Cave diving disaster with 4 minutes of air | The Shaft Sinkhole Diving Tragedy

[Music] in the deadliest day of cave diving in Australia four family members went on a cave diving Adventure but only one returned this is the Fatal breakdown of the shaft diving tragedy Christine Millet was a prodigy at only 19 years old she had literally been diving for nearly 15 years according to her father he was a professional diver in Australia and raised his kids in the water diving Christine Steven and Glenn were legitimate scuba diving experts in the spring of 1973 they had each achieved the highest scuba qualification available and Christine was the current New

South Wales title holder In Scuba the millets were a formidable team of expertise and an excellent addition to any diving outing their cousin John bockerman was also an experienced diver but with just four years of experience under his belt he was considered the novice of the family on May 28th 1973 a group of nine had planned a two-day dive in Mount gambir at the shaft sinkhole this sinkhole was unique in that just a tiny hole had broken through the ceiling of a huge Cavern below the hole was widened to about 3 ft to allow a

person to be lowered in with a rope ladder once you squeeze through the grassy hole the cavern opens to the surface of a lake 20 ft below it's quite deceiving that this innocuous little hole in the ground opens to a waterfill cave that's about the size of a football field on a sunny day the light from the opening beams through the water creating a shaft of light straight to the bottom the beam ends at the Sur surface of the rock pile 120 ft below this pile of rocks was an accumulation of rocks dropped in by

the land owners in an attempt to fill this hole in their pasture after thousands of stones were dropped in they realized the true vastness of the cavern below this pile of rocks and the shaft of light from above are the center anchors of the cave divers would always use the light from the entrance as the North Star to orient them within this interesting diving destination as long as you stayed out of the two tunnels that squeezed off each side of the cave you could see the hole above whether it was sunny or cloudy on day

one of their dive the group of nine members of the South Pacific diving Club of New South Wales dropped a line from the entrance down to the top of the rock pile this would be the only line they set that day eight divers explored around the main Cavern making it about halfway around the room before they ended for the day the ninth diver stayed at the surface to manage supplies and safety Robert Smith was the president of the diving Club and had been in the shaft more than 20 times he was comfortable with the chamber

they were exploring but Robert didn't know what Christine had in mind for day two as far as he had planned everyone agreed that they were staying in the 200t max depth range this would keep everyone within the main chamber and the hole above would be visible as a guide they hadn't laid any other guidelines nor had they made an official group dive plan without an established leader there was no coordination of plans or or a designated buddy system on the second day Christine Steven John and a fourth diver Gordon Roberts plan to enter the tunnel

section on the western edge of the cave and reach a depth of 250 ft they would bounce quickly down and back without spending any time at that depth setting a new record this was 1973 and scuba divers were still deep diving on regular air cylinders mixed gases were not yet introduced for recreational diving and Technical diving science had yet to be established scuba divers were limited to what depth could be achieved due to nitrogen Narcosis they were definitely testing the boundaries of what was possible and testing their own personal limits unfortunately the Dynamics of cave

diving were so different from Open Water scuba Christine John Steven and Gordon were all about to come face to face with these limits the other four divers Glenn Robert Larry and Peter all gave testimony as to what they witnessed and understood about the events of that day it appears that it all started normally the group entered the water and quickly Dove down to the floor of the room past the rock pile it didn't take long for Robert to start feeling light-headed because of nitrogen Narcosis as an experienced diver he recognized the symptoms immediately and moved

back up to a safer depth with the higher pressures of increased depth the nitrogen in the air is pushed into the bloodstream this has a narcotic effect similar to alcohol intoxication it can be extremely dangerous when you're d diving in a tunnel 200 ft under the water after moving around the base for a bit Glenn had noticed his time was nearly up he was just behind his sister and the others he reached out his hand to tap her shoulder letting her know that time was about up just before he contacted her back she lunged forward

with the others over the ledge at the edge of the room the ledge dropped off into the tunnel passage but Glenn wasn't too worried he figured they were getting a quick look then would be heading up as well as the individual divers followed their plans several made their way up towards the surface a few making decompression stops along the way before surfacing one by one they popped up at the surface but there were only four of them over a period of a minute or so which instantly became alarming they had all started with the same

amount of air and time was up a few of the divers went back down to see if they could locate the others even venturing down over the ledge but the only thing that was discovered was Steven's camera and flashlight sitting on the bottom it was an unbelievable situation that just couldn't be true they hoped that there was a pocket of Trapped air or some way that they could still be alive what happened down in that tunnel when Christine and the others reached the ledge hanging over the abyss they paused for a moment to gather their

bearings she knew that she would need to be quick get down and back with a minimal amount of time at this depth breathing normal Air at this depth was risky and she knew it even if she started to feel the first inclinations of nitrogen Narcosis she was conscious of how to manage this deficit she planned to stay focused on the task and keep breathing slow and measured at the Target depth the air is compressed so that each breath uses seven times more air than when breathed at the surface even if things went perfectly her Air

Supply would be gone in just minutes she was with her brother and cousin so as a group she knew they had the expertise to achieve the 250 ft depth record they were seen plunging into the depths of the tunnel starting around 200 ft to get to a depth of 250 they would have to travel over 300 linear feet down the ever narrowing tunnel to get to that depth as they moved along each person would have been experiencing a different level of dread their air was getting dangerously low and Narcosis was likely being felt but neither

of these problems was the true limiting factor it was the silt this wasn't something that they had experience with four divers in such a small space Disturbed The Long settled silt into a frenzy of plumes of sand that would take hours or even days to settle the silting reduced visibility to less than an arms length this was the deadly Crux without guidelines set how would you know how to get out Christine checked her air and realized that she would not make it to 250 ft turning back was not nearly as easy as it sounds after

swimming back through the cloud of silt there was no way to know exactly which direction would lead her back to the rock pile and the glow of the ceiling hole in that room on a cloudy day the tunnel would have no view of the main entrance hole she reached out in front of her but ran into rock formations that could have been the wall of the passage or just a boulder on the floor there was no way to orient herself now that silting had filled the entire tunnel her oxygen was running dangerously low and she

knew that making it back to the surface would barely be possible if she found the way out immediately in a desperate attempt to find the direction of the passage she shot up toward the ceiling to clear the the silted bottom Gordon was doing the exact same thing and they were seen down in the tunnel swimming to the ceiling of the passage their flashlights were frantically sweeping up and down then back and forth trying to see any sign that would lead them in the right direction there were uneven rocks jutting out and down from the upper

boundary so no simple smooth Rock to Glide along towards the upper part of the passage Christine and Gordon didn't know it but they were trapped in a false Dome over this portion of the tunnel once they were inside they they each spun around and felt along the Rocks looking for the way up imagine frantically feeling the ceiling and walls of Rock all around you but finding no way out all of this Panic completely blinded by opaque Sandy water all around at this point there was no way to reorient to East and West they only knew

that they were at the top of the tunnel because bubbles were collected in the many crevices but not enough to save them the Frantic nature of their efforts rapidly depleted the remaining air and sadly they would not get out of that Dome together they ran out of air became hypoxic and eventually sank down to the passage floor during this time Jon was seen quickly swimming with purpose farther down the wrong way inside the tunnel he was very likely suffering from nitrogen Narcosis as he swam deeper into the abyss Steven had turned around as well but

he was ahead of Christine and Gordon he too was running out of air and struggled to orient himself with no rope to guide through the opaque Waters he was later found with his buoyancy vest inflated this would have been a last ditch emergency method to get himself to the surface when his air was gone unfortunately he was caught up on an outcropping of rocks and never made it to the surface despite an exhaustive search by the surviving divers and police it took more than 11 months to locate and recover the four lost divers it was

truly hard to comprehend that some of the best trained scuba divers could lose their lives in a sinkhole after this disastrous day new standards began to be established specifically for cave diving the very real differences between open waterer diving and Cave Diving were essential facts that divers needed to be educated about thoroughly before they entered any cave current standards and best practices would require cave certifications for all members a leader to lay out a dive plan divers paired with a buddy safety divers at depth intervals extra tanks along the plan dive use of mixed gas

to reduce nitrogen Narcosis and guide guidelines to be laid prior to new exploration or record attempts much of this was established after their tragic loss and partly because of it the risky hobby of cave diving again claimed more lives in an unexpected moment of tragedy