Conshelf

Jacques-Yves Cousteau

Jacques-Yves Cousteau carried out three pioneering projects with underwater stations between 1962 and 1965 under the name Conshelf or Précontinent .

Origin of name

Précontinent is the French word for continental shelf and describes the mostly marginal area of ​​a continent that is covered by the sea. The English equivalent is continental shelf , whose short form Conshelf was also used as the name of the project.

Conshelf I or Précontinent I

Scheme of Diogenes

Project Conshelf I took place in the period 14. – 21. September 1962 off the coast of Marseilles . The habitat used for this was named Diogenes after the dwelling of the Cynic philosopher, known as " Diogenes in the bin ". The habitat consisted of a steel cylinder with a length of 5 m and a diameter of 2.5 m and had a television, radio, library and a bed. It was anchored to the sea floor at a depth of 11 m with the help of large iron bars and heavy chains and had an entrance hatch in the bottom that gave the two aquanauts Albert Falco and Claude Wesly easy access to the sea.

Ships on the water surface supplied the habitat with hot water through plastic pipes. Food was transported in watertight containers called transfer pots . All other life support systems, consisting of electricity for infrared lamps that served as heating, radio and record player, three telephones and a video surveillance system, were fed in from a land station on the nearby island of Frioul. 30 people monitored the project and the health of the crew from the surface.

Compressed air was used as breathing gas both in the house and in the diving equipment during the excursions. The men worked in the water for up to five hours at a time and descended up to 55 meters. The water temperature ranged between 16 and 21 ° C.

mission

During the 7-day mission on the ocean floor, Falco and Wesly built fish houses out of cement blocks and constructed fish enclosures out of steel grids. Caught fish were placed in these enclosures and their behavior was photographed there. The aquanauts also undertook studies of underwater topography, where it was necessary to measure depths and distances and calculate the resulting angles of inclination. This data was used to design a simple grid network at a depth of 10 m and a second at 25 m. This grid represented the limits of the diving excursions.

The men underwent daily medical examinations that included construction tasks at a table in the water outside the habitat. Similar tasks were performed in the habitat for two hours each evening.

target

The objectives of Conshelf I and Conshelf II and III, which were to follow soon after, were described as follows:

1. Calculation and practical study of the coefficient for a useful duration, defined as: ${\textstyle {Tauchzeit\ (also\ die\ Arbeitszeit) \over Tauchzeit\ +\ Aufstiegszeit}}$

2. Determine the conditions for extended dives, especially the breath mixes used and their disadvantages

3. Showing the lack of short and long term damaging effects of such saturation dives.

End of mission

The decompression procedure, which was performed on the seventh day, required the two aquanauts to breathe a mixture of 80% oxygen and 20% nitrogen in the habitat for three hours while they were still on the sea floor. This period was interrupted by a symbolic pause at 3 m, after which they surfaced without further decompression.

Documented problems

• The medical examinations of one hour per day in the habitat were reduced towards the end of the experiment because they were too tiring for the aquanauts.
• Albert Falco's numerous nightmares and irritability diminished after Cousteau reduced the intervals between disturbances and visits.

Conshelf II and Précontinent II, 1963

Starfish

On June 15, 1963, Project Conshelf II began in the Red Sea near Sha'ab Rumi, Arabic for Roman reef, northeast of Port Sudan . The goal was to station five people for four weeks at a depth of 11 m using air as their breathing gas. In addition, two men lived at 27 m for a week. In addition to an enlarged team, Conshelf II had another focus: to extend the length of stay, to demonstrate the feasibility of habitable structures, to prove the possibility of using various underwater tools and to use a propeller-driven submarine for two people.

In 1964, the award-winning film Le monde sans soleil (French for world without sun ) was made about the project.

Components

Starfish House : This main structure of Conshelf II measured 10.4 m at its widest point and consisted of a central unit with four cylinders measuring 1.2 × 2.4 m. Starfish House contained sleeping arrangements, a living and dining room, sanitary facilities and a room for diving preparation. This arrangement was a significant advance over the Conshelf I Habitat. The construction rested on 2 m long telescopic legs that could be adapted to the ground. A ballast amount of 100 t was necessary to generate the necessary negative buoyancy. These were generated from 2000 lead bars of 45.4 kg each, which had to be positioned by hand by the divers. The internal temperature was kept at 26.7 ° C. and the humidity at 85%.

Deep Cabin : This habitat in the shape of a cylinder with a diameter of 2 meters on a tripod made of telescopic legs had two rooms vertically one above the other. The lower room housed diving equipment, tools and the open hatch to the sea. The upper room served as the living area and contained two bunks, a kitchenette, an intercom, a telephone and a surveillance camera connected to a monitor in the Starfish House. The deep cabin aquanautsbreathed a mixture of 50% helium and 50% air.

garage

Garage : This underwater hangar was used as a garage for the Hydrojet diving discus Diving Saucer . The interior of the hangar was flooded with air so that the diving discus could be lifted completely out of the water while one was still 11 meters below the surface of the sea. This enabled the crew to get out of the submarine, service the vehicle, charge the batteries and perform other work on the surface regardless of the weather conditions. Air for the hangar came from the same ship that supplied Starfish House

Equipment shed : Fish traps and other items of equipment were stored in this water-flooded shed.

SP-350 Diving Saucer

Hydrojet Saucer DS-2 : This was a submarine for two people in the form of a discus with a maximum diving depth of 350 m for dives of four to five hours. Thanks to the garage, it was no longer necessary to bring the DS-2 to the surface and was therefore independent of the weather conditions. It had been developed by Jacques-Yves Cousteau and the engineer Jean Mollard at the French Center for Undersea Research and was given the name Diving Saucer ('diving saucer') instead of the formal original name SP-350 Denise , because it is in its shape of a flying one Saucer resembled. It had a diameter of 2.85 m and a weight of 3.5 t. Thanks to its jet propulsion, it reached a speed of two knots or 3.7 km / h. It had three movable outside lamps, two cameras, a radio, a cassette recorder and a gripper arm that could be controlled from the inside. In 1965, two more and more advanced mini-submarines called Sea Flea ('Sea Flea') were developed, designed for depths of up to 500 meters.

crew

Deep Cabin

In the main house Starfish:

• The director of the underwater station Raymond Vassiere (38) from the Oceanographic Museum in Monaco
• Head diver Claude Wesly (30)
• Industrial designer André Folco (33)
• former customs officer Pierre Vannoni (31)
• and as boss Pierrot Guilbert (43)
• Parrot Claude

In the Deep Cabin laboratory :

• Raymond Kientzy (33)
• André Portelatine

mission

Raymond Kientzy and André Portelatine stayed in the Deep Cabin for a week and during this time undertook routine excursions to a depth of 50 m and three more to 110 m. During these dives, they breathed compressed air.

One of the main goals was to collect and observe fish and other marine organisms. The collected objects were used for exhibition and study in the Monaco Oceanographic Museum. The aquanauts positioned fine, close-meshed nylon nets and traps on various reefs in order to catch the fish without injuring them. Some of these were then placed in clear plastic bags where they could move around freely.

During the mission, aluminum-coated wetsuits were used, which should be visible from afar. In the event of an unintentional appearance of an aquanaut, this should be able to be found as quickly as possible so that a rescue operation can be initiated immediately.

60 employees monitored the mission ashore. Food was brought to the habitat by couriers and a doctor examined the condition of the aquanauts twice a day.

On the surface of the water, the project was supported by the supply ship Rosaldo, while the Calypso took over the shuttle service between the dive site and Port Sudan.

financing

The entire program was funded with US $ 1.2 million from the French Petroleum Agency. Cousteau had stated in advance that drilling platforms on the seabed were safer and cheaper than platforms on the surface and that the continental shelf had undiscovered minerals, the mining of which would be within reach thanks to the Conshelf experiments.

End of mission

At the end of seven days, the breathing gas of the aquanauts in the Deep Cabin was switched to 50% nitrogen and 50% oxygen each for a period of 3.5 hours before returning to the Starfish House, which was still anchored at a safe depth of 11 m. Two members of the Starfish House crew and Madame Cousteau had previously decompressed to make room for the Deep Cabin crew. After an overnight stay in the Starfish House, Kientzy, Portelatine and the remaining members of the Starfish House crew used the following decompression procedure before surfacing:

Time (in minutes)	Breathing gas
15th	80% O 2 /20% N 2
15th	air
30th	80% O 2 /20% N 2
30th	air
60	80% O 2 /20% N 2
popped up

Documented problems

• Because no air conditioning was used in the Deep Cabin, the inside temperature rose to that of the surrounding water, namely 29.4 ° C with a humidity of 100%. This environment, along with other adverse circumstances, resulted in severe loss of appetite and insomnia.
• When Deep Cabin lost pressure, the water level rose 40 cm per day. This rise continued until it was discovered that a leak had occurred in the routing of a television cable, which was then sealed.
• The narrow ledge that Deep Cabin stood on proved very problematic during placement. Several times she fell off the edge, once even with the two aquanauts in her. Finally it was secured with special mooring cables and anchors.
• In addition, problems arose with regard to placement, ballast, defective anchoring and breaking of habitat support legs. However, no one was injured in any of the problems.
• In the final report of the 1964 Sealab I program, it was noted that the Aquanauts of Conshelf II " had moderate anemia after prolonged exposure to compressed air at seawater depths of only 32 feet ."

Conshelf II Garage 2017

Current condition

Photos from 2014 and 2017 show that the now heavily overgrown garage is still in its original location and is filled with air above the portholes. The air lock that can be seen suggests a buoyancy of several tons, which is still held by the construction after 51 years. The remains of the equipment shed and some of the shark cages are also on site.

Conshelf III or Précontinent III

Conshelf III

The Conshelf III habitat consisted of a spherical structure 5.5 m in diameter divided into two floors. The lower floor contained diving, sleeping and sanitary facilities; the upper floor was reserved for eating, communication and data collection. The steel ball rested on a 14.6 × 8.5 m boat with 77 tonnes of ballast, water ballast tanks and storage bottles with helium, oxygen and compressed air. There were also two small decompression chambers on the boat. Each of them had space for three people and could be detached from the boat in an emergency in order to bring the aquanauts to the surface in the function of underwater lifeboats. The entire system including the boat weighed 140 tons.

Project Conshelf III cost $ 700,000, required 150 people and a dozen ships. It resulted in Cousteau going into deep debt. Still, he called it "one of the first steps towards economic occupation of the seabed".

Beginning of the mission

The project was scheduled to begin on September 17, 1965. The celebrations were carried out, the habitat was sealed and the aquanauts were compressed to 100 m. The habitat was towed to the dive site and preparation for the dive began. Now the weather and damaged power and communication lines tilted from the shore, so that the habitat was towed back to the port of Monaco, where the aquanauts remained under pressure within the facility for four days while the damage that had occurred was repaired. Then Conshelf III was towed back to the dive site with the help of five ships, the diving saucer and half a dozen launches and rubber boats.

At the same time as the American Sealab program, the Conshelf III project began on September 21, 1965 in front of the Cap Ferrat lighthouse near Monaco at a depth of 100 m. This should be the start of a 22-day seabed experiment. The Conshelf team consisted of six men led by André Laban.

A year of training, testing and construction had passed beforehand. This included experimental dive simulations, including prolonged exposure of sheep and goats to depths of 200 m with helium-oxygen mixtures as breathing gas. After the successful completion of these studies, an experiment was carried out for which Dr. Charles F. Aquadro and Dr. Jacques Chouteau spent three days in a chamber equivalent to 122 m of sea water.

mission

The water temperature outside the habitat was 10 to 12.8 ° C. Inside the facility, the temperature was kept at 32.2 ° C due to the high thermal conductivity of helium and was therefore slightly higher than that chosen by the aquanauts in Sealab II.

Conshelf III's life support systems represented a significant advancement. The breathing gases circulated through a refrigeration generator (cryogenerator) that freezes the carbon dioxide and other harmful gases and acts as a dehumidifier and freezer. The system also had gas analyzers that could be monitored both in the habitat and in the control station in the shore lighthouse. This system was supported by a greatly reduced mass spectrometer that controlled all gases in the habitat.

The breathing gas both within the habitat and during the diving excursions consisted of 2.5% oxygen and 97.5% helium. Most of the dives were done with hookah tubes and reserve tanks intended for emergencies or short dives. Vertical excursions were limited to 10 m above and 25 m below the saturation depth of 100 m.

The hookah tubes actually consisted of two lines. One transported breathing gas from the habitat to the aquanaut and the other the exhaled gas back to where the CO _{2 was} removed and oxygen was added. Cousteau described it as follows: " The oceanaut at the end of this gigantic breathing system wore two wet suits made of foam rubber, our new two-way regulator for high-pressure heliox on his chest and a conventional diving device with a heliox filling on his back " .

In order to protect the aquanauts from the cold, they wore specially produced rubber vests containing small hard rubber balls. This did not affect the thermal insulation due to higher pressures, as is the case with neoprene suits. But despite these vests, diving time was limited by the cold and not by exhaustion.

One of the primary tasks performed during the Conshelf III mission was to assemble components of a petroleum wellhead, a vertical stack of pipes and valves called a Christmas tree. In order to make the work project look more realistic, it was provided with compressed air bottles to generate internal pressure and thus simulate a working drill head. The aquanauts were instructed to perform a series of complicated and arduous jobs including threading a stiff wire through a thick pack of pressure-resistant gaskets and replacing a 180 kg valve that was pressurized to 176 kg / cm² (2500 psi) . This last job was completed in 45 minutes, faster than it had ever been completed on land by experienced oil drilling hands. During this work the divers were periodically supported by the Diving Saucer.

The average time spent in the water was 2½ hours per day with a diver maximum of seven hours in a day.

Although Conshelf III was planned for two weeks, the program was extended to 22 days. During this time the program was plagued by equipment and technology failures.

End of mission

Calypso, 1980

On the evening of the 22nd day (October 13, 1965) the ballast was released and the water ballast tanks were flooded with air. The habitat began to emerge and was under the complete control of the aquanauts in the interior and the diving saucer as an observation platform during the three-minute ascent. The total bottom time for Conshelf III was 21 days, 17 hours and 16 minutes. The aquanauts began their 84-hour decompression within the habitat while the supply ship Calypso towed it to Monaco harbor. Including the decompression time and the four days of waiting at the beginning, they had been under pressure for 30 days, 10 hours and 52 minutes. Apart from exhaustion, the long stay on the sea floor and the long decompression had no negative medical effects. After the lack of further sources of funding, the mission series was discontinued, although six projects were initially planned.

Documented problems

• Bad weather conditions delayed the start of the mission by four days.
• On the fourth day, a strong storm hit the dive site and became the largest recorded in the area since 1947. The storm stalled some seabed projects and damaged the frame that carried the cables for power and communication between the habitat and the shore. This damage was repaired during the storm, so it was not necessary to switch to emergency power and bring the aquanauts to the surface prematurely. The aquanauts were insensitive to the effects of the storm, even though the waves were so great that the water level in the habitat entrance rose and fell by 5 cm. This made it necessary to constantly equalize the pressure of the ears due to the changing pressure in the habitat.
• A chronic problem that Sealab II had to contend with and that also occurred in Conshelf III was constant leaks through which helium escaped into the electronic devices. This also caused damage to the surveillance camera. Sealab II solved the problem by placing the cameras outside the habitat and pointing them through the panes at the interior. In Conshelf III instead, the picture tubes were changed every few days, which cost an average of 250 US dollars per day.
• The now common problem of difficult communication in a helium atmosphere reappeared. The most reliable solution to this was written messages that were sent to the surface by holding them in front of the camera or using an electrowriter, a device that transmitted the movements of a special pen through a cable simultaneously to the surface, where another pen carried out the movements translated into writing.

Conshelf IV and V

Conshelf IV should accommodate 5 people for 2 weeks at the same depth as Conshelf III, i.e. 100 m, but they should undertake excursions at depths of up to 175. The habitat should also be less dependent on the surface supply.

Conshelf V was planned for 1966 at a depth of 193 m, from which the 5 aquanauts should undertake excursions down to 295 m.

Neither Conshelf IV nor Conshelf V were ever implemented. Instead, in October 1968, Cousteau signed a contract with the French government to develop Argyronète, a mobile habitat that was supposed to be surface independent.

Individual evidence

1. ↑ ^{a b c d e} James W. Miller, Ian G. Koblick: Living and Working in the Sea . Van Nostrand Reinhold Company, New York 1984, ISBN 0-442-26084-9 , pp. 30-37 .
2. ^ ^{A b c} Cousteau.org: Conshelf I, II & III. (No longer available online.) Archived from the original on June 9, 2014 ; accessed on September 2, 2016 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  
3. ↑ ^{a b c d e f} Ned Middleton: Conshelf - Cousteau's Cutting Edge. Beyond The Blue, archived from the original on May 10, 2007 ; accessed on September 7, 2016 (English). 
4. ^ Cousteau.org: Denise was her original name ... Retrieved September 7, 2016 (English). 
5. ↑ 40 years of "Précontinent II", life under pressure . Diving magazine, September 2003, p. 70-73 .
6. ↑ Ute Eberle: Space stations in the interior of the world . No. 66 . MARE magazine, Hamburg 2008, ISBN 3-936543-56-9 , p. 96 .
7. ↑ Sealab I Project Group: Project Sealab Summary Report: An Experimental Eleven-Day Undersea Saturation Dive at 193 Feet . ONR Report ACR-108. Office of Naval Research. Dep. of the Navy, Washington, DC June 14, 1965, p. 36 .
8. ↑ Amar and Isabelle Guillen: Remains Précontinent II Conshelf II. Accessed September 7, 2016 . 
9. ↑ UMEX: Sudan Liveaboard Classics. Retrieved August 18, 2017 . 
10. ^ ^{A b} Axel Madsen: Cousteau: An Unauthorized Biography . Ed .: Open Road Media. March 17, 2015 ( google.com ).