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by Fabio Biscotti
InD: Fabio, how often are you and your team out looking for shipwrecks?
Fabio Biscotti: Very often, due to our partnership with the U.S. Defense POW/MIA Accounting Agency (DPAA) Mediterranean Directorate, and the presence of many shipwrecks in our zone, which was the theater of some of the major battles during the two world wars.
How did you and your colleagues hear about the German sunken aircraft?
Thanks to previous expeditions of other teams that we read about in the newspaper, we decided to give our support to this history.
The planes were not very deep. What diving equipment did you use? Open circuit? Closed-circuit?
We made the dives with open circuit nitrox.
What do you plan to do with the information and photos of the Ju88A4
that you have obtained?
We are confident that we have correctly identified the pilot and the crew. We are simply happy to have been able to document this history, and we’re not going to stop. We have many wrecks to study to add to the big puzzle of human history and also to help the families of those lost. It is our pleasure.
You mentioned to me before that your group has partnered with DPAA to help screen and identify U.S. military wrecks in the South Adriatic Sea. Have you started any work with them yet?
We had our first contact with them thanks to Luigi Lacomino from Gruppo modellistico ricerche storiche Foggia (Foggia Historical Research Modeling Group), one of the best military historians in our area. He has written many books and publications about Italy’s military history. When DPAA arrived to talk with him, he immediately contacted us with the objective to create an operative squad. Our first task was to create a complete map of the aircraft crash sites around our area (Gargano-southeast Italy, Adriatic side) and take photos of the various airplanes found in the area. We have much to do and the work will be long and passionate.
I also understand that you established a Project Baseline project in Tremiti Islands National Park, Italy, in 2017. Please tell me a little about the project.
We started this project with the objective to protect our rich sea life environment by monitoring the beauties in the deep. It’s a worldwide treasure that must be preserved and protected. Our diving center organizes daily dives in fabulous places, to help people understand the kind of treasure that surrounds us.
What’s your next big project?
Actually, we are organizing some recon dives on various wrecks and plan to photograph them. We will keep in touch; I am pretty sure there will be a big surprise.
Date: March-July 2019
Location: Santa Caterina di Nardò, Italy
Objective: Recovery of WWII German aircraft/crew identity information
Depth: 36.0 m/118 ft
Wreck length: 14.40 m/47 ft
Wingspan: 20.00 m/66 ft
Height: 4.85 m/16 ft
Wing area: 54.50 m2 /178 ft2
The operational plan was based on information from previous teams that had visited the aircraft wreck site. Its location is 3.3 miles, 282 degrees WNW on a sandy bottom of 36.0 meters/118 feet.
The plane rests in flight attitude and perfectly lies on the sandy bottom broken into two sections, which was certainly caused by its impact with the sea surface. The team made a perpendicular descent on the plane, which was clearly marked by the divers who discovered this aircraft.
The remaining aft part of the plane (easily traceable tail and wheel planes) lies 15 m to SSE from the main body. Its surfaces are completely covered with incrustations due to its lengthy submergence.
As a further confirmation of the origin of the plane, there are traces of swastikas on the stern. On earlier reconnaissance, the previous team found a nameplate with engine identification numbers.
All in all, the wreck appears to be in fair condition despite having been prey to predatory acts against it. What immediately stands out at first sighting is the total lack of propellers and machine guns near the plane. The former were made of wood, which were likely damaged on impact and have likely been eaten away after being submerged for more than seven decades.
March 30, 2019:
The team of four operators conducted a survey of the wreckage and recovered a new element of study, which has been identified as an EZ6-type condenser used in German aviation during World War II.
After carefully studying the right wing, the team found that the holes discovered on the first dive were nothing but small, growing structural failures due to the salt water, demolishing the team’s original hypothesis that the plane was strafed by gunfire. Another hypothesis was based on the lack of exit holes, suggesting that the loss of the aircraft was due to other factors. After careful studies and washes on the recovered parts, we found a total absence of bursts or burns on the condensers.
The EZ6 capacitors appear, from the moment of recovery, in good condition. They are formed by a ceramic base on which the various “elements” rest. Inside the cylinders, the plastic-copper parts appear to be in good condition and, after careful attention, they are almost like new.
June 20, 2019:
Our descent was scheduled for 2 p.m., with almost no current, and we easily reached the plane. The goal of the day was to track down and identify the color of the sunken aircraft. Despite difficulties due to corrosion, we were able to study three samples at different points on the plane. The color identification confirms that it is the classic Luftwaffe green, similar to aircraft green #74 used by various services.
July 3, 2019:
We identified and confirmed traces of the yellow letter on the right side of the fuselage that previous surveys had witnessed. With the help of various historical groups engaged with us in the operation, we were able to identify the letter R, given the angle and breadth of the semicircle found. Immediately to the right a double trace was found that was most likely the letter W.
This thesis is supported by two factors. First, the characters used by the Luftwaffe on its appliances are unmistakable, and W is the only letter that displays the angles of the lines found. The second factor was the discovery by our historians of particular documentation attesting to the loss of three German aircraft in the Ionian, right in the area in front of Gallipoli where the Ju88A4, a World War II Luftwaffe twin-engined combat aircraft, rests. The documents provided a complete identification of two of the aircraft by their side tags, but we knew the third belonged to the KG54 12 Staffel (squad).
We understood immediately that the other aircraft could not be the Ju88 in question, given the fact that they belonged to different staffels where the coloring of the third character was not yellow, but another color. The only aircraft in the area belonging to the 12 Staffel was our object of study; further confirming the hypothesis was the perfect combination of the camouflage pattern found belonging to the KG54 and the yellow letter R.
Furthermore, the discovery of the letter W gives the total confirmation that it is a 12 Staffel, as this letter was used to identify this group.
We concluded that the plane in question is a Ju-88A4 under the KG54 12 Staffel. As a result, we were able to obtain the following information:
Airport base: Grottaglie Airport, Italy
Kampfgeschwader 54, Group IV, 10th/11th/12th Staffel
Ofw Brasas: He appears to have been mortally wounded. No other data is currently available.
Uffz Withalm: He was mortally wounded and subsequently died on May 5, 1942. Post-war memorialized in the Cassino Cemetery Block 15 Tomb 179. The same name is mentioned on the plaque of the Graz Cemetery with the degree of Fl.Lt. Flieger Leutnant (Second Lieutenant) and died on April 14, 1942. In both cases the date of birth coincides with the same person.
Gefr Eichhorn: He was mortally wounded and remembered in the gravestone of the lost at sea of the German army and aviation of Kiel-Laboe. Available data: Crashed in the “Mediterranean,” near Isola della Malva.
Gefr Stegmüller: He was mortally wounded and memorialized in the post-war period in the Cassino Cemetery Block 15 Tomb 109.
Mission: Unfortunately, it is not possible to know if it was a training flight or a war flight. Testimonies of the time attest to the presence of two bodies of German pilots in the trap adjacent to the crash site. Furthermore, the 12 Staffel of the KG54 was precisely in the Grottaglie area, thus further confirming this thesis.
Team members: Fabio Bisciotti (team leader), Alfonso De Filippo,Alessandro Aulicino (Poseidon Systems Italia), Rosy De Renzo, Michele Del Vecchio, Simona Pagano, Giustino Riccio, Vincenzo dell’Isola, Matteo Spada
Historical research team: Luigi Iacomino. GRUPPO MODELLISTICO RICERCHE STORICHE Foggia, Elena Zauli delle Pietre (aerei perduti Polesine), Andrea Raccagni (aerei perduti Polesine), Alessandro Zannoni
Recent law school graduate Fabio Giuseppe Bisciotti is a RAID instructor who has long been interested in natural and maritime history. Based at the Aquodiving Tremiti Diving Center in Foggia, Italy, Fabio joined Project Baseline in 2017 to help protect and monitor the underwater environment in Tremiti Islands National Park. In 2018, he partnered with the U.S. Defense POW/MIA Accounting Agency (DPAA) Mediterranean Directorate, to help screen and identify U.S. military wrecks in the South Adriatic Sea. He is currently preparing for a pilgrimage to Scapa Flow for the 100thanniversary.
Part Two: “Tech Divers, Deep Stops, and the Coming Apocalypse”
In part two of this four-part series on the history and development of GUE’s decompression protocols, GUE founder and president Jarrod Jablonski discusses the lack of appropriate mixed gas decompression tables in the early days of technical diving. He goes on to discuss the initial development of “ratio decompression” and the early thinking and rapid adoption of “deep stops,” which have come under pressure as a result of new research that questions their efficacy and safety. He also discusses the emergence of the now nearly ubiquitous gradient factors (GF) used in most dive computing. Feel free to DIVE IN and share your thoughts.
by Jarrod Jablonski
Header Photo by JP Bresser
Technical diving means different things to different people, opening legitimate arguments about different time periods and personalities involved in shaping this activity. Our purpose is more confined as I wish to focus mainly upon the development of decompression procedures. Leading figures like Jacques Cousteau (1910–1997) performed reasonably significant “technical” dives including both deep and overhead exposures. Yet, his dives were relatively short, often on air, and absent a community of fellow tech divers with whom to evolve varying strategies. Meanwhile, military or commercial activities reached significant depth with notable exposures but used different technologies and procedures. Hopefully, the following overview will be independently interesting—although I also hope to illustrate what I consider an intriguing wrinkle currently lacking in most debates over the best ascent schedule for a decompression dive.
For our purposes, I mark the 1980s as the period in which technical diving truly started to become a globally recognized activity. Of course, numerous significant projects occurred before this period, but the 1980s established a growing global awareness that amazing diving feats were possible by enthusiasts. The 1990s and the developing internet age brought these ideas progressively into the mainstream. Most importantly, these global communities could now easily communicate information and, of course, disagree about the best way to do one thing or another.
The 1980s and 1990s were also an interesting period of development because people were doing more aggressive dives but still lacked important support tools that would take another decade to materialize. For example, most early tech dives were using some form of military, commercial, or scientific tables, such as the U.S. Navy, Oceaneering International, Inc. or the National Oceanic and Atmospheric Administration (NOAA), which were often not well-suited to the dive at hand. This is because there were no decompression programs available. Divers were unable to calculate their own profiles and would trade whatever tables they could gather. In many cases, they were forced to choose from tables that were calculated at a different depth, time, and/or breathing mix to the planned dive.
Over time, the physiologist Dr. R.W. “Bill” Hamilton (1930–2011) began creating custom tables, but the lack of flexibility, as well as the cost, discouraged frequent use for most divers, especially when considering a range of depth profiles and their various time adjustments. This problem was especially prominent in deep cave diving where variable profiles and long bottom times created numerous complications . This landscape encouraged, if not demanded, that exploration divers be creative with their decompression practices. For example, Woodville Karst Plain Project (WKPP) explorers George Irvine and I began to explore ways to extrapolate from existing tables. The birth of what is now called ratio decompression originated with this practice.
By exploring the way decompression schedules develop, we began outlining simple ratios that allowed divers to adjust their decompression based upon a ratio of time spent at depth. Then, in 1998, I went on to form Global Underwater Explorers (GUE), and such practices became part of the process for helping divers appreciate the structure of decompression while supporting adjustments to profiles when depth or time varied from that expected. Regrettably, some individuals took this too far and began promoting complex adjustments and marketed them as superior to the underlying algorithms from which they had been derived.
We should leave a more in-depth review of ratio deco for another time. For now, I intend to illustrate that “rules” such as ratio deco had their roots in limited availability of decompression tables and evolved as a useful tool for understanding and estimating decompression obligation. The fact that early tech divers had limited ability to calculate profiles encouraged a “test-and-see” philosophy, further fueling the early popularity of ad hoc adjustments to decompression profiles. This was most notable in the DIR and GUE communities through ratio-style adjustments and also prominent with non-DIR advocates who used a modification known as Pyle-stops, originating from ichthyologist Richard Pyle’s early deep dives and his attempts to refine efficient ascent protocols. One common adjustment in these approaches involved a notable reduction in ascent speed, adding additional stops known as “ deep stops ”
Driven by self-discovery, the migration toward deep stops resulted in rare agreement among technical divers, and the practice developed a life of its own in conference symposiums, being advocated far and wide by a healthy share of technical divers. The earliest phases of these modifications were driven in part by limited access to decompression tables, though by the end of the 1990s there were a variety of decompression programs available. This was a big improvement, although it was still true that divers had a limited baseline of successful dives while planning mixed-gas dives in the 50 to 100 meter range and beyond. Today, most divers take for granted that technical dives planned with available resources and within today’s common use (a few hours around 90m/300 ft) are relatively safe in terms of decompression risk. When these programs first came to market, there remained many question marks about their efficacy.
The availability of decompression programs was a big advantage for technical divers, as they now had more sophisticated tools at their disposal. Yet, the output from many of these programs produced tables that were sometimes different to profiles thought to be successful by some groups. Typically, the difference related to an increase in the total decompression time and/or a distribution of stops that varied from developing consensus. These divers were keenly interested in the developing tools but reluctant to change from what appeared successful, especially when that change required additional hours in the water. A debate developed around the reason for these differences, bringing the already brewing interest in bubbles well into the mainstream.
At the time, all tables were based upon dissolved gas models like Buhlmann, and thus not directly modeling bubble development during an ascent. Dissolved gas models preference ascents that maintain a reasonably high gradient between the gas in tissues and the gas being breathed, which should be supportive of efficient elimination from tissues. Dissolved gas models manage—but do not explicitly control for—bubbles and were thus labeled (probably unfairly) as “bend and mend” tables. In fact, dissolved gas models are designed to limit supersaturation (explicitly), because this is supposed to limit bubble formation. Haldane references this control of supersaturation in his pioneering publication .
Those advocating for different ascent protocols imagine that a lack of deep stops creates more bubbles, which then need to be managed during a longer series of shallow decompression stops. In this scenario, a slower ascent from depth, including “deep stops,” would reduce the formation and growth of bubbles while reducing time that might otherwise be needed to manage previously formed bubbles. Support for these ideas gained momentum in diving and professional communities, although some of these individuals were arguably conflicted by a vested interest in promoting deep stop models. Eventually, the practice received more critical consideration but during the intervening years deep stops were largely considered as common knowledge.
The idea of controlling bubbles became extremely popular through the 1990s, encouraging deeper stops designed to limit bubble formation and growth. The “test-and-see” approach developed by early tech divers appears to have fueled the promulgation of deep stops though the determining characteristics remained poorly defined. Early tech divers embraced the uncertainty of their activity, realized that nobody had the answers, and decided to “experiment” in search of their own answers. In fact, divers were experimenting with a lot more than deep stops, altering gases breathed, the placement of various decompression stops, and the total amount of decompression time utilized. This meant that divers were sometimes aggressively adjusting multiple factors simultaneously.
For example, divers using a decompression program might input significantly less helium than was present in their breathing mixture. This was done because the algorithm increased decompression time with elevated helium percentage, sometimes known as the helium penalty . In other cases, divers would completely change the structure of stop times. For example, divers would invert the way a profile should be conducted by doing more time near a gas switch and less time prior to the next gas switch, believing the higher-oxygen gas only 3m/10ft away was time better utilized.
I do not intend an exhaustive or detailed review but only to assert the many, sometimes radical approaches being taken by tech divers who often perceived success with these various strategies. In some cases, it appears these practices may have been leading the way toward improvements (eliminating the Helium penalty) while other adjustments might prove disadvantageous. In both cases, it is important to note that divers understood—or should have understood—these actions to be potentially dangerous, accepting risk as a natural part of pushing into uncertain territory where definitive guidance and clear borders are rarely available.
None of this is to argue that divers should engage in aggressive decompression or challenge convention or place themselves at risk to unknown complications. I merely wish to clarify the atmosphere under which these adjustments were conducted, while highlighting that conventional ideas of risk mitigation are inherently complicated against a backdrop of novel exploration. A sense of relative risk dominated most of these trials since there are also risks associated with lengthy, in-water exposure. Eliminating what might be an avoidable decompression obligation could reduce risk from other obvious factors, including changing weather, dangerous marine life, being lost at sea, hypothermia, and oxygen exposure. Decompression experimentation was but one of many attempts to establish new protocols during extensive exploration projects.
During this time, deep stops and similar adjustments were part of the “norm” for aggressive technical explorers who were sometimes notably reducing in-water time as compared to available tables. It is interesting to note that individual differences in susceptibility seemed among the most prominent variables across the range of tested adjustments, and we will return to this in a later discussion. For now, we should acknowledge that the “success” being achieved (or imagined) is greatly complicated by a small sample size of self-selected individuals who were simultaneously experimenting with a range of variables. On the other side, I do not want to entirely discount the results being seen by these divers. We should remember that development of safe decompression ascents for the general diving community was not the goal of most tech divers. These divers were interested in maximizing their personal and team efficiency during decompression. These strategies may or may not have been objectively successful or broadly applicable, but many teams imagined them so, at least within the narrow scope being considered. Later, we will return to these important distinctions with careful consideration for the potentially different interests being pursued by divers evaluating different decompression profiles.
Fortunately, a desire to create broadly useful tools was high on the list of priorities for some individuals in the technical diving community, leading to a relevant and important contribution. This inventive approach would introduce a new way to think about decompression, remaining to this day at the center of the debate about deep stops.
Creating a New Baseline
Despite the popularity of deep stops and other modifications presented previously, technical divers lacked a common language for comparing the results, especially across different profiles. Compounding this problem was the variable way decompression programs considered a dive to be more or less “safe.” For example, some programs developed “safety factors” which increased total decompression time by an arbitrary factor, i.e., made them 10% longer. Other programs used different strategies, though it was not clear whether any of the various safety factors actually made the decompression safer. Whether safer or not, these factors were typically inconsistent and added complications when comparing various profiles. Just as these debates were reaching a fervor, help arrived from an unlikely place. An engineer by trade and decompression enthusiast by choice, Erik Baker had developed a novel solution.
Baker was seeking a way to establish consistency in considering the safety or lack of safety between various profiles. The term Baker applied was Gradient Factor (GF). I will not invest considerable time exploring the science behind GF, as many useful resources are widely available. For our purposes, it is sufficient to say that GFs allows a user to establish a lower threshold than the maximum recommended by a dissolved gas algorithm. This maximum pressure or M-value is assigned to “compartments” having an assumed amount of tolerance relative to the flow of blood they receive. Decompression theory is complicated by many factors but when the pressure of a gas in a compartment nears the M-value, it is thought that the risk of decompression sickness becomes higher. By adjusting a profile through the use of GF, one presumably reduces the risk. However, this also means there is less gradient between the gas in tissues and the gas in blood, reducing the driving force for the removal of gas and probably requiring additional decompression time.
Gradient factors took an important step toward using a consistent language when talking about a variety of adjustments divers might make to their decompression. As part of his work on GF, Baker had developed a keen interest in the decompression adjustments by leading technical divers. Baker and I began working together while evaluating some of our most extreme diving profiles. This collaboration led to a number of productive developments including GUE’s DecoPlanner, released in 1997, and among the first to utilize GF methodology. These collaborations further highlighted what appeared to be a discrepancy between the decompression expected by dissolved gas algorithms and the decompressions being conducted by many technical divers.
Decompression experimentation tended to cluster in small groups whose size was likely affected by self-selection with members who would stop or reduce aggressive dives when experiencing decompression sickness. Yet, it seemed possible that there was more to the story. These divers were doing several things that should have exposed them to notable risk and yet were repeatedly completing decompressions of more than 15 hours. Deep stops were only part of the story as these divers were ignoring conventional wisdom in several areas while notably reducing decompression time. What was behind this discrepancy? Were deep stops right or wrong? Was the conservative approach to helium right or wrong? Were these individuals lucky? Were they unusually resistant to decompression sickness, or were there other factors lurking in the background?
Note: I will outline many of these developments in the upcoming Part Three, where we more directly consider the modern challenges to deep stops and most especially the assertion they are dangerous. In the interim, I hope to hear from our readers. Do you have different experiences from this period? Do you think such experimentation is reckless or inadvisable? Please let us know your thoughts.
Jarrod is an avid explorer, researcher, author, and instructor who teaches and dives in oceans and caves around the world. Trained as a geologist, Jarrod is the founder and president of GUE and CEO of Halcyon and Extreme Exposure while remaining active in conservation, exploration, and filming projects worldwide. His explorations regularly place him in the most remote locations in the world, including numerous world record cave dives with total immersions near 30 hours. Jarrod is also an author with dozens of publications, including three books.
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