 feet (40 m) of water. Momsen was ordered to take S-1 to search for the crippled submarine. S-1 found the oil slick marking the spot where S-51 had sunk, but without any sonar, there was no way for his crew to locate her on the bottom, nor was there a way for trapped crewmen to escape.
Momsen began to look for ways to rescue submariners. He conceived a diving bell, which could be lowered to a submarine in distress, mated to an escape hatch, and opened to allow trapped submariners to climb in. A watertight seal to the submarine could be achieved by placing a rubber gasket around the diving bell's bottom and reducing the air pressure once the bell was over the escape hatch. Then, the hatch could be opened, and the trapped submariners could climb aboard.
Shortly thereafter, in December 1927, another submarine, the S-4 (SS-109), sank off Cape Cod. All forty of her crew died. Six sailors survived three days in the forward torpedo room, but had no way to escape.
After the S-4 incident, Momsen began working on a device to help trapped submariners escape safely to the surface. Officially called the Submarine Escape Lung, it consisted of an oblong rubber bag that recycled exhaled air. The press enthusiastically received the device and they dubbed it the "Momsen lung", a name that stuck.
The Momsen lung contains a canister of soda lime, which removes poisonous carbon dioxide from the exhaled air and then replenishes the air with oxygen. Two tubes lead from the bag to a mouthpiece: one with which to inhale air and the other to with which to exhale spent air. The device hangs around the wearer's neck and is strapped around the waist. Besides providing oxygen for the ascent, it also allows a submariner to rise slowly to the surface, thus avoiding embolisms.