In a world thirsting for wealth & strapped by the necessity of petroleum it was inevitable the search for recoverable reserves would take the oil industry into the wilds of the offshore oceans.
So it was in the fall of 1982 when I joined the diving crew of the Sedco 706, a semisubmersible deepsea drilling platform operated by Mobil Oil. The 706 was drilling exploratory wells offshore Newfoundland in an attempt to realize the full extent of the Hibernia oil find, discovered several years previous. Their quest was taking them ever farther out into the Grand Banks, that large area of continental shelf extending offshore from the coast. 250'...500'...& now 730'...Cha-ching!!
I could not believe my good fortune...only two years out of dive school & here I was, zipping up my survival suit in preparation to board the huge Okanagon helicopter for the two hour ride out to the rig. Normally, a diver of my limited experience would not see such a plum contract for several more years, but I had an ace in the hole. Part of my two year Associate of Science degree program in Underwater Technology was certification as a Diver-Medic. Very few schools were offering this training & I was one of two divers in my area with the ticket when the call came in...
And the other guy was out of town.
Beauty.
I worked for Can Dive Services, a Canadian subsidiary of the giant diving contractor "Oceaneering International." Oceaneering required a Diver-Medic in saturation at depths below 600'. As the 706 was moving from 500' to 730', I was offered the opportunity to be part of the deepest sat. dive ever conducted in Canadian waters.
I told them I thought I could fit them in.
During the flight out I recalled the tragedy of the "Ocean Ranger", another semisubmersible rig ( the largest in the world at the time ) which foundered in a horrific gale some 10 months earlier, not 10 miles from the vessel I was about to join. 84 men bailed into the sea that night, clad in nothing but jeans & t-shirts, as the rig sank in 250' of cold North Atlantic water.
There were no survivors.
I snapped out of my melancholic reverie as the helicopter began to circle the 706 in preparation for landing, affording me my first glimpse of the massive structure. From the crowded main deck rose the giant derrick, a structure designed to fascilitate the coupling, uncoupling & storage of the long stands of drill string used to "make hole." The upper framework of the vessel is supported by 8 huge cylindrical legs or "caissons," connected at their bases to two equally massive, laterally mounted pontoons. Within these catacombed pontoons are the pumps that act to shuttle water between compartments to provide even trim for the rig. Ballast water can be pumped in or out of these pontoons to settle the rig higher or lower in the water. Deck loading is an equally critical factor in vessel stability & is the sole preserve of the barge master. This enormous floating work platform is held in place by 8 massive anchors. Pontoon mounted thrusters provide propulsion for surface sailing & assist the rig to remain on station in weather.
Making hole in the seafloor is a multi-stage process.
At certain times in a routine "drilling program," human hands ( or robotic arms, nowadays ) are needed. When things screw up, divers become very important commodities, as the cost of drilling offshore is astronomical & time is money ( for a primer on offshore drilling, read the thread "If the bottom is firm, why does it squirm? ). The rig was proceeding to its' next drilling location & it would be several days before they were ready to "spud in" the new well. The initial phase of the drilling process would require divers on bottom thus the entire ship's company would be busy preparing for the work ahead.
After settling into my quarters I was introduced to the diving crew & together we set off to review the saturation diving system. The centerpiece of any sat. system is the "tankage", a series of pressure vessels (chambers) flange mated together. When the 706 was constructed, a Reneau "B" 1000' sat. system was built into the main deck, adjacent to the drilling moonpool. The tankage consisted of a 4 man living chamber, T.U.P.C. ( transfer under pressure chamber ),secondary 3 man living chamber ( for emergency use ) & the S.D.C. ( submersible decompression chamber or "diving bell" ). Only the bell would enter the water, the remainder of the system being fixed to the rig. Chamber atmosphere, depth, communications & environmental control were all housed in the "control van". The contributing sub-systems included hydraulics, pneumatics, electrics, electronics & various compressors, pumps, generators & hot water elements. The bell was mated to the t.u.p.c. with a removeable, hydraulically actuated clamp. Between the bell & the t.u.p.c. was a "trunking space", essentially a 2' long, 36" dia. tunnel. To launch the bell, the divers would transfer from the t.u.p.c. to the bell thru this trunking space; hatches on each side would be closed & dogged & the atmoshere in the trunking would be vented to atmosphere. The clamp would be removed & the bell would track away from the t.u.p.c. on a hydraulically actuated skid. A bell moonpool door would open & the bell would be raised clear of the skid by a bell-handling winch, it would then be lowered 60' thru the "air interface" to the surface of the sea. Bell atmosphere, diver's breathing gas, electrics & hot water were supplied by umbilical from the control van. The bell also carried a number of externally mounted high pressure "onboard gas" bottles as emergency backup. Electrically powered CO2 scrubbers removed excess CO2 & hot water heaters kept the atmosphere warm in all system tankage. The e.c.u. ( environmental control unit ) was charged with the task of maintaining reasonable humidity levels in the system & gave us the most trouble.
As the "medic-in-sat.," it was my resposibility to inventory & ready all emergency medical supplies, perform pre-dive base-line medicals on the divers, & assist with general system readiness. Out on deck, huge supply boats hovered close in while cranes hoisted supplies onboard, including vast "quads" of breathing gas for the diving system. Pure helium, various pre-mixes & 100% O2 had to be analysed, manifolded together & plumbed thru to the control van. In the closing days before committing to sat., we worked around the clock in two 12 hr. shifts to insure all was ready when the call came to dive. At 0230 hrs. the green light was given to saturate.
"Building an atmosphere..."
Myself & two divers entered the living chamber & watched with a wee dram of trepidation as the outside tenders closed & dogged the hatch. With all hatches secure, compression of all tankage ( excluding the emerg. living chamber ) began on air and continued to a pre-determined depth where the desired PO2 was attained, the remainder of the press continued utilizing 100% helium. The metabolic consumption of O2 was made up as necessary to maintain a constant ppO2 of .45ata-.5ata. Compression to 710' fsw. ( storage depth ) took a little over 4 hours. PPO2 & PPCO2 levels, depth & the divers well being were continuously monitored by L.S.T's ( Life Support Technicians ) in the control van, and a continous log of all activity was kept.
while saturated, we were visually monitored 24 hrs. a day by video cameras ( ordinarily not an inconvenience, but I could never get used to having a b.m. on closed circuit t.v.! ). During the press we remained quiet, diligently observing one another for any indications of trouble. As we neared the 700' level, the increasing density of the atmosphere made breathing a bit of a chore & I remarked:"Man, this gas breathes like peanut butter!" Not an incredibly funny line by any stretch, but I sounded just like Donald Duck & the guys exploded into laughter. The noise they made cracked me up & we cackled on like a gaggle of drunken ducks until the supervisor requested we regain control. That remains the greatest sustained belly-busting laugh of my life.
At 710' we were up & moving stiffly about the complex, flapping towels up & down to agitate the somewhat stratified atmosphere. I say stiffly because the increased pressure had forced most of the sinovial fluid from our major joint tissues, causing friction as bone scraped against bone ( the condition, known as "compression arthralgia," would all but disappear in a few days as the fluid worked its way back in ). In time we realized we were quite hungry so we decided to order in ( all meals are "take out" in a sat. system! ). While saturated, all our meals , linen changes etc. etc. were "sent down" to us using a "medical lock"; essentially a small ( 1' dia.x 2' long ) thru-bulkhead transfer chamber, it had a hatch on each end. With the inner hatch closed, the outside tender could "take the lock" by venting it to surface. He would then load it up, close the hatch & radio us the go-ahead to take the lock back down to depth. we achieved this by opening a valve that would allow chamber atmosphere into the lock & compressing it back to storage depth. We would remove the contents, reload the lock with whatever we wanted to "send up", & radio topside to once again vent the lock to surface.
Our options for dinner were piped in over the comms. & for the next :20 I attempted to relate our menu selections. Though the control van was equiped with helium unscrambling radios, the technology had not advanced to the point where helium affected speech was intelligible. One had to aquire a "helium ear" to decipher the garbled squawking. After half an hour of guess work we had the job of ordering almost complete save for my drink order; I wanted milk, but no matter how many times I said it, it came out as "hmoinck". Finally, in desperation, I mustered up my best " Moooooooooooooo!" Oh! You want milk! Why didn't you say so!
Yeeesh.
The work began. The first order of business was to establish and level a guide base on the seafloor; no easy task as the bottom had the consistency of loon-poo. We soon settled into a daily routine. We were not required on bottom every day & we passed the time reading pulp fiction & intently studying a wide variety of medical journals that for some reason focused exclusively on the female anatomy. Once a day we would shower in the t.u.p.c. using a conventional showerhead. Waste water would collect in the bilge to be evacuated to external holding tanks at the conclusion of showering. Gang showers were necessary to save on helium as a significant amount of atmosphere was needed to flush the bilge. Strong anti-bacterial soap was used to ward off skin infections brought on by elevated humidity levels. The t.u.p.c. also contained the head. One day I tired of the video camera that stared intently at me as I did my business so I draped my towel over the porthole it stared thru. After several seconds a disembodied voice quietly said: "Dannnneee, what are you doin in there? What is it you don't want us to see Dannneee??" I insisted I was not pleasuring myself, that there were things in life that we shouldn't have to share, that the sanctity of the bathroom should not be violated...I was abruptly cut off when the Supervisor cut in & told me to get the *&%$ towel off the !@#$%*+ porthole!!
Aye Aye, sir.
Originally scheduled for 7 days, we had now been down for 15, with little progress on bottom. The diving had been frustrating but routine. The drillers were scratching their heads to come up with new ways to solve their problems. Day 16 began with an order to dive, but this day would not be routine, it was to be a day of near disaster.
A typical dive to the bottom ( a "bell run" ) ran 8 hours, with each man taking a 4 hr. turn in the water. In preparation to dive, the man who is to enter the water first crawls into the bell to perform pre-dive checks & to load any needed supplies. When all is ready, he returns to the t.u.p.c. to suit up with the other diver. Thermal protection is afforded by hot water suits. With both divers in the bell, all hatches are closed & dogged in preparation for the venting of the trunking space. I would stand by the outer hatch in the t.u.p.c. to verify a good seal & to observe the launching of the bell. On this day, as I stood by for launch I was confounded to see the supervisor race from the control van to the bell to a point where I could no longer see him. Hot on his heels were the l.s.t.'s & the outside tenders. I called out to topside to ask what was going on but received no reply. After what seemed an eternity, the Supervisor came over the radio, out of breath & thoroughly frightened. He informed me the divers were returning to the living chamber & I was to check them over. Several minutes later I understood why.
The bell has 4 hatches, two open outward, two inward. Hatches 1&2 are located on the side of the bell, 3&4 on the bottom. Between 3&4 is another "trunking space" that the diver must pass thru to enter the water. The bell is sent to bottom with hatch #3 open & tied back. As the bell enters the water & descends, the divers observe hatch #4 to insure it seals. Prior to launch, hatch #3 is closed. This hatch utilized a 1/4 turn valve to allow pressure equalization of the trunking space with internal bell pressure. As the divers entered the bell to make the dive, one of them unknowingly kicked open this valve, allowing bell atmosphere to escape prematurely into the trunking space. In effect, the bell was now rapidly ascending, & no one knew why. Outside the bell, people were scrambling all over in a desperate attempt to isolate the leak; inside the bell, the bellman was systematically closing all valving in sequence as per protocol for such an emergency.
In the protocol, hatch #3 equalization valve is the second last valve to be closed.
The bell ascended 110' in just under one minute.
The divers were shaken, stirred, but otherwise unharmed...for the moment.
After a time the divers re-entered the bell & made an uneventful run. With the divers back in the living chamber, the bell was brought to surface & the 1/4 turn valve was replaced by a rising stem type valve that could not be inadvertently kicked open.
We were now into our 23rd day of sat. & the weather had made a turn for the worse. An early winter storm was building & the entire vessel was battening down.
At the height of the storm, the rig was being battered by waves reaching 70'. The constant pounding of waves against the steel structure set the steel to singing, not unlike a high tension wire in a wind storm. The sound was amplified in the chamber as the vibrations reverberated through the thick steel bulkhead. I lay in my bunk & tried to relax. While the rig did not heave to & fro like a conventional ship, it did rise & fall in a strange sort of dance as the giant heave compensators on the anchor windlasses paid out & recoiled wire with the passing of each mountainous wave. Every so often a monster wave would create a cacaphony of torturous sound as it smashed into the hollow caissons. In those moments I waited breathless, convinced a caisson had collapsed from the pounding seas, anticipating the sickening list that would signal the end of days. On & on the storm raged & soon my mind was filled with dark images of disaster & death; for should the rig founder, I was surely doomed. Normal ascent from such depth took 5 1/2 days! Emergency ascent? 3 days! I knew the drill. Should the rig face imminent risk of sinking, we were to retreat to the bell, which would be lowered to bottom & abandoned. To survive, we had 24 hrs. of breathing gas, lung powered scrubbers, mummy-style sleeping bags & a transponder to signal our location. A rescue vessel would have to locate us, retrieve us & race us to shore to be mated up with a compatible decompression chamber before we asphyxiated, froze or otherwise expired.
Yeah.
Just when I thought I was going to go stark raving nuts, I remembered what a buddy had told me he did in such circumstances...he called it V.M.C., or "Vicious Mind Control." With all your mental powers, focus on the positive. Take yourself away from where you are & go somewhere nice. Breathe slow & deep. Concentrate...
After :5 minutes of that I ordered up some sedatives & passed out for the remainder of the gale. I called it :
"S.S.O.T.S.S" or "Sedated Sleep of the Scared Stiff!"
At the conclusion of our 28th day in sat. we began our ascent to surface. Around 470', both divers exhibited signs & symptoms of bends. The procedure is to halt the ascent & decend to depth of significant relief. The divers were then to breathe treatment gas ( higher PO2 ) for specified periods by b.i.b.s. ( built-in-breathing-system ) mask. After several treatment sessions the divers showed significant improvement, but not complete resolution of symptoms. It was decided to resume our ascent & continue close observation of the divers. On day 35 we emerged from our cocoon. The divers returned home for follow-up treatment. It was postulated that both divers formed bubbles during their unscheduled ascent in the bell.
I continued to travel out to the 706 for the next 2 years as regular diving crew. More adventures followed; why I remember a time when...
Best Fishes,
D.S.D.
So it was in the fall of 1982 when I joined the diving crew of the Sedco 706, a semisubmersible deepsea drilling platform operated by Mobil Oil. The 706 was drilling exploratory wells offshore Newfoundland in an attempt to realize the full extent of the Hibernia oil find, discovered several years previous. Their quest was taking them ever farther out into the Grand Banks, that large area of continental shelf extending offshore from the coast. 250'...500'...& now 730'...Cha-ching!!
I could not believe my good fortune...only two years out of dive school & here I was, zipping up my survival suit in preparation to board the huge Okanagon helicopter for the two hour ride out to the rig. Normally, a diver of my limited experience would not see such a plum contract for several more years, but I had an ace in the hole. Part of my two year Associate of Science degree program in Underwater Technology was certification as a Diver-Medic. Very few schools were offering this training & I was one of two divers in my area with the ticket when the call came in...
And the other guy was out of town.
Beauty.
I worked for Can Dive Services, a Canadian subsidiary of the giant diving contractor "Oceaneering International." Oceaneering required a Diver-Medic in saturation at depths below 600'. As the 706 was moving from 500' to 730', I was offered the opportunity to be part of the deepest sat. dive ever conducted in Canadian waters.
I told them I thought I could fit them in.
During the flight out I recalled the tragedy of the "Ocean Ranger", another semisubmersible rig ( the largest in the world at the time ) which foundered in a horrific gale some 10 months earlier, not 10 miles from the vessel I was about to join. 84 men bailed into the sea that night, clad in nothing but jeans & t-shirts, as the rig sank in 250' of cold North Atlantic water.
There were no survivors.
I snapped out of my melancholic reverie as the helicopter began to circle the 706 in preparation for landing, affording me my first glimpse of the massive structure. From the crowded main deck rose the giant derrick, a structure designed to fascilitate the coupling, uncoupling & storage of the long stands of drill string used to "make hole." The upper framework of the vessel is supported by 8 huge cylindrical legs or "caissons," connected at their bases to two equally massive, laterally mounted pontoons. Within these catacombed pontoons are the pumps that act to shuttle water between compartments to provide even trim for the rig. Ballast water can be pumped in or out of these pontoons to settle the rig higher or lower in the water. Deck loading is an equally critical factor in vessel stability & is the sole preserve of the barge master. This enormous floating work platform is held in place by 8 massive anchors. Pontoon mounted thrusters provide propulsion for surface sailing & assist the rig to remain on station in weather.
Making hole in the seafloor is a multi-stage process.
At certain times in a routine "drilling program," human hands ( or robotic arms, nowadays ) are needed. When things screw up, divers become very important commodities, as the cost of drilling offshore is astronomical & time is money ( for a primer on offshore drilling, read the thread "If the bottom is firm, why does it squirm? ). The rig was proceeding to its' next drilling location & it would be several days before they were ready to "spud in" the new well. The initial phase of the drilling process would require divers on bottom thus the entire ship's company would be busy preparing for the work ahead.
After settling into my quarters I was introduced to the diving crew & together we set off to review the saturation diving system. The centerpiece of any sat. system is the "tankage", a series of pressure vessels (chambers) flange mated together. When the 706 was constructed, a Reneau "B" 1000' sat. system was built into the main deck, adjacent to the drilling moonpool. The tankage consisted of a 4 man living chamber, T.U.P.C. ( transfer under pressure chamber ),secondary 3 man living chamber ( for emergency use ) & the S.D.C. ( submersible decompression chamber or "diving bell" ). Only the bell would enter the water, the remainder of the system being fixed to the rig. Chamber atmosphere, depth, communications & environmental control were all housed in the "control van". The contributing sub-systems included hydraulics, pneumatics, electrics, electronics & various compressors, pumps, generators & hot water elements. The bell was mated to the t.u.p.c. with a removeable, hydraulically actuated clamp. Between the bell & the t.u.p.c. was a "trunking space", essentially a 2' long, 36" dia. tunnel. To launch the bell, the divers would transfer from the t.u.p.c. to the bell thru this trunking space; hatches on each side would be closed & dogged & the atmoshere in the trunking would be vented to atmosphere. The clamp would be removed & the bell would track away from the t.u.p.c. on a hydraulically actuated skid. A bell moonpool door would open & the bell would be raised clear of the skid by a bell-handling winch, it would then be lowered 60' thru the "air interface" to the surface of the sea. Bell atmosphere, diver's breathing gas, electrics & hot water were supplied by umbilical from the control van. The bell also carried a number of externally mounted high pressure "onboard gas" bottles as emergency backup. Electrically powered CO2 scrubbers removed excess CO2 & hot water heaters kept the atmosphere warm in all system tankage. The e.c.u. ( environmental control unit ) was charged with the task of maintaining reasonable humidity levels in the system & gave us the most trouble.
As the "medic-in-sat.," it was my resposibility to inventory & ready all emergency medical supplies, perform pre-dive base-line medicals on the divers, & assist with general system readiness. Out on deck, huge supply boats hovered close in while cranes hoisted supplies onboard, including vast "quads" of breathing gas for the diving system. Pure helium, various pre-mixes & 100% O2 had to be analysed, manifolded together & plumbed thru to the control van. In the closing days before committing to sat., we worked around the clock in two 12 hr. shifts to insure all was ready when the call came to dive. At 0230 hrs. the green light was given to saturate.
"Building an atmosphere..."
Myself & two divers entered the living chamber & watched with a wee dram of trepidation as the outside tenders closed & dogged the hatch. With all hatches secure, compression of all tankage ( excluding the emerg. living chamber ) began on air and continued to a pre-determined depth where the desired PO2 was attained, the remainder of the press continued utilizing 100% helium. The metabolic consumption of O2 was made up as necessary to maintain a constant ppO2 of .45ata-.5ata. Compression to 710' fsw. ( storage depth ) took a little over 4 hours. PPO2 & PPCO2 levels, depth & the divers well being were continuously monitored by L.S.T's ( Life Support Technicians ) in the control van, and a continous log of all activity was kept.
while saturated, we were visually monitored 24 hrs. a day by video cameras ( ordinarily not an inconvenience, but I could never get used to having a b.m. on closed circuit t.v.! ). During the press we remained quiet, diligently observing one another for any indications of trouble. As we neared the 700' level, the increasing density of the atmosphere made breathing a bit of a chore & I remarked:"Man, this gas breathes like peanut butter!" Not an incredibly funny line by any stretch, but I sounded just like Donald Duck & the guys exploded into laughter. The noise they made cracked me up & we cackled on like a gaggle of drunken ducks until the supervisor requested we regain control. That remains the greatest sustained belly-busting laugh of my life.
At 710' we were up & moving stiffly about the complex, flapping towels up & down to agitate the somewhat stratified atmosphere. I say stiffly because the increased pressure had forced most of the sinovial fluid from our major joint tissues, causing friction as bone scraped against bone ( the condition, known as "compression arthralgia," would all but disappear in a few days as the fluid worked its way back in ). In time we realized we were quite hungry so we decided to order in ( all meals are "take out" in a sat. system! ). While saturated, all our meals , linen changes etc. etc. were "sent down" to us using a "medical lock"; essentially a small ( 1' dia.x 2' long ) thru-bulkhead transfer chamber, it had a hatch on each end. With the inner hatch closed, the outside tender could "take the lock" by venting it to surface. He would then load it up, close the hatch & radio us the go-ahead to take the lock back down to depth. we achieved this by opening a valve that would allow chamber atmosphere into the lock & compressing it back to storage depth. We would remove the contents, reload the lock with whatever we wanted to "send up", & radio topside to once again vent the lock to surface.
Our options for dinner were piped in over the comms. & for the next :20 I attempted to relate our menu selections. Though the control van was equiped with helium unscrambling radios, the technology had not advanced to the point where helium affected speech was intelligible. One had to aquire a "helium ear" to decipher the garbled squawking. After half an hour of guess work we had the job of ordering almost complete save for my drink order; I wanted milk, but no matter how many times I said it, it came out as "hmoinck". Finally, in desperation, I mustered up my best " Moooooooooooooo!" Oh! You want milk! Why didn't you say so!
Yeeesh.
The work began. The first order of business was to establish and level a guide base on the seafloor; no easy task as the bottom had the consistency of loon-poo. We soon settled into a daily routine. We were not required on bottom every day & we passed the time reading pulp fiction & intently studying a wide variety of medical journals that for some reason focused exclusively on the female anatomy. Once a day we would shower in the t.u.p.c. using a conventional showerhead. Waste water would collect in the bilge to be evacuated to external holding tanks at the conclusion of showering. Gang showers were necessary to save on helium as a significant amount of atmosphere was needed to flush the bilge. Strong anti-bacterial soap was used to ward off skin infections brought on by elevated humidity levels. The t.u.p.c. also contained the head. One day I tired of the video camera that stared intently at me as I did my business so I draped my towel over the porthole it stared thru. After several seconds a disembodied voice quietly said: "Dannnneee, what are you doin in there? What is it you don't want us to see Dannneee??" I insisted I was not pleasuring myself, that there were things in life that we shouldn't have to share, that the sanctity of the bathroom should not be violated...I was abruptly cut off when the Supervisor cut in & told me to get the *&%$ towel off the !@#$%*+ porthole!!
Aye Aye, sir.
Originally scheduled for 7 days, we had now been down for 15, with little progress on bottom. The diving had been frustrating but routine. The drillers were scratching their heads to come up with new ways to solve their problems. Day 16 began with an order to dive, but this day would not be routine, it was to be a day of near disaster.
A typical dive to the bottom ( a "bell run" ) ran 8 hours, with each man taking a 4 hr. turn in the water. In preparation to dive, the man who is to enter the water first crawls into the bell to perform pre-dive checks & to load any needed supplies. When all is ready, he returns to the t.u.p.c. to suit up with the other diver. Thermal protection is afforded by hot water suits. With both divers in the bell, all hatches are closed & dogged in preparation for the venting of the trunking space. I would stand by the outer hatch in the t.u.p.c. to verify a good seal & to observe the launching of the bell. On this day, as I stood by for launch I was confounded to see the supervisor race from the control van to the bell to a point where I could no longer see him. Hot on his heels were the l.s.t.'s & the outside tenders. I called out to topside to ask what was going on but received no reply. After what seemed an eternity, the Supervisor came over the radio, out of breath & thoroughly frightened. He informed me the divers were returning to the living chamber & I was to check them over. Several minutes later I understood why.
The bell has 4 hatches, two open outward, two inward. Hatches 1&2 are located on the side of the bell, 3&4 on the bottom. Between 3&4 is another "trunking space" that the diver must pass thru to enter the water. The bell is sent to bottom with hatch #3 open & tied back. As the bell enters the water & descends, the divers observe hatch #4 to insure it seals. Prior to launch, hatch #3 is closed. This hatch utilized a 1/4 turn valve to allow pressure equalization of the trunking space with internal bell pressure. As the divers entered the bell to make the dive, one of them unknowingly kicked open this valve, allowing bell atmosphere to escape prematurely into the trunking space. In effect, the bell was now rapidly ascending, & no one knew why. Outside the bell, people were scrambling all over in a desperate attempt to isolate the leak; inside the bell, the bellman was systematically closing all valving in sequence as per protocol for such an emergency.
In the protocol, hatch #3 equalization valve is the second last valve to be closed.
The bell ascended 110' in just under one minute.
The divers were shaken, stirred, but otherwise unharmed...for the moment.
After a time the divers re-entered the bell & made an uneventful run. With the divers back in the living chamber, the bell was brought to surface & the 1/4 turn valve was replaced by a rising stem type valve that could not be inadvertently kicked open.
We were now into our 23rd day of sat. & the weather had made a turn for the worse. An early winter storm was building & the entire vessel was battening down.
At the height of the storm, the rig was being battered by waves reaching 70'. The constant pounding of waves against the steel structure set the steel to singing, not unlike a high tension wire in a wind storm. The sound was amplified in the chamber as the vibrations reverberated through the thick steel bulkhead. I lay in my bunk & tried to relax. While the rig did not heave to & fro like a conventional ship, it did rise & fall in a strange sort of dance as the giant heave compensators on the anchor windlasses paid out & recoiled wire with the passing of each mountainous wave. Every so often a monster wave would create a cacaphony of torturous sound as it smashed into the hollow caissons. In those moments I waited breathless, convinced a caisson had collapsed from the pounding seas, anticipating the sickening list that would signal the end of days. On & on the storm raged & soon my mind was filled with dark images of disaster & death; for should the rig founder, I was surely doomed. Normal ascent from such depth took 5 1/2 days! Emergency ascent? 3 days! I knew the drill. Should the rig face imminent risk of sinking, we were to retreat to the bell, which would be lowered to bottom & abandoned. To survive, we had 24 hrs. of breathing gas, lung powered scrubbers, mummy-style sleeping bags & a transponder to signal our location. A rescue vessel would have to locate us, retrieve us & race us to shore to be mated up with a compatible decompression chamber before we asphyxiated, froze or otherwise expired.
Yeah.
Just when I thought I was going to go stark raving nuts, I remembered what a buddy had told me he did in such circumstances...he called it V.M.C., or "Vicious Mind Control." With all your mental powers, focus on the positive. Take yourself away from where you are & go somewhere nice. Breathe slow & deep. Concentrate...
After :5 minutes of that I ordered up some sedatives & passed out for the remainder of the gale. I called it :
"S.S.O.T.S.S" or "Sedated Sleep of the Scared Stiff!"
At the conclusion of our 28th day in sat. we began our ascent to surface. Around 470', both divers exhibited signs & symptoms of bends. The procedure is to halt the ascent & decend to depth of significant relief. The divers were then to breathe treatment gas ( higher PO2 ) for specified periods by b.i.b.s. ( built-in-breathing-system ) mask. After several treatment sessions the divers showed significant improvement, but not complete resolution of symptoms. It was decided to resume our ascent & continue close observation of the divers. On day 35 we emerged from our cocoon. The divers returned home for follow-up treatment. It was postulated that both divers formed bubbles during their unscheduled ascent in the bell.
I continued to travel out to the 706 for the next 2 years as regular diving crew. More adventures followed; why I remember a time when...
Best Fishes,
D.S.D.
