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Earlier this year, on April 15, 2015, I attended a lecture at the Florida Institute for Human and Machine Cognition (IHMC) in Ocala. The speaker was Jay Dean, Ph.D., director of the Hyperbaric Biomedical Research Laboratory and Professor in the Department of Molecular Pharmacology & Physiology, Morsani College of Medicine at the University of South Florida.
Dr. Dean’s topic for the evening was “Your Body in Flight During World War II: How American Physiologists Learned to Protect the Health of Airmen in the World’s First High Altitude, High Speed Air War.” My interest in this topic was, of course, what this meant to my dad, George Edwin Farrar, a waist gunner on a B-17 crew who routinely flew missions over Germany from his base in Grafton Underwood, England.
Anoxia is the absence of oxygen. The human condition resulting from the lack of oxygen in the blood stream is called hypoxia. High altitude flight in WWII would not have been possible without the creation of the oxygen mask as bombers in those days were not pressurized.
WWII was the world’s first high-speed, high-altitude air war. As such, Dr. Dean noted that flying in unpressurized B-17’s, once the airmen were above 10,000 feet, the earth’s atmosphere could turn deadly. As altitude increased, barometric pressure decreased and oxygen levels dropped. Once an altitude of 10,000 feet was reached, the airmen would start using oxygen, except for on night missions, when they would start their oxygen while still on the ground as it improved their night vision.
At sea level, blood saturation with oxygen is 95% and the airmen would experience normal actions and judgment. By 11,000 feet, oxygen in the blood is reduced to 85%, resulting in poor judgment without awareness, as if after a few drinks. At 13,000 feet, it is down to 80% and mental errors and possibly tremors or shakiness occurs. At 18,000 feet, blood saturation with oxygen is at 70%, resulting in a danger of collapse, or passing out. Anything above 20,000 feet would not support life for very long.
A typical mission would be flown at altitudes of 20,000 to 35,000 feet or higher, requiring the use of oxygen by the air crew to survive. In addition to the lack of oxygen, the temperatures at these altitudes were extreme.
Dr. Dean explained that in the air war over Europe, at 23,450 feet, the temperature inside a B-17 would be around minus 13.5°F, in the warmer month of June. In January, it would only be around minus 36.4°F. Go up in altitude to 30,100 feet and the June temperature would drop to minus 39.5°F; in January, minus 60.9°F.
In addition to the possibility of frostbite at those temperatures, ice buildup inside the oxygen masks was another consequence of the brutal cold. While trying to fly the ship, or man their guns, bomb sights, and other equipment, the air crew had to make sure they were getting enough oxygen and continually knock the built-up ice from their oxygen masks.
In this photo, Chester Rybarczyk, navigator of the John Oliver Buslee crew, 544th Bomb Squad, 384th Bomb Group of the 8th Air Force is shown wearing his oxygen mask on a mission over France.
To view Dr. Dean’s entire lecture, click here.
I will discuss the electric flight suits in a future post.
© Cindy Farrar Bryan and The Arrowhead Club, 2015