Christian Lambertsen, Inventor of Scuba Precursor, Dies at 93

By Dennis Hevesi
When American commandos slipped into the sea off the coast of Burma in the last months of World War II and swam underwater to attach explosives to Japanese vessels, Capt. Christian J. Lambertsen often led them. After all, he had trained them to dive and had invented the breathing device that allowed them to stay below the waves.

Christian J. Lambertsen invented an underwater breathing system that was used by Navy commandos during World War II. “He wasn’t someone to let someone else do it,” recalled Walter Mess, who had been commander of a near-silent 85-foot vessel that ferried the divers, usually in the dark, within 2,000 feet of shore. “Sometimes they were recon missions, sometimes to bring back downed airmen.”

Captain Lambertsen, an Army doctor, did not have to go on those missions. His assignment was to train members of the maritime unit of the Office of Strategic Services to use the device he had invented while in medical school. The Lambertsen Amphibious Respiratory Unit, or LARU, made those covert operations possible.

Dr. Lambertsen, an expert in respiratory medicine at the University of Pennsylvania, died on Feb. 11 at his home in Newtown Square, Pa., his son David said. He was 93. 

The LARU is considered a precursor to modern scuba technology, and Dr. Lambertsen is widely believed to have coined the word scuba, an acronym for self-contained underwater breathing apparatus. 

Although he started tinkering as a teenager, Dr. Lambertsen fully developed a closed-circuit, pure-oxygen rebreather in 1939 while a student at Penn’s School of Medicine. Using filters from anesthesia equipment, he built a back-mounted tank from which the diver inhales pure oxygen. Carbon dioxide in exhaled breath is then scrubbed out through a chemical filter and returned to the diver as purified oxygen.  “It means that it doesn’t emit bubbles, so if you are swimming under a ship there are no telltale bubbles,” said Tom Hawkins, a historian for the Naval Special Warfare Foundation in Virginia Beach.  When Dr. Lambertsen demonstrated the LARU to the Navy in 1939, the Navy showed little interest because its deep-water salvage missions required helmeted divers to breathe through long hoses tethered to boats. But the O.S.S, a forerunner of the C.I.A., saw its stealth possibilities.

Once Dr. Lambertsen graduated from medical school in 1943, he joined the Army and was assigned to the O.S.S. as lead trainer for its underwater operations.  After the war, Dr. Lambertsen joined the faculty at the University of Pennsylvania, where he converted an abandoned altitude chamber into a laboratory that was soon drawing experts and students interested in undersea and aerospace environmental physiology.

By 1948 the Navy had adopted Dr. Lambertsen’s improved version of the LARU and hired him to train its divers.

“The naval special warfare community and the special operations community recognizes him today as the father of U.S. combat diving and swimming,” Mr. Hawkins said.  

Dr. Lambertsen taught at Penn for more than 40 years. In 1968, under his direction, the university established the Institute for Environmental Medicine, which has conducted multidisciplinary studies of oxygen toxicity, diving-related diseases and aerospace medicine. 

Christian James Lambertsen was born in Westfield, N.J., on May 17, 1917, one of four children of Chris and Ellen Lambertsen.

Dr. Lambertsen’s wife, the former Naomi Hill, died in 1985. Besides his son David, he is survived by three other sons, Christian Jr., Richard and Bradley, and six grandchildren.

After graduating from Rutgers in 1938, Dr. Lambertsen began his medical studies at Penn and was soon delving deeper into a childhood fascination.

“He spent a lot of time on Barnegat Bay with his grandfather collecting clams and started wondering how to go deeper underwater,” his son David said. “He had his cousin in a rowboat using a bicycle pump and a hose to pump air 15 feet down to him.”