National Geographic


Ron Allum

Photograph by Randy Larcombe

Submersible Co-designer and Pilot

Ron Allum has been heavily involved in James Cameron’s deep-sea expeditions since 2001. During this time his quiet manner and unique ability to adapt, design, and build special equipment for use on the Russian Mir submersibles earned him the title of “The Professor” aboard ship.

For Cameron’s 2004 expedition to the Atlantic and Pacific deep-ocean vents, Allum designed and built new pan-and-tilt systems for the 19,685-foot (6,000-meter) 3-D high-definition rig used on both Mir submersibles and on Cameron’s Deep Rover submersibles. In 2005, he designed and built a broadcast system enabling the Mir submersibles to beam a live broadcast from Titanic from 12 cameras on the ocean floor via a 19,685-foot (6,000-meter) fiber-optic spool system link to the surface.

He commenced work on the DEEPSEA CHALLENGER submersible in 2005, researching and overseeing the building of the pressure sphere that forms its core. When the sphere was completed he went on to develop a unique formula for syntactic foam capable of withstanding the extreme pressure of full ocean depth. That foam provides the flotation and forms the structural chassis of the DEEPSEA CHALLENGER. Allum’s unique, pressure-balanced, oil-filled electronic systems and other innovative ideas have kept the submersible’s weight to a minimum while maximizing its ability to do science and imaging work in the world’s deepest spots.

In addition to his technical skills, Allum is regarded as one of the world’s most experienced and accomplished cave divers. His fondest memory is of leading a 1983 expedition to Cocklebiddy Cave on Australia’s Nullarbor Plain, where the expedition achieved a world record push of 3.88 miles (6.24 kilometers) into the cave system. Allum is married to author Yvette Allum. They have two daughters, Madelaine, 12, and Sophie, 11.

Science Partners

  • Additional major support provided by The Alfred P. Sloan Foundation
  • NASA Jet Propulsion Laboratory
  • Scripps Institution of Oceanography, UC San Diego
  • University of Hawaii at Manoa
  • University of Guam