The Kilsby Sinkhole: A Dangerous Diving Location

LocationDiver Names
South Australia, Kilsby SinkholeBrett, Patrick, George, Carrie, Dr. Robert McAllister

Two incidents, one location – The Kilsby Sinkhole. Eighteen-year-olds Patrick and Brett decided to go to the Kilsby Sinkhole for a leisurely dive with their friends. They descended into the cave, and when the next diver tried to follow them, the safety line disappeared. Forty-one years later, a 52-year-old health practitioner was diving with his friend when he developed breathing problems 104 feet below.

Located on a picturesque sheep farm amidst the stunning rolling countryside of South Australia, just eight miles south of Mount Gambier, lies The Kilsby Sinkhole. This naturally occurring car sinkhole has been used for recreational diving, as well as civilian and police diver training, since the late 1960s. This unique geological feature offers a wealth of experiences for divers of all levels, making it an ideal location for adventure seekers.

Diving at Kilsby Sinkhole

Kilsby Cave, classified as a sinkhole dive, is theoretically the easiest level for divers and is mostly used for beginner dives. It’s easily accessible thanks to its open cabin area. Reports indicate that about 1,000 dives are conducted at the sinkhole every year, making it a popular diving location.

For the past 40 years, the sinkhole has offered clear water and allowed divers to descend up to 131 feet below the surface, adding to its allure. However, the sinkhole also has many twists and turns, making it notoriously dangerous. One of the biggest risks is that someone or something could end up anywhere within the system, making the recovery process quite lengthy.

Despite these risks, divers continue to be drawn to the Kilsby Sinkhole thanks to its unique geological features and exciting diving experiences. The 18-year-olds Brett and Patrick were relatively new to diving when they decided to venture down to Mount Gambier with a group of friends, including George and Carrie, to engage in some pleasurable diving.

While George had previously gone diving with Brad and Pat in the sinkhole, the day before, he had to surface early due to ear problems. Despite George’s setback, the group was still eager to continue their diving adventure. They had made a successful dive to 180 feet after an exhilarating experience.

Incident 1: Brett and Patrick’s Dive

On April 6, 1969, a group of 10 individuals arrived at the sinkhole, consisting of three scuba divers or snorkelers and three non-diving friends. Four of the group members intended to engage in snorkeling around the cave, while Brett, Pat, and George were set to undertake a deep dive, with George taking photographs near the surface. George warned the others about not diving too deep due to their lack of experience and essential equipment.

However, despite the warning, the group felt confident enough to engage in the deep dive, as they had completed a similar dive the previous day. They also expressed the unwise intention of wanting to scratch their names on the cave’s wall, located at a depth of approximately 196 feet. This objective was especially reckless given their lack of experience, overweight condition, and absence of essential equipment required for the dive.

After taking some photos on the surface, the group began their descent. Brett and Pat secured their end of the safety line to a large boulder at a depth of approximately 91 feet. They then moved horizontally into the extensive cave located to the southwest of the entrance lake. Shortly after, the safety line became tight, and the surface end was released so they could pull it in behind them.

George intended to follow the safety line down, but he faced an issue as he tried to tie his camera to the rope ladder. The safety line had vanished by then. After descending to a depth of roughly 98 feet, he discovered their line fastened to a boulder but didn’t spot any sign of his companions in the dark and murky cavern beyond. George decided to wait for a few minutes, but his companions failed to return even after five minutes had elapsed. He ascended to the surface and discussed his concerns with Carrie, which led to his decision to dive again for as long as he could.

As George descended again, he activated his backup air supply. He arrived at the tie-off boulder and examined the line once more, but there was no sign of movement in the dark, clear water. Realizing that time was running out and he was low on air, he resolved to return to the surface. However, he saw something gleaming in the corner of his eye approximately 32 feet to the left of the main line in the chamber.

As he swam closer, George recognized it as a torch and hoped to find his diving companions safe and sound. To his dismay, he discovered one of his fellow divers lying lifelessly on his back, and a few meters away lay the second diver motionless. Overwhelmed with shock and disbelief, George knew he had to act fast. Swimming back to the surface, he quickly informed the others of the tragic turn of events.

Devastated by the loss of their fellow divers, the group knew they had to do something to help. Far from any assistance, their only option was to exit the hole and seek help. It took a skilled diver with approximately six years of experience, along with the help of others, three hours to recover the lifeless bodies of Pat and Brett.

Despite the long wait, the victims’ torches were still glowing, and their equipment provided clues about their final moments. The postmortem examination revealed that death was the result of air embolism due to decompression, and the doctor also mentioned drowning and vasovagal inhibition. The tragedy underscored the importance of proper training and adherence to safe diving practices.

Incident 2: Dr. Robert McAllister’s Dive

In another incident on March 13, 2010, Dr. Robert McAllister, a 52-year-old proficient diver and health professional, went on a dive in the Kilsby Sinkhole with his friend. Dr. McAllister followed strict safety protocols and maintained his equipment meticulously. During the dive, he encountered distress, and his friend attempted to help him. However, a struggle ensued, and Dr. McAllister removed his mask and mouthpiece, making it impossible for them to engage in the necessary techniques.

Realizing the severity of the situation, his friend promptly alerted the emergency services and provided care for shock. The recovery team eventually discovered Dr. McAllister’s body entangled in the cave’s guide ropes.

Conflicting reports exist regarding the cause of Dr. McAllister’s death, whether it was due to being entangled in the guide ropes or if his friend attempted to assist him in freeing himself. The circumstances surrounding his passing remain unclear, but it serves as a reminder of the potential dangers inherent in diving and the need for caution and proper training.

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Where is the Kilsby Sinkhole located?

The Kilsby Sinkhole is located in South Australia, near Mount Gambier.

Who were the divers involved in the incidents at Kilsby Sinkhole?

In the first incident, the divers’ names were Brett, Patrick, George, Carrie, and Dr. Robert McAllister.

What is the level of difficulty at Kilsby Sinkhole?

Kilsby Sinkhole is classified as a sinkhole dive and is considered the easiest level for divers, often used for beginners.

How many dives are conducted at the sinkhole every year?

Approximately 1,000 dives are conducted at the Kilsby Sinkhole each year.

What were the causes of the incidents at Kilsby Sinkhole?

In the first incident, the divers encountered issues with the safety line, resulting in the loss of two divers. In the second incident, the cause of Dr. McAllister’s death remains unclear, with conflicting reports suggesting entanglement in guide ropes or complications during a rescue attempt.

Patrick Broin
Patrik, a seasoned cave diver, shares his first-hand experiences and expert insights on the treacherous world of cave diving accidents.
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