On Friday, 14 May Brigitte Lenoir, 40, failed to return from a dive to 200m off Dahab, using a Megalodon closed-circuit rebreather.
According to reports within the rebreather diving community, Lenoir had ascended to about 147m before problems intervened and she sank without trace. Her body has not been found.
The extensive underwater back-up team included Frenchman Pascal Bernabe, who claimed a record 330m dive off Corsica in 2005.
Lenoir’s fateful dive was intended as a work-up toward an attempt at the depth of 230m in August. She had already completed a dive to 154m at Geneva’s Lake Leman in April, with a 30-strong support team.
Had she completed her 200m dive, Lenoir would have become the deepest diving woman in salt water. In April, Mexican Sofia Ponce carried out a sea dive to 190m, on open circuit.
Lenoir’s ultimate target of 230m was in order to exceed South African Verna Van Schaik’s depth of 221m, achieved on open circuit at the freshwater Boesmansgat cave in 2004.