Underwater Cave Expedition Turns Deadly: The Mysterious Tragedy of Tytoona’s Sump 2

Underwater Cave Expedition Turns Deadly: The Mysterious Tragedy of Tytoona’s Sump 2
Incident LocationDiver Names
USA, Pennsylvania’s Blair County, Tytoona CaveJohn Schwein, Roberta Schweisgood

Two NSS certified cave divers went on an exploratory dive at the Tytoona Cave to carry out a series of survey dives. They took turns solo diving due to the silty condition of the cave. However, an entanglement occurred in the survey line that threatened the life of Roberta Schweisgood.

Deep within the water, Tytoona Cave Preserve owned by The National Speleological Society is situated in Pennsylvania’s Limestone Rich Sinking Valley in Blair County. Even though Sinking Valley is home to several other caverns, only Tytoona and the Arch Spring are particularly notable.

By Road, Arch Spring is about one mile from Tytoona Cave’s entrance. It passes through a huge chunk of slanted limestone that has carved out a very distinctive entrance in the ground. The width of the cave is entirely made of dry earth when everything is dry. However, water will soon rise from the earth and cover a large portion of the cave in a not-too-deep stream. The entrance’s roof is around 40 feet broad and up to 12 feet high, and it slopes with the huge Trenton Limestone beds’ 15-degree dip.

The trunk tunnel, which runs from the entrance to the sump, is usually 30 feet wide and 25 feet high with a few mild events. Except for the clay banks beside the stream, which occasionally take up the majority of the passageway width, the ground is mostly level. Near the back are a few deep pools. The Tytoona Cave Nature Preserve has laws that must be obeyed, including not leaving any indication of your presence. Although some of the cave is accessible for free self-guided exploration from 6 am to 9 pm, although this cave is very simple to explore, there are still significant risks, so you should enter at your own risk.

The Dive Plan

John Schwein and Roberta Schweisgood, two NSS certified cave divers, prepared to do several survey dives at Arch Spring, close to Altoona, Pennsylvania. John, a well-known cave diver and explorer, had dived in many caves. Roberta was also a very experienced cave diver, and she was dedicated to her cause. To her friends, she was never too busy to give advice on gear and techniques or to talk about the best places in the cave to discover new passageways.

On June 18, 1988, Roberta joined the expedition after John and NSS diver Jim Brown had been exploring this area for the previous four years. Their goal was to connect Arch Spring with Tytoona Cave’s Sinking Stream, which is situated about 4,000 feet to the southwest. The current length of Arch Spring is 2,250 feet and it includes a 250-foot initial sump, or sump one, which can be as deep as 35 feet, and an 850-foot canal or air bell that leads to sump two.

Conditions and Challenges

This last sump is 1,000 feet long and falls 300 feet to a depth of 70 feet near the termination of the line. The route descends to a depth of 105 feet before rising 25 feet into a terminal chamber 200 feet away from sump four in Tytoona Cave. John had already endeavored to get through the breakdown at the end of this chamber, which is where the alleged connection to Tytoona is located. The water in both caverns was about 51 degrees Fahrenheit, and visibility was at most two to three feet.

Zero visibility conditions are expected to persist throughout the dive’s exit because of the significant silt deposits on the tunnel walls and floor, as well as its relatively slow flow. Although there are smaller parts, the potential for line traps exists in various places, especially in some too where the rock is more fractured than in some one. The average passage size in Arch Spring is around six to eight feet in width and height. A second survey of our Spring’s most remote area was conducted on June 18th to determine its exact location to Tytoona.

Mapping the Unknown: Surveying the Treacherous Passages

John dove in the sumptu in Art Spring at around 1pm, and he then made a moderate dye for a penetration of 700 feet along the current line. A rock in the final chamber’s middle is where he tied off a new number 18 nylon line and reeled it out 190 feet to two branch lines that run a small distance to various spots in the breakdown. At this point, he clipped the reel to the line and recorded the places along it where there were large Azimuth deviations.

Azimuth is the true bearing of a survey line determined by measurement from an accurate survey. The moment he exited, Roberta was standing at the entrance to sump 2. They had intended to do a series of solo dives. Due to the silt out circumstances, Roberta’s main task was to remove the number 18 line and take Azimuth and depth measurements along the line that John had just laid. John exited the cave at 2:50 while she went into sump 2.

John became worried at 6:15 PM when Roberta didn’t arrive back at the parking lot. He re-equipped at 8:15 PM and dove some 1 to check the canal leading to sump 2 in the hopes that Roberta had been held back there because of mechanical issues. This was after he had taken a trip into town for backup light batteries. Unfortunately, she was not in the Airfield too. After exiting with a heavy heart, John drove to the Huntington State Police barracks and started an NCRC rescue call down from there.

On June 18th at midnight, Bill Stone in Maryland got a call asking for help rescuing Roberta. John was summoned to the state police station, and the specific requirements for the rescue squad were discussed in case Roberta had completed the connection and was experiencing technical difficulties. At that time, John had managed to recharge his dive equipment and was preparing to dive to Tytoona Cave’s final chamber with the help of nearby cavers.

Bill got in touch with Rob Parker and Tom Morris in North Florida, as well as John Zumrick, who was also a resident of Maryland. Warren Hall, a former eastern regional coordinator for the NCRC, spoke with Bill and arranged for Tom and Rob to be flown from Gainesville, Florida to Altoona, Pennsylvania, while they awaited the result of John’s Recon dive in Tytoona. John called Stone at 5am on June 19th to let him know that he had not located Roberta and that the dive team needed to get ready.

Mobilizing the Rescue: Coordinating a Multi-Team Effort

On June 19th, the team arrived at Arch Spring at about 2 p.m. Local NCRC coordinator Jacques Grief had organized a significant quantity of surface support, including a mobile 20 cubic foot per minute 5000 psi compressor. Rob and Tom entered Arch Spring late on Sunday, June 19th, and made it to sump 2, where they penetrated for around 690 feet, not far from where John had connected the new number 18 line. They were certain Roberta was past that point because they had spent the majority of their time meticulously combing the passageway with an average visibility of one foot. There was still a chance that she had found an air bill and that additional exploration would uncover a line leading up to it.

On Monday morning, June 20th, a solution was found when John found Roberta barely 10 feet beyond the spot where the new line had been tied off. She looked to be trapped in a low area on the south side of the passageway just past a brief restriction and was looking into the cave. A few hours later, Rob and Tom arrived at the same spot and confirmed that both pressure gauges were showing zero. Rob said that he’d have to put a lot of effort to free Roberta from the restriction and get her ready for a safe ride. At this point, it was decided to construct three transport teams by adding a sixth diver, Jim Brown.

Due to the poor visibility and tight circumstances in sump 2, Jim was flown from North Carolina, where he had been on holiday, to Altoona. Since he and John knew the cave the best, the operation wasn’t finished by the six divers until Wednesday night, June 22nd. Two-man teams would be deployed, and this decision was agreed upon for the safety of the rescue team. Roberta’s transportation was the responsibility of one person, and the second’s job was to keep a positive connection on the line six feet in front of the first. The two divers were connected by a six-foot cable that had carabiners on both ends.

In this way, the other diver could deal with the obstacles without being concerned about losing the line. Three divers were only required for the journey through sump 1, where the passage includes numerous line traps. Behind Roberta, a third diver was required so the control would be accessible at both ends of the complex tunnel. This maneuver was easily executed in one dive by Rob, Tom, and Bill. The majority of the recovery operation was done in low visibility, less than one foot.

Roberta’s tools were examined, and no mechanical issues were discovered. With brand new 95 cubic foot steel tanks, she had been diving twin cave valves, as had every member of the rescue team apart from Zumrick, who utilized a standard dual valve manifold. Before going into sump 2, Roberta told John that she had 3,000 PSI in one tank and 2,700 PSI in the other, giving her significantly more air than 190 cubic feet. She also mentioned that she had rectified a little free flow due to the first sump in her new USD regulator when connected to recently charged tanks. Both regulators worked well.

The objective was to survey and then recover the reel. However, Swicegood’s dive slate was ruled out for survey and had only one depth and Azimuth value, suggesting that the survey had been abandoned for some reason. Her tool bag was devoid of a compass. On July 2nd, John discovered it near the spot in the final chamber where he had tied off the survey reel. Additionally, according to Parker, the number 18 line was rigid and practically straight up from its anchor point.

Right before the confinement where Roberta was, he observed a loose portion of line 18 just beyond it, dangling vertically till it reached the ground and then disappearing up the silt slope that continued beyond there. From there, the channel ascends, reaching a depth of 50 feet before abruptly plunging into the 105-foot dip in the final chamber, which is located another 115 feet away. The number 18 line’s tension descent and loose descent higher upstream suggested that there was a problem or possibly a tie-off close to the roof.

Unanswered Questions: Examining the Mysteries Surrounding Roberta’s Fate

Roberta’s fate is unknown. However, based on the information gathered, the following accident scenario seems likely: At the beginning of sump 2, Roberta passed John, and the two swapped notes and talked about the dive before Roberta continued to a depth of 700 feet, where the new number 18 line started. She then started the survey, but she stopped it after just one shot. Since the compass was later discovered in the last chamber, it’s obvious that she decided to stop for some reason. Her dry suit most certainly tore as she passed the restriction before the survey line tie-off. According to John, there are sharp projections in this location that might readily catch a dry suit.

The survey reel would be required when John and Roberta dive into Tytoona Cave later that day, so maybe this was why Roberta probably decided at that time to proceed to the final chamber and retrieve the reel before leaving. Despite the dry suit tear, when she got to the last compartment, she took up John’s reel and dropped the compass unknowingly. She began by reeling back the line in a space with visibility probably less than one foot. Unfortunately, she got tangled up in the number 18 survey line when reeling it in somewhere between the 55-foot level and the restriction at 70 feet.

This was unlikely to happen if she had the survey line ahead of her while she was reeling it in, but it was feasible if, for certain reasons, she had turned around and the survey line was just behind or to the side of her. She would then have to cut the survey line, not since it was so tough. She appeared to have spent almost all of her air while searching for the line.

She may have fallen asleep there after losing consciousness. Even though she was discovered on top of the line leading into the cave, if she had discovered a line, she would not have traveled more than 50 to 70 meters before recognizing and advising she was heading in the wrong direction. Unfortunately, a brave diver met her Waterloo while doing what she was most passionate about at the age of 35.


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Where is Tytoona Cave located?

Tytoona Cave is located in Pennsylvania’s Limestone Rich Sinking Valley in Blair County.

What were the divers’ goals during the dive?

The divers’ goal was to connect Arch Spring with Tytoona Cave’s Sinking Stream.

What were the conditions and challenges faced during the dive?

The water temperature in both caverns was around 51 degrees Fahrenheit, and visibility was limited to two to three feet. The cave had silt deposits, resulting in zero visibility conditions in certain areas. The divers also had to navigate through narrow passages and deal with potential line traps.

How was the rescue operation organized?

A multi-team effort was coordinated, involving six divers and significant surface support. The rescue teams used a transport system, with two-man teams connected by a cable and carabiners to maintain a positive connection to the guide line.

What happened to Roberta Schweisgood?

Roberta’s fate remains unknown. It is believed that she became entangled in the survey line while attempting to retrieve the reel in low visibility conditions. She likely ran out of air while searching for the line and may have lost consciousness.

Rebecca Penrose
Rebecca, an experienced blogger, delves into the world of diving accidents, sharing insights, stories, and valuable lessons learned. Dive in and explore the depths of underwater safety.
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