New Underwater Threshold Of The 1980S, Demands New Answers From Underwater Contractors

ABSTRACT This discussion analyzes present and projected trends in underwater contracting, as related to exploratory drilling in constantly deeper waters in the quest for new fossile fuel sources. Its primary focus is on the problems facing diving contractors who must be careful in their efforts to survive and prosper in an industry that is expanding in all directions underwater, while new sub-sea technology has tended, as of late, to remain moot. Three basic modes of underwater diving service - hyperbaric; monobaric; and remote control - are examined. Specifically, this analysis is aimed at the problems associated with supporting exploratory drilling in waters beyond 1500 feet deep, the depth at which anchors have to be abandoned in favor of dynamically positioned vessels. A threshold has been reached comparable to the 200 foot watershed met in the early 1960s, which was overcome by the introduction of mixed gas bounce dives to 600 feet for short term projects, and saturation diving practices which are today used on long term projects to depths of over 1000 feet. Vital work beyond 1200 to 1500 feet, the author contends, will have to be carried out either by tethered unmanned vehicles compatibly designed to work on deep sea structures; by manned monobaric diving suits or bells; or more likely, by free swimming submersibles. An analysis of present methods of under water intervention is given, followed by an explanation of the role free swimming submersibles will probably play in the future as an adjunct to deep sea drilling techniques. It concludes that manned submersibles will in effect be safer, with far greater operational capabilities, than either monobaric diving suits or tethered unmanned vehicles. It also notes that the problems of safety in deep water offshore operations may be the determining factor in resolving which options will be selected by oil companies, as governments, under whose jurisdiction they operate, move to ensure that diving accidents are kept to a minimum. HISTORY Two decades ago man's ingress into the underwater environment, although centuries old, was still in its infancy. Working dives to depths beyond 200 feet were rare and carried out commercially only on compressed air, mixed gas still being the domain of the united States Navy. Despite the fact the deepest known depths of the oceans had been plumbed by the bathyscaphe Trieste, mid and shallow water submersibles were just beginning to appear and none were being built for commercial application. When in 1961 a young Swiss mathematician, Hannes Keller, irrefutably demonstrated by going to a 1000 feet (in a hyperbaric chamber) that the depth barrier for man breathing an artificial atmosphere was far beyond what many experts deemed the absolute limit, there were still those who claimed manned intervention to such depths would never be practical, nor would there be justifiable application.