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By Michael Menduno
Header photo by Barry McGill
The advent of mixed gas usage by sport divers—the so-called “Technical Diving Revolution”—in the early to mid-1990s greatly expanded our community’s underwater envelope, while arguably improving diving safety.
In order to appreciate how far, err deep, we have collectively come, I thought it would be illustrative to contrast the deepest tech shipwreck dives today from those in the 1990s when technical diving was just getting started.
Back in the early to mid-90s, technical diving pioneer Capt. Billy Deans, owner of Key West Diver observed that mix technology enabled us to “double our underwater playground.” Deans was contrasting the then existing recreational diving limits i.e. No stop dives to 130 ft/40 m to the new technical diving envelope that was made possible with the use of helium-based bottom gas and accelerated decompression using nitrox and oxygen. Note that during this period, the words Deep (beyond 40 m) and Decompression i.e. “The D-words,” were considered four-letter words by many in the recreational diving establishment.
At the time, we considered open water decompression dives with 15-25 min of bottom time to depths of 260 ft/79 m to represent a reasonably safe envelope for mixed gas tech dives, hence Dean’s comment about doubling of our recreational playground. Because of the ability to more easily stage bailout and decompression gas in the cave environment, the envelope there was considered deeper/longer. That is not to say that tekkies weren’t diving deeper than 260 ft/79 m and staying longer, but at that time, we considered these dives as “exceptional,” requiring special methods and work.
Deep Shipwreck Dives in The 1990s
The first table (below) highlights the ten deepest tech wreck dives from 1989-1999, including the location, depth, dive profile, technology used and the technical divers who first dived the wreck in question. The majority of these dives was reported at the time in my magazine aquaCORPS Journal.
The deepest tech shipwreck dive at the time was on the Edmund Fitzgerald lying in 530 feet (162 meters) of fresh water in Lake Superior the equivalent of 514 ft/157 m of sea water. The shallowest was the RMS Lusitania near Kinsale, Ireland at 310 ft/95 msw.
Note that the depths listed in both tables should be considered as relative metrics. In most cases, the depth indicates the depth at the bottom of the wreck. In some cases, divers actually dived to the bottom. In other cases, the depth indicates the depth that divers actually reached. In other words, the depth numbers are a bit fuzzy.
There are several observations to be made. First, all of these dives but one, were conducted on open circuit scuba. At the time literally, only a handful of technical divers had rebreathers, which were either modified Carleton Mk 15.5s, Dr. Bill Stone’s handmade Cis-Lunar rebreathers, the Halcyon PVR-BASC semi-closed rebreather aka “The Fridge,” the predecessor of the RB80, or various prototypes. AP Diving’s Inspiration, the first production rebreather, wouldn’t be released until 1997. In the case of the RMS Niagara (392 ft/120 m), Tim Cashman and Dave Apperly were using rebreathers made by Apperly. Though mixed gas technology was a necessary precursor, rebreather usage would not hit its stride for another decade.
Two of the dives shown on the chart, the SMS Frankfurt (420 f/129 m) dived in 1994, and the Ostfriesland (380 f/117 m) dived in 1990, were conducted by wreck diving pioneers Ken Clayton and Gary Gentile on heliox. Clayton also dived an experimental Neox mix (02 and Ne) for their last dive on Ostfriesland to 340 f/104 m with 20 min BT.
In 1989, the Clayton, Gentile and their team also conducted a deep air dive, with air decompression—can you imagine??—on the USS Washington (290 ft/89 m), which would have been #11 in the 1990s table. Ironically, though cave divers quickly embraced “special mix” technology, the majority of dedicated U.S. Northeast wreck divers were slow to adopt mix technology to replace their deep air diving though they did add oxygen and or nitrox for decompression.
In terms of divers, Terrence Tysall, now the training director for National Association of Underwater Instructors (NAUI), made the two deepest dives on the list in 1995, first on the Fitzgerald in 1995 with Mike “Zee” Zlatopolsky, and then on the Atlanta with Aussie pioneer Kevin Denlay.
Though the rumor was that Tysall and Zee had made a “sneak dive” on the Fitzgerald which was a grave site, the two were able to obtain a permit, but it did not allow them to tie into the wreck. They ended up using the drop camera umbilical as a downline, and left a plaque on the “Fitz” to commemorate the sailors that had been lost. However, they were only able to make a single dive due to the weather.
Clayton, Gentile and their teammates accounted for three of the ten deepest wrecks while Gentile was involved with four of 10, and Deans and his team accounted for two dives on the list. Note also that British tekkie Polly Tapson, one of the first female tech expedition leaders, and her team Starfish Enterprise captured the imagination of the community at the time with the preparations and their successful dives on the “Lucy” in 1994.
Three years later, British tech pioneer and inventor Kevin Gurr launched the first technical expedition on the Britannic with Dave Thompson, founder of JJ CCR, Al Wright, Global Underwater Explorers’ (GUE) Richard Lundgren, his brother, photographer Ingmar Lundgren, photographer Dan Burton, and British tekkie John Thornton. Of course, the wreck was first discovered and dived by Jacques Cousteau and his team in 1976, see footnote.
In terms of depth, the average depth of these 1990s wrecks is 389 ft/122 m average bottom time: 16.7 min, and average run time: 192 min or just more than three hours.
The Deepest Shipwreck Dives Today
The second table shows the 30 deepest technical shipwreck dives as of this year identifying the first tech teams to dive on the wrecks. Note that only the eight deepest shipwreck dives from the 1990s made it on the list. The deepest tech shipwreck dive, was on the Milano lying at a depth of 774 fresh water (236 mfw) in Lake Maggiore, Italy, (the equivalent of 751 fsw/176 msw), conducted by Pim van der Horst, Mario Marconi, and Alessandro Scuotto in 2008, with the help of diving pioneer Nuno Gomes who was a consultant and witnessed the dive.
The 30th deepest wreck dive is now the SMS Ostfriesland (380 ft/116 m), which was just slightly shallower than the average depth of the Ten Deepest Shipwrecks from 1990. The deepest wreck dive in the 1990s, that being the SS Edmund Fitzgerald, aka ‘The Fitz,” laying at 529 ffw/162 mfw, is now #11 when viewed from today. That is to say that the top ten deepest shipwreck dives were all conducted after 2000.
Note also there is one high altitude shipwreck dive on the list being the SS Tahoe at 471 feet of fresh water/144 m, the equivalent of 457 ft/140 m of seawater, which lies in Lake Tahoe at an altitude of 6224 ft/1897m. The altitude makes the SS Tahoe a no-man’s land in terms of decompression knowledge; there is almost no data to validate procedures for aggressive dives at that altitude. Only Sheck Exley and Nuno Gomes’ series of sub-500ffw/153mfw open-circuit cave dives in 1992-1996 at Boesmansgat sinkhole that lies at an altitude of 5000 ft/1500m in South Africa were possibly more extreme.
Also interesting, 9 of the 13 wreck dives in the deepest 10 today (there were multiple shipwrecks at the same depth) were conducted on rebreathers vs. four on open-circuit scuba. All but one of the 10 deepest shipwreck dives in the 90s were conducted on open circuit. All the 30 deepest dives but two, were made using trimix as a back gas or diluent, the exception was the Frankfurt and Ostfriesland first dived by Clayton and Gentile and team as noted above.
Closed-circuit technology is largely responsible for the deeper depths and longer dives we see today. The average depth of the ten deepest shipwreck dives listed in chart two is 576 ft/176m, or 178 ft/75 m deeper than the ten deepest shipwreck dives from the 1990s. Average bottom time for the deepest 10 today was 15 minutes compared to 16.7 min for the 1990s wrecks, however average run time was 316 minutes or more than five hours, compared to a little over three hours in the 1990s.
The amazingly prolific Italian diver Massimo Domenico Bondone and his team accounted for six of the dives in the 20 of the 30 deepest shipwrecks! Wow! He is followed by Irish tekkie and photographer Barry McGill, his colleague Stewie Andrews, and their various teams who were responsible for four of the deepest dives shown on the table. Aussie tekkies Dave Bardi, Craig Challen, Richard “Harry” Harris and their colleagues from the “Wet Mules,” who were prominent in the Thai cave rescue earlier this year, were responsible for three of the dives as were Ken Clayton and Gary Gentile (from the 1990s). Tysall
Was responsible for two dives on the list, the Fitzgerald and the Atlanta.
Have we bottomed out our depth capability as self-contained divers? If history is any judge likely not. My long-held belief is that self-contained atmospheric diving systems aka Exosuits or hard suits, such as those pioneered by commercial pioneer Phil Nuytten, founder and CEO of Nuytco Research, represent the next wave of technology that promises to extend our envelope even further. However, given the slow pace at which diving technology evolves (it’s a matter of economics), it may be a while before divers will have access to $10,000 swimmable Exosuit.
Even so, it will be interesting to see what the list of the 10 deepest tech shipwrecks dives will look like in 2029.
Editor’s Note: This post evolved based on input from our readers. Here were the two earlier versions:
A printed version of this article was published in the “Journal of Diving History, Third Quarter 2019, Vol 27 Number 100.
Table 1: 1990s
Deepest 10 (1989-1999): Average depth: 398 fsw/122 msw, Avg Bottom Time: 16.7 min Average Run Time: 192 min
*Note that Tysall & Zee’s dive on the Fitz was not a “sneak” dive. The two obtained permits to dive the wreck but they didn’t allow the divers to tie in.
** Denlay & Tysall’s first dive in 1995 was to 361 fsw/110msw on the shallow stern of the Atlanta. They returned in 1997/98 where they made their deepest dive to the bow.
** Jacque Cousteau, Albert Falco (team leader), Raymond Coll (camera), Ivan Giacoletto (lights) and Robert Pollio (photo), were the first to dive the Britannic in 1976. Their first recon dive was on air!! Subsequent dives with BT: 15 min were made with Trimix 14/54. The team deco’d in a bell. GUE launched its own expedition in 1999 which included the Lundgren brothers.
Table 2: 30th Deepest
Deepest 10 (1990-2018): Average depth: 576 fsw/1176 msw, Avg. Bottom Time: 15min, Avg. Run Time: 374 min
*The Jolanda sits vertically from 70-150 msw. According to M. Ellyat, Gregory ‘Banan’ Dominik found and dived the deep bit of the Yolanda in Sharm 3 years before Mark Andrews and Leigh Cunningham.
** According to M. Ellyat When he found the Victoria in 2004 it was almost intact in 156m. Subsequent dynamite fishing has blown the inner decking down to the seabed making it appear 144m.
***Rizia Ortolani set the then Deep Wreck Female record on this dive.
**** Scuttled in Operation Daylight, Operation Deadlight Type VII.
*****Denlay & Tysall’s first dive in 1995 was to 361 fsw/110msw on the shallow stern of the Atlanta. They returned in 1997/98 where they made their deepest dive to the bow.
****** The wreck had been dived previously in September 2000 by Richie Stevenson, Chris Hutchison and Dave Greig but only as a bounce w/ 2 min bottom time. Subsequent dives with BT: 15 min were made with Trimix 14/54. The team deco’d in a bell. Greek commercial diver Kostas Thoctarides followed Cousteau in 1995 making a solo 20-min dive, and returned in 2001 with a submersible.
********Clayton dived Neox mix (O2 and Ne) for their last dive on Ostfriesland to 340 f/104 m with 20 min BT.
Michael Menduno is InDepth’s executive editor and, an award-winning reporter and technologist who has written about diving and diving technology for 30 years. He coined the term “technical diving.” His magazine “aquaCORPS: The Journal for Technical Diving”(1990-1996), helped usher tech diving into mainstream sports diving. He also produced the first Tek, EUROTek, and ASIATek conferences, and organized Rebreather Forums 1.0 and 2.0. Michael received the OZTEKMedia Excellence Award in 2011, the EUROTek Lifetime Achievement Award in 2012 and the TEKDive USA Media Award in 2018.
Isverna Cave, Diving An Underground Dacia
Italian explorer and tech instructor, Andrea Murdock Alpini, waxes poetic about his first exploration dive in Isverna Cave, located deep in the Earth beneath the wilds of Romania.
by Andrea Murdock Alpini
Film and Photos by Andrea Murdock Alpini
Early in January 2020, feeling fortunate to dive the stunning Isverna Cave located in the Balkans, Andrea Murdock recorded his impressions in a diary as it is shown here.
ISVERNA CAVE, The Trip
Footprints, steps and transfers
A small team of divers, Stefano Beatrizzotti, Nathan Zot, and Luca Bricalli from Switzerland, and I, the fourth diver and also the writer and filmmaker, are ready. We’re going to dive into this stunning cave with three siphons: Green Syphon, a narrow passage with a strong current; a breath-taking dry passage to the Yellow Syphon; and finally the Black Syphon, which is more than 400 m/1312 ft long and 42 m/140 ft deep—the longest flooded siphon in Romania. The permissions have been granted, and we have a goal to accomplish: an amazing adventure among these ancient rocks.
Isverna Cave is located at around 600 m/1959 ft elevation, in the Oltenia region, bordered on the north by Transylvania, made famous by the legend of Count Dracula. The first recorded exploration took place at the beginning of WWI, in 1914, and it has been studied and thoroughly written about over the years by many intrepid pioneer speleologists, with each century contributing additional vital information. Even Jacques Yves Cousteau brought his contribution to the exploration of Isverna Cave in 1990. In 2005, the scuba speleologists Gabor Mogyorosy and Mihai Baciu found a way to the end of Black Siphon. Reaching the back gate of Black Siphon means we will have explored more than 1800 m/6000 ft of cave. However, never fear, there are hundreds of virgin tunnels that await intrepid adventurers.
Isverna Cave: Day I
We arrived in Isverna around noon local time. We had driven more than 1650 km/1000 mi in one day to reach our destination–the wilderness in Romania. In spite of our late arrival, a very calm guy welcomed us. He spoke only Romanian. Very few words, along with hand signals were used to show us to the rural “house” where we were to sleep and remain dry during our stay. Our humble abode had but a single light bulb to illuminate it, and the ‘heat’ was a fire that we took turns attending to before we jumped back into our sleeping bags for warmth.
Isverna Cave: Day II
Early in the morning, while the others still slept, I had walked to the river. I approached the cave by the external side, a semi-vertical wall of 3m/10 ft close to its entrance. A crystal-clear tiny river flowed below the main rock wall. Mosses and lichens covered the whole surface of the rock and made it very slippery. On top of it was a locked iron gateway that guarded the access. The local authority had given the key to our speleologist: Mihail Besesek.
When we were all gathered, we saw a rope at the right of the entrance to the cave. I carried my heavy bag on my back with some of my diving gear. I let go of my mass on the heels of my boots, but “not enough” Luca Bricalli said. He is an expert alpinist, and his recommendations are very useful. I lifted up the front light worn on my helmet to light up the narrow passages of the dry part of the cave. We had to walk about 220 m/720 ft before we reached the inner lake. It was incredible how the concept of slippery, narrow, safe, and precarious changed with each step. The more we moved forward, the more the morphology of the cave changed. Now and then we had to proceed on our hands and knees, skipping flooded spots around 1 m/3 ft deep. A rapid river flowing along our journey reminded us as to how difficult the dive would be.
The march moved on quite simply according to our enthusiasm but the more I walked, the more I slowed down. Sometimes I got lost in the beauty of the cave’s rooftop: indented and smooth simultaneously. Phreatic rocks made me feel wrapped in the Earth.
The airy and aquatic human feeling that we usually experience living on the surface of the Earth disappeared. Only hardness, and the fickle ruggedness of the underground remained. The rock with its achromatism seduces the person who looks at it with simple eyes.
Thirty minutes into our journey, we came to a section of the river that needed to be forded, causing us to lose time. Mostly, however, we struggled with the climb, as handholds and footholds were not easy to see.
When we were 200 m/656 ft from the entrance, we came to a lake that required us to use our small rubber boat to cross. I couldn’t avoid thinking about the Italian poet, Dante Alighieri, who wrote of an angel helmsman to whom souls sing as they are being sailed to Purgatory.
We moved the bags, cylinders, twinsets, camera, lights, drysuits and much more scuba gear to the opposite side of the lake. The operation took more than twenty minutes. A smooth, slippery, sliding rock, 30 m/100 ft, was our base camp inside Isverna Cave.
The lake was transparent, calm, and flat, as opposed to the rowdy river. On top of the slide we saw the entrance of the beloved Green Siphon for the first time.
In the cave, our voices quieted down, and the power of silence rose up. Each of us had a light on our heads in order to see where we were putting our hands. I had brought all my video gear and deco stages to the beginning of the siphon. For me, to stand up with the steel twinset 15+15 filled to 260 bar/2800psi, was extremely difficult. In fact, I needed to roll over onto my side and use my knees to stand up. I knew the rule: don’t bring it if it’s not necessary, and I broke it. My back didn’t appreciate my flagrant disregard for rules, but my soul did.
Everyone had defined his square meter as a living area. “Wearing the Inside-out” by Pink Floyd could have been a perfect song for the moment. I had prepared all my gear except for the camera and lights, which were mounted and were heavy and bulky for the large branches. I had needed more time to get ready to dive.
On this day I dived the three siphons with video equipment, which was a challenge. Sometimes I was in great pain; the flow was strong, and finning, breathing, and filming were tough. The worst moments were at the end of each siphon, when gravity forced me to feel all the weight. I was able to capture stunning dry passages in between the flooded parts, amazing views, powerful colors, and exquisite concretions.
At the end of the first day of diving in Isverna I knew I could not have given up the video equipment. I remember a moment, at the end of the first siphon, I was gripping my camera with my right hand and holding a floating rope with my left hand to help to get out of the flow. Once I was out, a narrow tunnel had to be navigated. On the left wall there was a black/brown rock with a skinny rope to hold, and on the other side, and under my feet there was a river with a strong current. I moved forward slowly with my video camera and the heavy weight of my twin set on my back muscles aching and breathing with difficulty, but blissfully happy.
The beauty of rock
The first siphon runs for more than a hundred meters. It descends quite rapidly to 15 m/50 ft deep, where a fault cracks the bottom, a nice spot for filming. While I was finning, I used my free hand, the one not gripping the camera, to dust the floor of the cave. A layer of sand covered the spare parts of some enchanting chromatism by the rocks. This simple operation meant waiting before the silt settled and the powerful saturated colors of the stones were bright again.
The dive profile of this segment of siphon is a yo-yo: fast descent, flat bottom, and then sudden ascent to follow the form of Isverna Cave’s tunnel. By the way, this first part of the dive had gone faster than we expected. I decided I wanted to come back the next day to pay better attention to the surrounding areas that were on the main line.
When I was back at the surface, I was touched by the color of the rocks I saw in front of me. The dome is apparently wide. A small colony of protected bats live here. They are not the heirs of Dracula, of course, but their presence here gives a magical feeling of being there. I barely shined my lights, and the bats beat their wings and flew away, back into the darkness. While I watched the bats, the surface flow pushed me in the wrong direction.
I was finning strongly enough to keep my trim and keep filming. My wrists felt pain on the grip, the lights had been too large and heavy, so I had taped a lot of floating foam on the video camera equipment to lighten it and make it neutral underwater. Then and now I feel like I had a sail in front of me that slowed down my finning. It seemed that the wind slowed me down and made me lose momentum.
Walking the dry tunnel while wearing the full equipment required strong fortitude and determination. Sometimes the water rose suddenly from my ankles to my shoulders. When it covered my mouth, I breathed with my regulator and hopped on my toes. “You must be a dancer,” I repeated in my mind for those long moments, but I felt clumsy as a rookie at a dance academy school on the first day of lessons. Then, when I came out of the water, I felt like an elephant entering a fine luxury crystal store in Venice. The parasitic twin set I wore on my shoulders reminded me we were in this together, every step of the way.
Finally, we crossed the second siphon, the Yellow one, too short to forget the complexity of the recent past. A new long, dry path awaited us. In the end, when my eyes broke the surface, a masterpiece of nature was painted and sculptured in front of me.
The flow pushed and increased step by step, one moment it was in front of us, the next moment it was at our backs, sucking us down. This dry tunnel is the longest of the caves. You need to be determined if you want to dive the Black Siphon. I walked, hanging my head down, due to my shortness of breath, I have to admit it. Standing in front of the gateway to the Black Siphon was a stunning shallow lake.
A long-flooded tunnel began here, the longest of Romania, more than 400 m/1312 ft. The cave was soft, and the color of the stone was pure black to deep brown. The rocks had the power to absorb the brightness of the diver’s lights. The shape of the tunnel, bottom, walls, and roof change often. Here, nature created a real masterpiece; no artist from the past ever duplicated it.
There’s not a diver in the world who would not be fascinated by the beauty of this particular rock.
The Black Siphon has a section and a profile that shifts quickly; in a few meters, we moved from -7m depth to -42m depth (23 ft-138 ft).Today we spent no more than 40 minutes inside the Black segment of the cave, and it is our goal to return for the next days of the expedition. Finally, it was time to put our fins in the opposite direction. We had a long, arduous journey to get back to the entrance of the cave. All the team members made an “L” sign, which meant time was up. The first day of diving inside the cave was coming to an end.
The second and third siphons had been specular, as well as the dry passages that merged with them.
We had spent more than five hours inside the cave. Not bad as a welcoming dive. When we came out the sun was down, and a pale glaze in the background painted the boundary of the mountains. I was exhausted but pleased about the team’s progress on this first day, and while my face was not smiling, inside I was proud and pleased.
That night while the team slept, I could not. So, I wrote about my memories and kept an eye on the fire, for the heat from the fire warmed not only our bodies but our dry suits as well. Our rural house seemed more like a campsite, and that was all we wished for. For us to be able to share the experience we had today is a gift that none of us will ever forget.
Andrea Murdock Alpini is a TDI and CMAS technical trimix and advanced wreck-overhead instructor based in North Italy. He is fascinated by deep wrecks, historical research, decompression studies, caves, filming and writings. He holds a Masters 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. Recently he published his first book entitled, Deep Blue: storie di relitti e luoghi insoliti.?
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