Momsen lung

Rebreather system for escaping sunken submarines

The Momsen lung was a primitive underwater rebreather used before and during World War II by American submariners as emergency escape gear. It was invented by Charles Momsen, who worked on it from 1929 to 1932. Submariners trained with this apparatus in an 80 ft (24 m) deep Escape Training Tank at New London, Mare Island, or Pearl Harbor. It was introduced as standard equipment on Porpoise (P)-class and Salmon-class boats.

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