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Hub AI
Halcyon RB80 AI simulator
(@Halcyon RB80_simulator)
Hub AI
Halcyon RB80 AI simulator
(@Halcyon RB80_simulator)
Halcyon RB80
The Halcyon RB80 is a non-depth-compensated passive addition semi-closed circuit rebreather of similar external dimensions to a standard AL80 scuba cylinder (11-litre, 207-bar aluminium cylinder, 185 mm diameter and about 660 mm long). It was originally developed by Reinhard Buchaly (RB) in 1996 for the cave exploration dives conducted by the European Karst Plain Project (EKPP).
About 1/10 of the respired volume of breathing gas in the circuit is discharged during each breathing cycle by a concentric bellows counterlung system, which reduces the loop volume and is replenished by internal valves, triggered by low loop volume, similar to the function of the demand valve of a scuba regulator.
The Halcyon RB80 was introduced as a replacement for the much bulkier and more mechanically complex PVR-BASC, which was depth-compensated and used a ballasted bellows counterlung.
The RB80 passive addition semi-closed rebreather was originally developed by Reinhard Buchaly (RB) in 1996 for the cave exploration dives conducted by the European Karst Plain Project (EKPP), and is approximately the size of the common 80 cubic foot aluminium scuba cylinder. The Halcyon version of the RB80 was introduced as a replacement for the much bulkier and more mechanically complex Halcyon PVR-BASC, which was depth-compensated and used a ballasted bellows counterlung.
The RB80 has been in use since the 1990s by the Woodville Karst Plain Project for mapping the underwater caves of the Woodville Karst Plain. By 2021, more than 185,000 feet (56,000 m) of cave passage, of which over 115,000 feet (35,000 m) are deeper than 190 feet (58 m). Since 2008, the RB80 has been used by El Centro Investigador del Sistema Acuífero de Quintana Roo (CINDAQ)'s Mexican Cave Exploration Project (MCEP) project for exploration in the caves of the Yucatán. Between January 2018 and December 2020, MCEP divers mapped more than 180,000 metres (590,000 ft) of new cave passage in Sistema Ox Bel Ha using RB80s. The RB80 has also been used for cave exploration projects in China, Australia, the south of France, Spain, Italy, and other karst areas around the world, and has also been used for ghost net removal and for wreck diving.
A modified sidemount version of the RB80, called the RBK has been produced in three versions. It has a smaller scrubber capacity and is shorter, at 50cm, with the same diameter as the RB80. The RBK has been used as a sidemount, travel, and bailout rebreather and has advantages in long-range explorations through small passages.
The RB80 has no electronics or gas monitoring instrumentation beyond a submersible pressure gauge for the supply gas cylinder, and can be left underwater as a stage set with the valves closed and then be turned on and used immediately.
Inhalation closes the mouthpiece exhalation non-return valve and draws gas through the inhalation non-return valve. The pressure drop draws the contents of the outer bellows through the scrubber, inhalation hose, non-return valve and mouthpiece to the diver. As the concentric bellows contract, the pressure in the inner bellows increases and first closes the internal non-return valve, then pushes its contents through the outer non-return valve, discharging to the surroundings. When the bellows is fully contracted, the bottom cover triggers the gas addition valves which inject gas until the diver stops inhaling and the bottom cover no longer presses against the addition valve actuator. If the gas in the breathing circuit has been compressed by an increase in depth, the gas volume will be even less and the addition valves will be triggered for longer, bringing the volume back to the appropriate level. The RB80 uses two addition valves in parallel, so that if one fails, the other will provide the required gas.
Halcyon RB80
The Halcyon RB80 is a non-depth-compensated passive addition semi-closed circuit rebreather of similar external dimensions to a standard AL80 scuba cylinder (11-litre, 207-bar aluminium cylinder, 185 mm diameter and about 660 mm long). It was originally developed by Reinhard Buchaly (RB) in 1996 for the cave exploration dives conducted by the European Karst Plain Project (EKPP).
About 1/10 of the respired volume of breathing gas in the circuit is discharged during each breathing cycle by a concentric bellows counterlung system, which reduces the loop volume and is replenished by internal valves, triggered by low loop volume, similar to the function of the demand valve of a scuba regulator.
The Halcyon RB80 was introduced as a replacement for the much bulkier and more mechanically complex PVR-BASC, which was depth-compensated and used a ballasted bellows counterlung.
The RB80 passive addition semi-closed rebreather was originally developed by Reinhard Buchaly (RB) in 1996 for the cave exploration dives conducted by the European Karst Plain Project (EKPP), and is approximately the size of the common 80 cubic foot aluminium scuba cylinder. The Halcyon version of the RB80 was introduced as a replacement for the much bulkier and more mechanically complex Halcyon PVR-BASC, which was depth-compensated and used a ballasted bellows counterlung.
The RB80 has been in use since the 1990s by the Woodville Karst Plain Project for mapping the underwater caves of the Woodville Karst Plain. By 2021, more than 185,000 feet (56,000 m) of cave passage, of which over 115,000 feet (35,000 m) are deeper than 190 feet (58 m). Since 2008, the RB80 has been used by El Centro Investigador del Sistema Acuífero de Quintana Roo (CINDAQ)'s Mexican Cave Exploration Project (MCEP) project for exploration in the caves of the Yucatán. Between January 2018 and December 2020, MCEP divers mapped more than 180,000 metres (590,000 ft) of new cave passage in Sistema Ox Bel Ha using RB80s. The RB80 has also been used for cave exploration projects in China, Australia, the south of France, Spain, Italy, and other karst areas around the world, and has also been used for ghost net removal and for wreck diving.
A modified sidemount version of the RB80, called the RBK has been produced in three versions. It has a smaller scrubber capacity and is shorter, at 50cm, with the same diameter as the RB80. The RBK has been used as a sidemount, travel, and bailout rebreather and has advantages in long-range explorations through small passages.
The RB80 has no electronics or gas monitoring instrumentation beyond a submersible pressure gauge for the supply gas cylinder, and can be left underwater as a stage set with the valves closed and then be turned on and used immediately.
Inhalation closes the mouthpiece exhalation non-return valve and draws gas through the inhalation non-return valve. The pressure drop draws the contents of the outer bellows through the scrubber, inhalation hose, non-return valve and mouthpiece to the diver. As the concentric bellows contract, the pressure in the inner bellows increases and first closes the internal non-return valve, then pushes its contents through the outer non-return valve, discharging to the surroundings. When the bellows is fully contracted, the bottom cover triggers the gas addition valves which inject gas until the diver stops inhaling and the bottom cover no longer presses against the addition valve actuator. If the gas in the breathing circuit has been compressed by an increase in depth, the gas volume will be even less and the addition valves will be triggered for longer, bringing the volume back to the appropriate level. The RB80 uses two addition valves in parallel, so that if one fails, the other will provide the required gas.