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U-1105: The Black Panther, The World’s Most Accessible U-Boat

Explorer and maritime historian Erik Petkovic details the development, history and eventual demise of Germany’s U-1105, which represented the cutting edge of the arm’s race between subsea hunters and the hunted during WWII. Resting in the brackish waters of the Potomac River near Piney Point, Maryland, USA, the U-1105 is the most accessible sunken U-boat along the US East Coast.



by Erik Petkovic

All photos by Erik Petkovic unless otherwise noted.

U-1105 was a highly modified Type VIIC nicknamed the Black Panther.

In the infancy of 1942, the American shoreline was ablaze and its waters ran red with blood and black with oil. Operation Paukenschlag (Drumbeat) had just commenced. The mastermind of Paukenschlag, Admiral Karl Donitz, authorized five Type VII U-boats to unleash hell in American waters. 

Reinhard Hardegen, commander of U-123, and his fifty-one man crew were in one of the U-boats assigned to Paukenschlag. Although unknown at the time, the world would know who he was in short order as he took aim at a tanker from 4 km/4,400 yards. U-123 hit the tanker with multiple torpedoes and sank Norness off New York. When Americans awoke to the headlines the next day, America would never be the same, and neither would the American psyche. This was the second time in five weeks (Pearl Harbor was attacked on December 7, 1941) and the second time since the War of 1812 that America was attacked on its home soil. 

Paukenschlag was a massive success from the Kriegsmarine perspective. From the Allied perspective, it was massively destructive. Paukenschlag was just the initial onslaught. The drum continued to beat long after Donitz’ five U-boats returned home. In the first seven months of 1942, 109 ships were lost in American waters along with 2,081 mariners. 

To combat the significant loss of life and vessel, the Allies—through ingenuity and engineering—developed three keys to turning the Battle of the Atlantic. The first was High Frequency Direction Finder aka “Huff-Duff”. Although this technology was not new (as the ability to locate low frequency bearings had been used for years) the British were able to tune the technology to be able to take bearings on high frequencies when U-boats surfaced to transmit weather reports or to coordinate wolf pack attacks. 

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The second advancement—breaking the secret code of the German Enigma machine—was arguably the most significant. The painstaking work by Alan Turing and those at Bletchley Park not only turned the tide of the Battle of the Atlantic, but of World War Two.

The further development of ASDIC, named after the Anti-Submarine Detection Investigation Committee, proved an effective weapon against the Grey Wolves. Known as SONAR to the Americans, ASDIC evolution was war-changing. The hunters became the hunted. 

These advancements were so effective that while 109 ships were lost in American waters in the first half of 1942, zero vessels were lost in the second half of the year. As a result, U-boats were being obliterated at an alarming pace. The horrific U-boat losses caused a change in tactics: Donitz recalled the U-boats from the western Atlantic, the Kriegsmarine shifted back to lone wolf operations from wolf pack attacks, and the Allied advancements necessitated new U-boat design and engineering. Enter U-1105.

A view off the port bow of U-1105 in dry dock. Alberich tiles can be seen attached to the hull.


When U-1105 was launched on April 20, 1944, (Hitler’s 55th birthday) World War Two was a year from being over. The “Happy Times” had long since disappeared. The wolves were being slaughtered in high numbers. By the end of the war, the casualty rate for Kriegsmarine submariners was nearly 75%—upwards of 28,000 sailors and nearly 800 U-boats would be lost. 

The Germans built seven varieties of Type VII U-boats. Of the 709 Type VII U-boats completed, 577 were Type VIIC, including U-1105. However, U-1105 was not a typical Type VIIC. U-1105 was a highly modified Type VIIC with the latest in German engineering.


The Kriegsmarine attempted to counter the effect SONAR was having on their disappearing U-boat fleet. The Germans developed a synthetic rubber material which absorbed and dispersed sound waves—in effect, they engineered an acoustic camouflage dubbed Alberich.

An early form of stealth technology, Alberich tiles were engineered with different patterns of holes perforating the rubber which allowed the rubber to absorb the sound pinging them by SONAR from Allied ships. Similar to the tiles on the space shuttle decades in the future in which tiles were specifically engineered for a certain part of the space shuttle, specific hole patterns were engineered for specific parts of the U-boat.

Studies showed Alberich could reduce the likelihood of detection by up to sixty percent. Despite the technological and engineering innovation further enhanced by successful trials, only thirteen U-boats were outfitted with Alberich. U-1105 was one of only four U-boats outfitted with Alberich that went on a war patrol. 

A tile of Alberich from U-1105’s conning tower. Each tile contained a unique set of holes to absorb sound waves – an early form of stealth technology.
A sheet of Alberich can be seen peeling away from U-1105’s hull.

GHG Balkon

Early U-boats were outfitted with a passive sonar array called Gruppenhorchgeraete (GHG). The GHG was placed just aft of the torpedo tubes on either side of the bow containing a dozen hydrophones which helped the U-boat listen to underwater sounds and decipher Allied propellers.

Limitations with GHG lead to the development of the GHG Balkon—an advanced listening system with 48 hydrophones. The GHG Balkon increased the effective range of the U-boat’s listening capability by an astounding 70 percent. The system was so effective sounds could be heard over the horizon. U-1105 was one of nearly two dozen U-boats to be equipped with GHG Balkon. 

The GHG Balkon – an active sonar array containing 48 hydrophones – was a significant upgrade which allowed U-Boats to hear sounds over the horizon. The GHG was so effective it was immediately copied by the Allies and placed on submarines.


U-boats had two ways of operating – either by electric, battery powered motors or by diesel engines. U-boats could not use the diesel engines while submerged; otherwise, the engines would suck all the air in the U-boat into the engines and the crew would suffocate.. Installation of a schnorkel allowed the U-boat to operate submerged while using the diesels.

The introduction of the schnorkel was more successful than any navy would have imagined. At the beginning of the war, U-boats could stay submerged for three days. By the end of the war, schnorkel technology had been perfected to allow a U-boat to stay submerged in excess of sixty days. This remained a record until the US Navy broke it in the 1970s, but only by use of nuclear power and after decades of Cold War engineering. 

A US Navy sailor testing a U-Boat schnorkel in the Chesapeake Bay in 1956. 

Black Panther

U-1105’s conning tower emblem depicted a black panther sprawling over the world. U-1105 commanding officer, Oberleutenant zur see Hans-Joachim Schwarz explained how U-1105 received its nickname: “The name and the heraldic figure were the result of a competition in the crew. A black panther is a beast of prey in the open country. In wartime, a U-boat is also a beast of prey that attacks ships on the surface. Because the boat was covered with a black rubber coat, we thought that the name was very suitable for U-1105.”

A starboard quarter view of U-1105’s conning tower and upper and lower wintergartens with automatic weapons prior to sea trials with the Royal Navy.


On April 12, 1945, U-1105 ventured out in the name of the Fatherland to the western approaches of Ireland—U-1105’s hunting grounds. Careful transit of the North Sea saw U-1105 arrive west of the Outer Hebrides on April23. Schwarz surfaced briefly to send a transmission to Befehlshaber der U-boote (BdU)—U-boat headquarters. The message was short and concise: “My position is AM 0213. Weak defense and patrol.” The U-boat was so close to shore the men could see advertisements, lights, and vehicles. No one knew U-1105 was there. 

U-1105 commanding officer Oberleutnant zur See Hans-Joachim Schwarz.

On April 27, 1945, HMS Conn, HMS Redmill, and HMS Rupert, members of the Royal Navy’s 21st Escort Group, were in Irish waters carrying sonobuoys to detect U-boats. U-1105 heard the noises of the three ships. At this time, HMS Conn picked up a sonar contact which was believed to be a U-boat, but was in fact an incoming torpedo from U-1105. Fifty-seconds after firing the T5, a massive explosion rocked HMS Redmill. U-1105 remained undetected.

U-1105 attempted to descend to 100 m/330 ft to escape what was believed would be an imminent and ferocious depth charge attack. The emergency descent quickly became uncontrolled with two tons of water in her ballast tanks. U-1105 hit bottom at 570 feet. U-1105 turned off its engines and sat on the bottom. Schwarz counted 299 depth charges dropped on U-1105. After 31 hours on the bottom while avoiding detection, U-1105 surfaced.

The crew of U-1105 poses on the conning tower and upper and lower wintergartens. The command staff stands on the main deck. Commander Schwarz in third from the right in the white hat. 


Six days later U-1105 received the order to cease all combat. World War Two was over. U-1105 surrendered at Lisahally. En route, U-1105 destroyed all classified material, communications, and paper, including her log book. All torpedoes in the tubes were discharged overboard. Additionally, all ammunition and seals for the submarine’s weapons were dumped overboard. Ironically, U-1105 surrendered to the 21st Escort Group – the same group U-1105 attacked and killed 32 of its men when it torpedoed HMS Redmill

A previously classified drawing showing the placement of the 250 pound MK6 depth charge suspended beneath U-1105’s hull.

Testing & Evaluation

All U-boats surrendered at Lisahally, with the exception of U-1105, were destroyed per Operation Deadlight. Intelligence personnel knew from previous prisoner interrogations that Alberich existed and that the Allied forces were keen to start testing and evaluations. U-1105 was the one prize the US, British, and Soviet forces were interested in testing. The Americans were eager to get their hands on U-1105, but would have to wait until the Royal Navy completed their own trials and testing.

In January 1946, after a harrowing trek across the angry North Atlantic, U-1105 finally arrived in the United States and was authorized for salvage and explosives testing. At the conclusion of the proposed tests, U-1105 “shall be finally disposed of by sinking in waters of such depth as to assure a swept depth of at least fifty feet.”

U-1105 at detonation in the Potomac River.

Thirteen months of testing saw U-1105 sink five times. On September 19, 1948, at 1229 hours, a 113 kg/250 pound MK2 depth charge suspended 9 m/30 ft below U-1105’s conning tower was detonated. U-1105 sank in less than one minute for the sixth and final time. 

US Navy personnel arming the MK6 depth charge.

Diving U-1105

U-1105 rests at a depth of 28m/91 ft in the brackish waters of the Potomac River off Piney Point, Maryland—the most accessible sunken U-boat along the US East Coast. U-1105’s bow points south toward the Chesapeake Bay. The wreck sits in an area with heavy commercial shipping traffic. Not only is the wreck easily accessible, but from April to November the wreck is easy to locate—a buoy marks the site.

Original drawing of U-1105 embedded in the bottom of the Potomac River by James Christley in 1991. Starboard bow orientation. Courtesy NPS. 

The buoy is marked with several advisories including: POOR VISIBILITY, STRONG CURRENTS and US NAVY PROPERTY OBJECT REMOVAL PROHIBITED.

A small diver ball is tied directly to the top of the conning tower at a depth of 20 m/65 feet. The line is usually secured around the base of either the attack periscope or sky periscope. Free descents or hot drops are not advisable on this wreck. With the limited visibility and a seemingly ever present current, one would not be guaranteed to see the wreck if a free descent was performed. It is recommended to dive the wreck based on tide tables, with the best conditions being at or near slack high tide. 

The fall and winter months allow for better visibility, less pleasure boat traffic, and fewer jellyfish. Visibility can double or triple in the winter months (2-3.5m/6-12 ft) compared to the summer months (1-1+m/3-4 ft).

The gun mounts are all that remain of U-1105’s 2cm Flak.

The Potomac quickly turns various hues of mundane color – greenish-brown, then brown, then shades of black. Regardless of color, it is murky. Vertical visibility is almost always better than horizontal visibility. As you approach the 18 m/60 ft mark in the black water, the faint outline of the top of the conning tower comes into view. The most prominent feature is the sky periscope housing and mount which projects above the conning tower.

Other features in the conning tower include original teakwood, attack periscope mount, diesel engine air intake, and housing for the FuMO Hohentwiel radar. The large 2 cm watertight ammunition container is located at the entrance to the upper Wintergarten. The Flak 38 gun mounts can be seen bolted to the original wood decking. 

The hinge and cap are still in place on the storage tube which once housed U-1105’s colors. 
U-1105’s 2cm ammunition container at the aft end of the conning tower.

The diver will continue aft along the starboard side of the upper Wintergarten and drop onto the lower Wintergarten. Immediately to the diver’s left is the external watertight storage tube. This is where U-1105’s flags were stored. Two 3.7mm watertight ammunition containers and the M42 automatic machine gun mount can be viewed.

Teak decking can still be seen on the lower Wintergarten. 
U-1105’s sky periscope mount protrudes from the conning tower.

There are some interesting features to see while dropping down along the main deck and circumnavigating the superstructure. Below the sky periscope, flaring out from the conning tower on the right (while looking aft), is the rectangular base for the schnorkel. This is where the schnorkel would clamp into the conning tower when deployed. Along the starboard side of the conning tower is the exhaust trunking. This intricate piping is a very unique piece of maritime history, as this is one of very few sunken U-boats in the world where this can be seen. 

Alberich can be seen in a multitude of places on and around the superstructure including the conning tower, both Wintergartens and saddle tanks. In 2009, the U-1105 Black Panther Historic Shipwreck Preserve was included on the inaugural list of the National Oceanic and Atmospheric Administration’s National System of Marine Protected Areas. 

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Dive Deeper

US Naval Institute: “To Hell, By Compass: The Remarkable Wreck and Rescue of USS S-5”
by Erik Petkovic

Osprey Publishing: German submarine U-1105 ‘Black Panther’ THE NAVAL ARCHAEOLOGY OF A U-BOAT

Wikipedia: German submarine U-1105

Erik Petkovic is an explorer, author, maritime historian, shipwreck researcher, and technical wreck diver. Erik is the author of multiple wreck diving and maritime history books. Erik has been featured in publications worldwide and is a consultant for various production companies. Erik regularly presents at the largest dive shows and museums and is a sought after presenter due to his unique storytelling and in-depth research. He currently lives in Southern Maryland with his wife and sons.


Hal Watts: Plan Your Dive

Known for his deep air diving exploits back in the day, 86-year-old Hal Watts, aka “Mr. Scuba,” is one of the pioneers of early scuba and credited with coining the motto, “Plan Your Dive. Dive Your Plan.” He founded the Professional Scuba Instructors Association International (PSAI) in 1962, which eventually embraced tech diving, but never relinquished its deep air “Narcosis Management” training. Italian explorer and instructor Andrea Murdock Alpini caught up with Watts and teased out a few stories from the training graybeard.




Interview by Andrea Murdock Alpini 
English text by Vincenza Croce

Hal Watts, Terrence Tysall, and Bill Stone in March of 1993.  This was the last stop in the U.S. for a test dive of the Cis-Lunar Mk-4 rebreather prior to Stone’s San Agustin expedition (1994) for its first real sump dive.

“Plan your dive, dive your plan,” is a common refrain in diving, but it’s easy to forget the meaning of this phrase has changed over time.

The underwater explorers of the early days learned to plan their dives with watches, depth gauges, and US Navy tables. Back then, decompression tables were the Bible for divers—something miraculous, halfway between alchemy and physiology. Those trail-blazing divers defined what it meant to “plan” a dive.

But, at the time, the term “technical diving” did not exist; divers breathed air on the bottom as well as during decompression. Only after many years was oxygen added, followed by the famous jump into the hyperbaric chamber.  

Later came new innovations after a few decades of experiments: hyperoxygenated binary mixtures, the NOAA tables, Heli-air (i.e. the addition of helium in tanks loaded with air), the change in the speed of ascent, new molecules to be studied, new physiological and narcotic effects, and their consequent impacts on humans and their psyches.

In a very short time, diving traditions underwent a metamorphosis. The spool and the coral tank became a proper reel, the ascent bin and the plastic bag disappeared in favor of the buoyancy control device (BCD), the surface marker buoy appeared—and then, even later on, wrists were adorned with underwater computers instead of decompression slates.

Divers later renewed and revolutionized a niche discipline, transforming it into a sporting phenomenon and a vocation. Faced with imminent change, there is often nothing that can be done when an anomalous wave arrives; you cannot stop its irresistible force with the wave of a hand. And thus was the American revolution of underwater technique, where the means of exploration—read mixed gas and scooters—have become the end.

The self-proclaimed originator of the “plan your dive, dive your plan” motto was 86-year old Hal Watts, the founder of American didactic Professional Scuba Association International (PSAI) and a diving pioneer who once held the Guinness Book of World records for deep diving. Though the use of trimix grew in popularity, Hal continued to believe in deep air, in the ancient technique of coral fishermen. He supported wreck and cave diving—with decompressive mixtures and new configurations through PSAI; but, above all, he believed (and continues to believe) that deep air, if properly practiced, is a discipline with unique logistics, hidden dangers, and irresistible charms that can take you to a parallel world.

Hal Watts speaking at aquaCORPS tek.93 Conference

First of all, Hal, what was the dive that changed your way of seeing scuba diving? I mean, a dive that was like an epiphany, a dive which changed your point of view on a technical matter?

Hal Watts: Wow, you sure are really trying to test my old man memory. Now I’ll have to review some of my old logbook entries. 

The first scuba dive that really got my attention as to just how serious and dangerous scuba diving can be was on December 2, 1962. I was diving with Bob Brown, co-owner of Florida State Skindiving School in Orlando, Florida. I was a member of a dive club in Orlando known as Orlando Sport Diving Club. Bob and I had heard of a sinkhole in Ocala known locally as Zuber Sink as well as Blue Sink. Years later, I later leased the property and renamed it as Hal Watts’s 40 Fathom Grotto, and I eventually purchased the Grotto in mid-1979.

We had never talked to anyone about the sinkhole; therefore, we had no idea about the visibility or the depth. Up to this point, I had constructed my favorite BCD, using a large white Clorox plastic jug, which we tied to our twin tank system. We put air into the BCD from our “Safe Second Stage” mouthpieces. 

Bob and I tied our safety line to a tree on the bank of the sink and reviewed our dive plan. I am reminded of the motto I came up with, many moons ago—Plan your dive, dive your plan. 

We all know that motto. I didn’t realize that it was you who coined it.

It was back in the 1960s when I was writing course manuals for NASDS [National Association of Scuba Diving Schools] and opened up my Mr. Scuba dive shop.

Mr. Scuba’s Magic Bus!

But back to the dive at Zuber. I’ve failed to mention the fact that neither of us had been doing any dives below 30 m/100 ft. We followed the cave line down slowly, not paying enough attention to our depth. Before we realized it, we had hit the bottom, stirred it up, and had no clear water.

Lucky for us, I kept the cave diving reel in my hand, and Bob kept his hand on the line. I couldn’t see; however, I could feel Bob’s hand, squeeze his fingers tight on the line, grab his thumb, and give it the “thumbs up” signal. I don’t know how we managed it, but we were both able to use our NASDS safe second stages and add air into the Clorox “BCDs.” We were actually fated to begin an uncontrolled, too-rapid ascent. All of a sudden, we hit an overhead wall, which stopped our ascent at a depth of 9 m/30 ft. 

We looked at each other, and gave the OK hand signal. While decompressing, following the old Scubapro SOS mechanical computer, I started to pull up the loose line until the dive reel appeared. Wow, we sure had an awful lot of loose line floating around us. Were we extremely lucky? Of course, we were. Our problem was that we never planned our dive, and consequently, were unable to dive a plan.

After that dive, I worked with Scuba Pro and Sportsways to create the “Octopus,” or “safe second.” A while later, the octopus appeared for the first time in Scuba Pro catalogs. I was also the first to add a pressure gauge along with the Octopus.

Hal Watts set the world deep air record to 120m/390 ft in 1967

Ah yes, the “Safe Second.” That’s what NASDS called backup second stages, right? Sheck Exley (1949-1994), the legendary cave explorer with whom you were friends, was also credited with fitting a redundant second stage reg with a necklace. I want to ask you more about Exley, but first, I want to know: What are the best wrecks you ever dived?

This is really very hard to answer. I’ll have to list four, in the order that I dived them: the USS Monitor, Andrea Doria, Japanese wrecks located in Truk Lagoon, and the Lusitania in Ireland.

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The most important would have to be the USS Monitor, a submarine used during the Civil War. A group of well-known USA divers applied to the National Oceanic and Atmospheric Administration (NOAA) for a permit to dive the Monitor, as she was located in protected waters. In addition to myself, the group consisted of: Gary Gentile, attorney Peter Hess, and several other well-known expert divers. At first, NOAA refused. Then, Peter Hess filed proper papers asking that we get the NOAA permit. To that end, we presented my Deep Air training material to the concerned NOAA group. I appeared as an expert witness and provided NOAA staff and their legal representatives with my internationally accepted training material and my record of training several world record deep air divers. Our deep air training has been accepted worldwide with zero diving deaths. After that, we received the permit. 

Other than the Monitor, my favorite deep wreck dive would be the Lusitania, which is a very personal and proud story for me. The main reason is because venture capitalist Gregg Bemis owned the diving rights to the Lucey at the time. Gregg had contacted me requesting that I train him on PSAI Narcosis Management Level V, on air—which is 73 m/240 ft—and then train him on trimix so he and I could dive to 91 m/300 ft on the Lusitania lying off the coast of Ireland. 

When word got out that I had enrolled Gregg in my Narcosis Management Course, a well-known international course director (a personal friend of mine) called and told me, “Hal, do not teach Gregg deep diving.” 

PSAI’s ad in aquaCORPS Journal circa 1994 offering deep air training.

He told me that he had been training Gregg at his facility, and that he was a “train wreck.” “He is from a very well-off family in Texas, and if you cause him any injuries, you will be sued and put out of business,” my friend said. Well, guess what? Gregg completed the 240 Level V Deep Air course, then our PSAI Trimix course. My wife, Jan Watts, Gregg, and I went to Ireland to dive the Lusitania. He and I made an awesome 91 m/300 ft trimix dive to the deck.

Diving on the Andrea Doria with Tom Mount, Peter Hess, and several great wreck divers was also an awesome dive. Last but not least was a great trip to Truk to dive on some of the Japanese wrecks.

Please tell us about Sheck.  What was your relationship with him like?

Sheck and I became friends and made several dives together, and one of my favorites happened when Sheck, his Mary Ellen, my wife Jan, and I were diving at 40 Fathoms. Sheck wanted to practice gas switches during descents. Sheck was practicing, getting ready for a planned very deep dive (I think in Mexico with Jim Bowden). The four of us swam to the east side of The Grotto, slowly following the wall during our controlled descent, watching Sheck practice gas switching. 

Sheck Exley and Hal Watts at a NSS-CDS conference

After reaching our planned depth of 73 m/240 ft, we began our controlled ascent up to our first planned deco stop. During our last deco stop on our 4.5 m/15 ft platforms, I noticed that Sheck had a funny look on his face and was messing with his drysuit between his legs. I remembered then that he had told me that he had an attachment installed in the drysuit that would allow him to pee underwater. He was clearly in a bit of discomfort and Mary Ellen, Jan and I just floated nearby and watched.

I’ve heard that Sheck later used diapers, or just cut it loose in one of his old neoprene drysuits on his big dives, so evidently he didn’t get that early p-valve to work. What about your friendship and job collaboration with Gary Taylor, your brother-in-arms and a co-owner of PSAI?

Andrea, get comfortable, since this question will take some time to properly answer.

I first met Gary in Miami, which is where we became friends when I was staying in his home and taking Tom Mount’s nitrox course.  I have a photo of Tom, Gary, and me gas blending on the floor of Tom’s garage. During the course, Tom was still using his worn-out hand written paper flip charts as his notes.

Gary was impressed with my deep air program and offered to put together an updated slideshow presentation for me to teach with. PSAI still uses an updated version of this system to date. Gary stayed with Tom until Tom thought he had sold IANTD [International Association of Nitrox and Technical Divers] to another individual. After that sale came about, Gary contacted me wanting to get more involved with PSAI. Being smarter than folks thought I was, I jumped at the chance to have Gary on the PSAI Team. Tom’s deal fell through, but Gary was totally involved with PSAI, and now is a partner and president of our agency. Thanks to Gary and Tom. 

Many, many years ago I was still taking some type of classes—I think regarding mixed gasses, maybe with Rebreathers—at Tom’s house. In fact, I was one of Tom’s instructors who did the final proofreading of one of Kevin Gurr’s manuals. Too far back to recall much about this mixed gas stuff—remember my reputation for being a deep air diver.

Tom Mount and Gary Taylor mixing up some trimix in the garage.

Speaking of the people with whom you’ve dived, was the aim of The Forty Fathom Scubapros Club?

Before I invested in a sinkhole in the Ocala, Florida, area—which was locally referred to as Blue Sink or Zuber Sink, and is now referred to as 40 Fathom Grotto—several diving buddies whom I had dived with and trained for extreme deep air diving—as well as cave exploring—got together and planned to dive The Grotto at least one Friday night per month. Within a short period of time, several other buddies joined our group, which eventually became known as The 40 Fathom Scubapro’s dive club. Each diver had to meet my requirements of training. 

Forty Fathom Grotto aka Zuber Sink
An early Sheck Exley mix course at Forty Fathom Grotto
An Eric Hutcheson drawing of Forty Fathom Grotto

Eventually, our group set specific personal requirements—being a good person, supporting our club safety rules, and making at least one 40 Fathom Grotto dive per month. We set a limit of 14 or 15 members. Three 40 Fathom members eventually set World Records for deep air: I was one, A. J. Muns, and Herb Johnson set ocean records, and later I set the air depth record for cave diving. Naturally, as time passed and we got older, our membership got smaller. It is notable that none of our club members have died during any scuba dive.

Finally, what led you to create the iconic motto, “Plan Your Dive. Dive Your Plan?” 

I used to be a private pilot, and we used to say, “Plan your flight, fly your plan.” This was back in probably 1961 when I had just started diving and there were so many instances where all the other divers would get in the water without saying anything. I’ve seen so many incidents and fatalities that could have been avoided through proper planning.

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Dive Deeper

ScubaGuru: LXD 029 : Hal Watts – Record Deep Diver & Technical Diving Pioneer

Netdoc: Netdoc chats with Mr Scuba, Hal Watts

InDEPTH: The First Helium-based Mix Dives Conducted by Pre-Tech Explorers (1967-1988) by Chris Werner

Alert Diver.Eu: Rapture of the Tech: Depth, Narcosis and Training Agencies

Professional Scuba Association International: PSAI History

Andrea Murdock Alpini is a TDI and PSAI technical trimix and advanced wreck-overhead instructor based in Italy. He is fascinated by deep wrecks, historical research, decompression studies, caves, filming, and writing. He holds a Master’s degree in Architecture and an MBA in Economics for The Arts. Andrea is also the founder of PHY Diving Equipment. His life revolves around teaching open circuit scuba diving, conducting expeditions, developing gear, and writing essays about his philosophy of wreck and cave diving. He published his first book, Deep Blue: storie di relitti e luoghi insoliti (2018) and IMMERSIONI SELVAGGE, the new one is on the way, out on fall 2022. 

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