Carpenter : In the near term, and maybe for an extended term, deep-sea exploration is much more important. In the long term, space is the last frontier. But in the near term, the ocean needs better attention and a clearer understanding. And that’s what we are trying to achieve. It used to be that deep-sea exploration was primarily a defense-oriented project. In a way, it’s still defense-oriented; but we’re trying to defend the planet now, instead of just this country.

Naval History : How important is public appreciation of what SeaLab accomplished, even though we’re not doing the same things anymore?

Carpenter : Right. We’re not doing it anymore. And I can’t tell you how important it is. But I do feel comfortable saying it’s more important than we realize. I have such an unbounded respect for the value of new knowledge, new truths. And that’s what we’re still trying to do, at all levels. I think it’s vitally important for our ultimate survival.

Naval History : So you think deep-sea exploration is more important than the International Space Station, for instance?

Carpenter : I’ve always objected to having the two modes of exploration appear as competitive. I think they are complementary. And we’re learning, from all of these experiments, more about where we are and who we are and where we’re going. That sounds highfalutin, but it is all in an attempt to gain new knowledge, which is our salvation.

Naval History : Explain, if you would, the function of the SeaLab program.

Carpenter : In order to understand the ocean and the sea floor and life in the ocean, you have to spend time there. The deeper you go, the harder it is to spend time because of the diver’s albatross, which is decompression. The goal was to provide a pressurized habitat on the ocean floor for a deep-sea diver—one where he could enter the water freely, work as long as possible, and come back and eat and get warm and sleep without paying the decompression penalty. That’s a major advance in our ability to gain new knowledge from the ocean floor. And that’s what SeaLab was.

It was postulated by [Captain] George Bond [U.S. Navy (Retired)], who was behind all of the early work done by Jacques Yves Cousteau, which drew interest from the United States. It came from U.S. Navy work at the hands of George Bond. [See Captain Bond’s book, Papa Topside (Annapolis, MD: Naval Institute Press, 1993).] It just says that if a man in a high-pressure environment is in equilibrium with the pressure of the water outside, the longer he stays at that depth, the longer he must decompress—up to 24 hours, when his blood becomes saturated with the breathing atmosphere mix. After 24 hours, he can stay for 24 weeks and still need only the same decompression time. So it makes divers much more efficient in water. And that’s what SeaLab proved.

Naval History : So SeaLab was more for diver efficiency than, perhaps, colonizing the ocean floor at some point?

Carpenter : Well, one leads to the other. I don’t really see a need, at this time, for residential communities on the ocean floor; maybe one day industrial communities, but that’s a long way down the road. But increased freedom in the deep ocean is valuable right now, and that’s what we developed in SeaLab.

Naval History : In hindsight, how do you think SeaLab would be today, if it had been sustained, rather than canceled?

Carpenter : We would have discovered the same things we have discovered in the chambers of the experimental diving unit. We’ve run up against a brick wall because of this physiological limit of 2,000 feet. We can’t really live and work at depths greater than 2,000 feet. And it’s not clearly understood why.

You know, in the SeaLab II film, the narrator makes a statement something like—I’ll paraphrase—”who knows, perhaps in some years we will be diving out of a sea lab at 20,000 feet.” We all thought we were on an open-ended experiment that would go deeper and deeper as soon as we built the technology. We didn’t know at that time that we had a physiological limit at 2,000 feet. So we’re locked out of deeper water until the medics can figure out how to handle that.

Naval History : In light of the USS Greeneville (SSN-772) accident, how
important are visits to Navy ships and submarines to the Navy?

Carpenter : I think they are important, and I don’t think we should do without them. We can, but I don’t think we should. In light of the Greeneville episode, they must be more carefully monitored. I think we might have to be more selective about what we do while there are civilians on board; or maybe just monitor the whole thing more closely. That was human failure spread out all along the line. The whole thing, I think, needs to be reevaluated, but not discontinued.

Naval History : Which were you more interested in—flying or going deep?

Carpenter : My first interest was flying. I was inspired by the very popular war [World War II]. But that led to a fascination for the ocean, mainly because when I started flying for the Navy, I was in Hawaii and got acquainted with the coral reef, skin diving, and spear fishing. And I’d read everything that Cousteau had written and seen all he had produced on film. That was my second love. I am still fascinated by the underwater world. It has a fascination for me of a type that the atmosphere and space do not. But they’re both addictive.