Table 2. Research Studies Conducted in 330-Meter Simulated Saturation Dive, September 1990 1. Study of High Pressure Nervous Syndrome Using Electroencephalographic (EEG) Topography and Vestibular Function Testing. 2. Use of the Duke-GKSS Linear Decompression Method During Current UMC Saturation Dive. 3. Use of M-Mode Echocardiographic Methods for Intracardiac Bubble Detection. 4. Study of Red Blood Cell Production Under High Oxygen Partial Pressure Environment. 5. Work Capacity of Divers in a High Pressure Environment. 6. Monitoring of Vital Signs and Body Heat Loss During a Saturation Excursion Dive. 7. Ventilatory Dynamics Under a High Pressure Environment. 8. Control of Carbon Monoxide in DDC During a Deep Saturation Dive. 9. Improvement of Electronic Voice Receiver Characteristics in Underwater Breathing Apparatuses. 10. Function Testing of Tear Secreting Glands in a High Pressure Environment. 11. Testing of Taste Sensation in a High Pressure Environment. 12. Standardization of Emergency Procedures for Decompression Sickness in a Saturation Diving Setting. 13. Adjunctive Therapy for Decompression Sickness During Saturation Diving. The total annual budget for UMC is approximately $2 million, excluding salaries, with $140,000 set aside for research. Other major areas of research besides saturation diving include development of a new decompression schedule for the semi-closed circuit underwater breathing apparatus used by JMSDF EOD divers with the aid of personal computerized diving recorders, development of air saturation decompression tables for use during rescue of crewmembers from a sunk submarine with a pressurized environment, and continued investigation into the physiological and psychological effects of the sealed submarine environment on personnel with an emphasis on atmosphere control and efficient work-rest cycles. Although a relative newcomer to the field of undersea medicine, UMC has steadily grown into a world-class undersea research center based on the strength of its facilities, in particular the DDS. During the last Undersea and Hyperbaric Medicine Society international meeting, UMC scientists were responsible for several presentations. Future successes will depend more on the capabilities of its research personnel. In this area, UMC is committed to having more investigators through addition of staff as noted above and increasing access to outside scientists. Beginning in 1993, NDMC will have an affiliated basic medical research institute. Personnel from this institution will be highly encouraged to use equipment at UMC to conduct experimental studies. Strong relations with the Science University of Tokyo, which has senior computer science students develop software for certain UMC projects, and the Department of Hygiene, Saitama Medical College will also be continued. Efforts are now underway to establish formal ties with foreign institutions such as Duke University in Durham, North Carolina; the Naval Medical Research Institute in Bethesda, Maryland; and GKSS in Germany. CONCLUSION UMC is an internationally respected undersea research center. Its facilities and equipment are some of the most up to date in the world. In the past, it has not always had the number of researchers one would expect an institution of its capability to have on staff. However, efforts are being made to change this situation, which should give UMC the ability to develop leading edge technologies in regards to saturation diving. Neal Naito is a resident in internal medicine at Naval Hospital Oakland. He was previously stationed at Submarine Group Seven in Yokosuka, Japan, as an undersea medical officer. After graduating from the University of California at Davis with a B.S. in environmental toxicology, he attended the Uniformed Services University of the Health Sciences where he obtained his M.D. in 1986. He then did an internship in internal medicine at Naval Hospital Oakland prior to receiving training as an undersea medical officer at the Naval Undersea Medical Institute in Groton, Connecticut. Kenneth C. Earhart, a lieutenant in the U.S. Navy Medical Corps, has been assigned to Submarine Group 7, Yokosuka, Japan, since January 1990. He practices submarine and diving medicine, both in Japan and throughout the Pacific. Dr. Earhart received a B.S. degree from Michigan State University, East Lansing, in 1983.. From 1982-83 he was an exchange student at Konan University in Kobe, Japan. In 1988 Dr. Earhart received his M.D. from Wayne State University in Detroit. In 1989 he completed an internship at Bethesda Naval Hospital and also attended the Undersea Medical Officer School at Groton, Connecticut. Cameron A. Gillespie is the head of the ENT Department at U.S. Naval Hospital Yokosuka, Japan. He obtained a B.A. in psychology in 1970 and an M.D. in 1974 from the University of Virginia. He did a residency in ENT surgery at Naval Hospital Oakland between 1976-79 and a Head and Neck Surgery Fellowship at Duke University Hospital in 1984. He has attended both NOAA and U.S. Navy sponsored hyperbaric and diving courses. A VISIT TO THE JAPAN MARITIME The Chiyoda is a multipurpose submarine rescue and saturation-divingcapable ship belonging to the Japan Maritime Self-Defense Force (JMSDF). Built in 1985, it serves as the mother ship for the sole deep submergence rescue vessel (DSRV) in JMSDF. Recently, the authors were invited aboard the Chiyoda to observe a DSRV-submarine rescue exercise. This article reports on that visit in view of recent interest in the area of rescue of personnel from disabled civilian scientific research submersibles. INTRODUCTION With a large fleet of modern, dieselelectric submarines, the Japan Maritime Self-Defense Force (JMSDF) also needed the parallel capability to rescue crewmembers from a disabled submarine. Thus in 1985, JMSDF commissioned the submarine rescue ship Chiyoda (AS-405). Built by Mitsui Heavy Industries, the Chiyoda carries a deep submergence rescue vessel (DSRV), a 300-meter saturation diving system, and a remotely operated vehicle (ROV). Information on the precise maximum depth of the DSRV was not available. While owned by the military, the Chiyoda also serves a valuable role to the Japanese civilian undersea research community as an available resource for manned submersible rescue. Just in this past year, the first international conference on submersible rescue was held in Woods Hole, Massachusetts. Cosponsored by the Woods Hole Oceanographic Institution and the Japan Marine Science and Technology Center, the 2-day forum included representatives from the Soviet Union, France, and Canada. That this conference was held underscores the growing interest in this problem among civilian ocean research organizations. by Neal A. Naito and Robert T. Appleby By contrast, the military submarine THE Chiyoda Recently, the authors were invited The Chiyoda is 113 meters long, 17.6 meters wide, and has a draft of 4.6 meters. It weighs 4,450 tons fully outfitted and has a top speed of 15 knots. At a speed of 13 knots, the Chiyoda has a cruising range of 6000 miles. Its propulsion system consists of two variable pitch screws and four through the hull side thrusters. Two thrusters are located aft and two forward. The screws are powered by two 6,000-hp engines, which can be disengaged and clutched into two 1,000-kW and two 850-kW electrical generators that run the thrusters. There are also three service support diesel generators for general electrical needs. The amount of force delivered by the thrusters is controlled by varying the angle of the propellers, which can be turned through an 180° arc. The side thrusters are the key to the Chiyoda's dynamic positioning system (DPS), which allows it to make a 360° turn around a single axis or to maintain a stable position without anchoring. In comparison, the U.S. Navy's most modern submarine rescue ship does not have side thrusters and uses a four point mooring system with a depth limit of 1,000 feet. In water over 1,000 feet deep, position cannot be |