Continued from previous post
EDU was called on in 1939 to aid in the rescue of the crew and to later salvage the
USS Squalus. She sank during a test dive on 12 May 1939 when the main air induction valve failed to close. She sank to the bottom off Portsmouth, New Hampshire in 243'/74M of water. They rescued 33 survivors of the 59 man crew. Unfortunately the rest of the crew perished soon after the sinking in flooded compartments. I remember watching this on TV with my family in the 1950s.
Four divers were awarded the
Medal of Honor for their work during the rescue and salvage. The Squalus was extensively overhauled and recommissioned as the USS Sailfish in February of 1940. She performed 12 patrols in the Pacific during World War II. I recommend
The Terrible Hours: The Greatest Submarine Rescue in History by Peter Maas for anyone interested in learning more.
World War II
The prospect of war increased EDU's focus on support for combat swimmers. The units that would become the UDT or
Underwater Demolition Team had not been formed yet.
Christian Lambertsen designed a series of pure Oxygen rebreathers starting in 1940 as a medical student. He named them Laru for
Lambertsen
Amphibious
Respiratory
Unit which became a standard for UDT and SEALs for decades.
Lambertson coined the acronym
SCUBA in 1952* to describe all
Self-Contained Underwater
Breathing Apparatus
* some accounts indicate that Lambertson used the term in the 1940s... either way, he is universally credited.
Breathing apparatus wasn't EDU's only concern. Oxygen tolerance and thermal protection were also problems that limited combat swimmers' ability to operate.
Oxygen Toxicity was generally defined in medical literature but figuring out operational limits needed a lot of work.
Dramatic improvements in aircraft technology was causing aviators to suffer closely related symptoms to divers including low PPO
2 (Partial Pressures of Oxygen), barotrauma, and DCS. Aviation pioneers didn’t always connect the dots just like the divers 30 years before. Solving these problems naturally fell on EDU. Other unusual tasks like developing an improved life jacket were assigned to EDU because of their expertise in submersion physiology.
Post-War EDU
The end of the war allowed EDU to return their primary focus to submarine rescue and diving R&D, although support for the UDT (later SEALs) and high-altitude physiology was included. Some of the notable projects included:
- Time-depth oxygen limits
- Improved air decompression tables
- Repetitive air decompression tables
- Multigas decompression theory
- Decompression treatment tables that are still the standard of care
- Diver thermal tolerance and protection
Hugh Bradner was a physicist at
UC Berkeley when he invented the wetsuit in 1952. EDU quickly began testing the new suit to understand the limits for the UDT and the evolving EOD (Explosive Ordnance Disposal) divers. Navy salvage divers weren't very interested in any form of SCUBA or the wetsuit largely because their work required communications, long bottom times, heavy-lifting support, power for cutting tools, and was usually in a relatively small area. The Mark V dominated Navy diving and was augmented by the surface-supplied
Jack Browne mask.
EDU was also a minor sponsor of
Hannes Keller and
Dr. Albert Bühlmann's revolutionary work.
Keller's dive to 1,010'/308M in 1962 smashed all human depth records. Unfortunately Keller barely survived while his dive-mate Peter Small and safety diver Chris Whittaker died.
Project Genesis
Captain George Bond started a series of "off-the-clock" experiments based on Dr. Behnke's proposition in 1942 that divers could be exposed to greater depths until tissue become fully saturated and eliminate further increases in decompression. Captain Bond began animal studies at the
Naval Medical Research Laboratory in 1957, aided by
Walter F. Mazzone. The success of animal studies led to human testing at EDU in 1962. There is a fascinating back-story of politics, dedication, and diving history described in the books
Papa Topside and
SeaLab by
SEALAB Author Ben H.. Highly recommended.
Diving pioneers including
Jacques Cousteau and
Edwin Link quickly began open-sea saturation experiments with underwater habitats. The US Navy also began their open-sea experiments with the Sealab habitats. Habitat-based saturation systems were soon replaced by surface-based chambers with diving bells (PTC or
Personnel
Transfer
Capsule in Navy parlance) outside of shallow and limited scientific projects.
The Cold War
Nuclear powered submarines and ballistic missiles convinced Navy's decision makers to reevaluate their priorities. That rapidly pushed submarine development to #1. That and loss of the submarine USS Thresher in 1963 at a depth of 8,400'/2,600M changed everything.
Government and industrial R&D funding for deep diving, manned and robot vehicles, and ocean science exploded. The fledgling offshore oil industry was also moving into deep water off California and augmented the demand. A lot of industries believed that government sponsored undersea R&D would soon rival NASA in funding.
Naval Support Activity Panama City
There were a lot of moving parts in those days, and many of involved security clearances at the highest levels and secret budgets in the billions. Some of this came to light when the book
Blind Man's Bluff The Untold Story of American Submarine Espionage was published.
EDU and the diving school had long outgrown facilities in Washington DC. NEDU (now the preferred moniker) moved to Panama City, Florida in 1975 and the school followed several years later. NEDU's new facility included the massive Ocean Simulation Facility (OSF) with an operating depth of 2,250'/690M. Five interconnected living and transfer chambers on the second deck attached to the 7,352 Ft³/210M³ horizontal wet chamber on the deck below. The entire end of the wet chamber opens for access so small submersible vehicles can be tested.
View attachment 413465
This image is courtesy of Stephen Frink from the excellent article
Deep in the Science of Diving
by Michael Menduno that was published in
Alert Diver Magazine. It gives you a sense of the wetpot's massive scale.
View attachment 414411
NEDU’s Executive Officer LCDR Steve Duba stands in the open wet pot of the Ocean Simulation Facility.
OSF's chamber temperatures can be controlled between 28-104° F/-2-40° C. Living chambers can also simulation altitudes up to 150,000'/46Km. It is still the largest hypobaric and hyperbaric research facility in the world.
The new NEDU logo reflects their R&D work for SEALs in addition to Navy divers.
View attachment 413466
I will let other Scubaboard members continue the saga because I don't have direct experience at the Panama City facility. I look forward to reading their experiences and the sea stories.
Scubaboard Footnotes
Oxygen Toxicity
Rubicon Research Repository
Deadly helmet squeeze
What do you call this gear?
Edit: Added Stephen Frink's photo and updated text.
