A team of British divers have dived the terminal sump of Hang Son Doong with support from Oxalis recently. In extremely challenging conditions, the sump was dived to a depth of -77m making it the deepest cave dive in Vietnam.
Son Doong Cave is located in the heart of the Phong Nha Ke Bang National Park in Quang Binh province of Central Vietnam. Only recently explored in 2009-2010 by the British Cave Research Association, Son Doong Cave has only been open to the public since 2013. All research and tourist expeditions have thus far have been organized and led by local adventure tour company Oxalis, in partnership with British Cave Research Association and with the permission of the government of Vietnam.
The discovery was announced following a research diving trip made by a team including the heroic British divers Richard Stanton, John Volanthen, Jason Mallison and Chris Jewell, who were members of the rescue team saving the Thai football team trapped in Thailand’s Tham Luang Cave last year.
The research commenced this month and the divers started work at the end of the river inside Son Doong and went further into a water passage. The research was expected to prove that the passage connected Son Doong and the Thung Cave, which is a cave of the same type laying 600m away.
Unfortunately, normal air compressors that the divers had during the research trip were unable to keep them safe for further diving and the divers had to end their first visit to the tunnel.
However, according to Howard Limbert, Mallison’s remarks helped prove that Son Doong did not end where the river poured into the passage, but expanded into the underground tunnel. Limbert was a member of the British caving team who first explored the cave. Today he is the technical manager of Oxalis Adventure Tours, the sole tour provider into the giant cave.
Howard appraised the early success in finding the tunnel and described the diving as one of the most “difficult and challenging tasks”. Oxalis put up US$53,000 and organised the research expedition. The national flag carrier Vietnam Airlines offers the heroic divers free two-way flights from the UK to Vietnam.
(Infographics) Son Doong cave remains a mystery