Biz Wave: John R. Clarke & Middle Waters

John Clarke
Photo property of John Clarke.

What are some of your primary responsibilities as the Director at the United States Navy Experimental Diving Unit?

I have been the NEDU Scientific Director since 1991. As such, I am responsible for the scientific rigor and validity of all of our scientific and engineering products.

I lead a team that reviews the scientific methods and appropriateness of all of NEDU’s human research. I develop new equipment testing methods and am responsible for publishing unmanned testing manuals, including the 1994 NEDU Unmanned Test Manual and the 2015 update to that manual. I have also carried those test procedures forward into NATO documents for breathing apparatus tests and sodalime quality control testing.

I am dual-hatted as the Department Head for Unmanned Test and Evaluation, and as such have led the testing of not only diving equipment, but also life support systems for fighter aircraft, military gas masks, and miners’ emergency rescue equipment. I am also responsible for the Navy’s diving accident investigations.

You’ve traveled quite a bit through your work in the Navy and Smithsonian Institution. What are some of the highlights of your work and travel?

Virtually all of my travel has been work related. Highlights have been diving the Red Sea, Caesarea, the Great Barrier Reef, and work in both Polar Regions. Antarctica was the most unique work location by far.
Lately I have enjoyed helping produce a new generation of diving scientists and engineers through Ph.D. programs in Ireland and Sweden.

Many recognize you for your research on underwater breathing apparatus. Have you worked more with SSA or SCUBA?

We work with it all; surface supplied air, nitrox and heliox.

We recently tested the KM 97 stainless steel diving helmet in air and heliox mode. A lot of our work is with military rebreathers: oxygen sets, semiclosed mechanical rebreathers and fully-closed electronic rebreathers. We test systems for bounce and decompression diving, and saturation diving. Cold water scuba has been a major research emphasis for the past ten years.

My colleagues develop new decompression procedures and procedures for maximizing mission efficiency while minimizing oxygen toxicity, and for optimizing work performance in diving. My more challenging personal contributions have been in modeling the chemical kinetics of rebreather scrubber canisters, and real-time modeling of semiclosed rebreathers.

John Clarke Shackleton
John standing next to explorer Ernest Shackleton’s hut. Photo property of John Clarke.

Nowadays, do you work more with divers, or engineers and scientists?

As Head of the Test and Evaluation Department, I work personally on a daily basis with Navy and civilian divers, and with engineers (who are also divers). Each Navy diver in my department is elite and highly experienced; they receive one-on-one attention.

As Scientific Director, I work daily with our military physicians, all of whom are Navy qualified divers. I also work several times a week with our civilian scientists. Four of our civilian diving researchers are highly experienced deep diving cave divers, recreationally using scuba and rebreathers with nitrox and trimix. Some of them direct or aid our diving accident investigations.

You’re also a pilot. When did that interest spring up in your life?

Both my brothers were pilots; my oldest brother was an F4U fighter pilot, and later a helo pilot; he was my hero growing up. My next older brother took me flying before he even had his pilot’s license.
My high school graduation gift in 1964 was flying lessons. I got my Private Pilot’s license in 1974, and my Instrument Rating in 1978. I’ve owned two airplanes: a Cessna 150 and a Piper Arrow. I’ve flown Cessna 172’s at Tyndall Air Force Base; hence the story about flying into Tyndall AFB in “Middle Waters”.

My flying at Tyndall AFB was also mentioned in the underwater thriller The Moon Pool written by my friend Max McCoy.

How has your maritime experiences helped you create a more realistic world in your book, “Middle Waters”?

I’ve been diving since 1964, was a graduate of the Navy’s Scientist in the Sea program, was taught by the father of saturation diving (Dr. George Bond) and dived on NOAA’s Aquarius habitat.
I went through Navy Dive School at the Washington Navy Yard in 1980. I’ve dived around the world and conducted deep-sea shipboard and laboratory research with animals and humans at pressures of 5000 psi (animal research) and 1500 feet sea water (human research). I’ve conducted scuba research in Antarctica.

Basically, if I hadn’t had the unique maritime experiences I’ve had, the novel “Middle Waters” would not have been possible.

Middle Waters
Artwork property of John Clarke.

Aliens, deep-sea, military. How did you combine all of these interesting elements into one storyline for your book?

First of all, underwater ET’s are a “foil” for the protagonist Jason Parker and his star-child student turned accomplice, Laura Smith. A foil is a fictional device used to test and refine the character of the protagonist. And that device, and the girl, had a profound effect on the Navy diving researcher, Jason. Since ET’s are simply a device used in writing, they are not to be taken too seriously. I’ve never seen one, and I doubt I ever will — fiction is called fiction for a reason.

That said, the nuclear physicist Enrico Fermi once famously asked, regarding ET’s, “Where are they?”

Well, the deep-sea may be able to provide that answer. Military and commercial divers know that oxygen is toxic: if we get too much of it we damage our lungs or suffer convulsions. If an ET species evolved on their home world in a low oxygen environment, our oxygen-rich atmosphere would be toxic to them. So those oxygen-intolerant ET’s would not appear on land, on Earth. But underwater? — Well, you’ll have to read the novel to find out.

How about space craft entering the water? Wouldn’t the G-loads from impact kill ET’s? Supercavitation of a properly shaped vehicle would greatly slow deceleration. In theory, even humans should survive water-entry quite nicely.

Could deep underwater habitats prove to be of military and commercial interest, especially in the Gulf of Mexico? The novel explains that.

Could a deep habitat be supported by SCUBA? No. Open circuit would waste too much gas — you’d need rebreathers. So the novel makes use of rebreathers.

Would a deep habitat make a good prison for terrorists? If you’re a saturation diver, you know the answer to that. You try to make a sudden escape from saturation, and you die a gruesome death.

The story line of “Middle Waters” may sometimes seem as confusing to the reader as it is to the protagonist. That is intentional; he is a methodical, rational man who during the course of his challenging and unusual work-a-day life encounters circumstances beyond his understanding and control. Any diver would act the same way; confusion is the essence of the mystery of the UFO/ET phenomenon. But if the reader hangs on for the ride, the story comes together with a surprising and satisfying ending.


John R. Clarke serves as the United States (NEDU) Scientific Director. He is an experienced professional diver, author of “Middle Waters” and private pilot. He’s also actively involved in marine societies and research journals including the Annals of Biomedical Engineering and Undersea and Hyperbaric Medical Society.