Signs of danger – at 80,000 feet

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Signs of danger – at 80,000 feet

Dan Fluke, an airline pilot and 2009 graduate of UND Aerospace, always knew he wanted to fly. He also knew he wanted the best training available and all the safety courses available.

Which is why he enrolled at UND, and as part of his training, took Dr. Warren Jensen's altitude chamber course.

Recently, while flying a Canadair CRJ commuter jet with 40 passengers aboard, Fluke noticed a familiar and ominous sensation – a numbing feeling, a kind of tingling, that he recognized only because of his UND altitude chamber training and also because he had trained in UND's CRJ simulator.

"I knew what it was right away," said Fluke, who also runs a business in Florida, writing and publishing aeronautical training guides. "That sensation is what triggered me to look at the indicates, which told me that the aircraft, in fact, was depressurizing. It all rung a lot of bells for me, back to my training at UND. I went for my (oxygen) mask. We had to make a quick decision to make a descent to the closest airport."

"Basically what you get is a sensation, happening at your core and progressing outward toward your arms," said Fluke who was featured in the most recent UND "More than Beads and Feathers" campaign, which features notable American Indian students, faculty and alums. "You know to go for the mask first rather than fumble with the instrumentation or worry about other things. You want to get ahead of the situation."

It only takes a few seconds for the heads-up – if you know what you're feeling. And in an airplane, those few seconds spell the difference between getting back safely – or not.

We're talking decompression – one of the things the flight attendants or video tell you about when they're demonstrating the deployment and use of those bright yellow oxygen masks.

"It can happen real fast," said Jensen, a flight surgeon and Chester Fritz Distinguished Professor of Aviation in the John D. Odegard School of Aerospace Sciences. Jensen also runs the school's altitude chamber, where students learn how to deal with decompression and hypoxia--a condition that occurs when the body is deprived of oxygen, such as when an airplane loses cabin pressure.

"You want to deal with it before the hypoxia impairs you," said Jensen, who in 2012 ran more than 200 altitude chamber classes with 850 students. "The goal of our altitude chamber training here is to teach students to recognize the symptoms of hypoxia – and they're different for each person – and to deal with them immediately."

Jensen, himself a UND alumnus and an Air Force veteran, earned a master's in aerospace medicine from Wright State University in Dayton, Ohio, in 1993. Today, he serves as UND Aerospace director of aeromedical research and as its flight surgeon.

Decompression in an aircraft at altitude – and the resulting hypoxia for anyone aboard – can be fatal, as was likely the case with the Lear 35 that crashed in South Dakota with famed golfer Payne Stewart, friends and crew aboard. As experts such as Jensen attest, hypoxia can quickly lead to confusion and blackout, but not if the crew has been trained to recognize what's going on and takes appropriate action immediately.

UND's altitude chamber training works.

The altitude chamber – a unique asset at the University – is used for both aviator training and research, including work with Fortune 500 corporate pilots. It's capable of simulating altitudes in excess of 80,000 feet and is used to teach flight crews the physiological effects of high altitude flight in a safe training environment. Subjects presented in the Aerospace Physiology courses include hypoxia, hyperventilation, cabin decompression issues, visual and spatial disorientation and several other related topics.

Jensen's research areas include human flight performance, decision-making in emergency settings and oxygen delivery systems. He also teaches courses in human factors in aviation and aerospace physiology.

Unmanned aircraft systems (UAS) – for which the aerospace program at UND has become a world leader – is another research area in which Jensen has begun to collaborate with others on campus.

Jensen also lends his expertise to the North Dakota Air National Guard, determining whether a pilot is fit to fly. As a pilot, a doctor and a diabetic, Jensen knows all too well that pilots don't like to be grounded, even if there's a good medical reason they should be.

Jensen is an academic advisor to 25-30 aviation undergraduate and graduate students. He is the aviation medical advisor to students, flight instructors and faculty for medical certification issues.

The UND altitude chamber is run by a team that includes Jensen, Joe Schalk – who has 47 years of chamber experience – and Steve Martin, both Air Force attitude chamber training veterans. Additionally, Janelle Johnson, a finance associate for the UND Aerospace Foundation, works part-time with the altitude chamber crew.

During his time at UND, Fluke also worked recruiting events and in other capacities for Ken Polovitz, UND Aerospace assistant dean, Kim Higgs, academic advisor, and Amy Sand, academic advisor, all with the John D. Odegard School of Aerospace Sciences.

"They were like parents and advisors," Fluke said. "It was fun to work for Aerospace in all different aspects including student services and flight instruction. We went on recruitment trips, talked to hundreds of students, attended the Oshkosh Air Show, and worked to interest people in the program. I still keep in touch with many of those students today."

But among his most valued experiences at UND, Fluke notes, was those critical minutes of instruction with a flight surgeon and crew in a big steel box in Odegard Hall.

"I called 'Doc' a couple of days after the decompression incident in the CRJ and thanked him," Fluke said. "The first signal I felt in that airplane was what I'd felt in Dr. Jensen's class."

Juan Pedraza

University Relations writer

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