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La Chalupa habitat in port; aquanauts Frank Torres, (PRINUL staff), me and John Montgomery
The Puerto Rico Inter-National Undersea Laboratory project created the most elaborate of the underwater habitats in its time, La Chalupa, with living and working space for four aquanauts. It was mobile, so that it could be taken to a different location for each mission and settled to the bottom on four adjustable legs, connected to a boat bouy at the surface with power generator and compressor to maintain the habitat at bottom pressure. There were two large cylinders, one for decompression at the bottom, and the other for decompression at the surface, with a space for diving gear in between open to the water, so divers could go in and out. One cylinder for sleeping had four bunk waterbeds and some work space, the other included the kitchen with microwave oven and freezer, and the technical and communications equipment to monitor and maintain the atmosphere in the habitat. There were also two smaller detachable cylinders for emergency evacuation.
In December 1972, I was one of four aquanauts in the second PRINUL mission (along with a technician to repair some equipment) and, after a prior period of training on land, spent two weeks living on the bottom of a coral reef at 20 meters depth 10 kilometers off the coast of Puerto Rico. Since we were saturated at bottom pressure, we could go in and out as often as we liked, changing air bottles as needed, but of course we could not swim up to the surface or we would be dead in 15 minutes. For our research on the coral reef, it was all the difference between taking a one hour tour of a city and going to live there for two weeks. The fish got used to us, and would follow us around in the hope that we would stir up some food. I studied the way seaweeds and colonial animals collaborated to create stable communities on the sandy bottom (see publication). The team spirit was excellent, and since I was always looking for opportunities to teach the Bahá'í Faith, this seemed like the perfect captive audience (remembered 50 years later). After our mission, the habitat was raised and towed back into port, where we decompressed for 24 hours under medical supervision.
Photos by Seppo Kolehmainen and myself
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La Chalupa habitat in port; aquanauts Frank Torres, (PRINUL staff), me and John Montgomery
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La Chalupa with turbid water from a storm; technician Mike Dugan at work; even an underwater habitat needs sweeping
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Aquanauts Seppo Kolehmainen, Frank Torres, John Montgomery, Arthur Dahl; coming in from swimming during training
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Living compartment; porthole so fish could watch us; Seppo Kolehmainen; me in my bunk
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Seppo Kolehmainen taking data; photographing the reef; John Montgomery
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Me cooking in the microwave; serving Christmas dinner
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Celebrating Christmas underwater; me eating dinner in the kitchen
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Me giving Seppo an ear treatment; some of the habitat instrumentation
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Mailman; the diving port between the chambers
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Me decompressing with oxygen; coming off La Chalupa after our mission
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Autographed envelope of mail from La Chalupa; decal on my portable laboratory
To download a much more complete report on our PRINUL Mission #2 by aquanaut Seppo Kolehmainen in pdf, click here.