The Submersible Synopses: NR-1


NR-1 is the navy’s smallest nuclear-powered and only nuclear-powered research submarine. Launched in 1969, th 145′ NR-1 (known affectionately as Nerwin) was designed for deep submergence work on the seabed ranging from recovery, repair, implantation, and observation. Given its nuclear reactor, missions on the bottom can last day limited only by consumables. The submersible possesses bunks for these extended missions. Despite this independence, it generally towed and does not stray far from a surface support ship, currently the MV Carolyn Chouest.


During extended missions, NR-1 typically has a compliment of 13 (2 officers, 8 enlisted, and 2 scientists). I believe the crew compartment is composed of 3 steel (titanium?) spheres connected together. Three 4-inch view-ports on its bottom, nineteen 250-watt gas discharge lights, eight 1000-watt, two 500-watt incandescent lights, and 16 different low light TV cameras in various locations allow multiple opportunities for observation. One key feature that makes Nerwin cooler than other than any other research submersibles is the presence of a periscope (and lets not forget that nuclear reactor!). The hydraulic manipulator arm can lift objects weight up to a ton.


NR-1 has conducted many underwater searches, underwater repair and salvage operations, including the recovery of critical wreckage from an Air Force F-14 lost off the coast of North Carolina, EgyptAir Flight 990 off the coast of New England, the Challenger shuttle in 1986, and the discovery of the USS O-12 (SS-73) and 25 other shipwrecks in a 12-hour period in a Norwegian fjord.

As Peter can attest in 2007, NR-1 was used to survey the Flower Garden Banks National Marine Sanctuary and other sites in the Gulf of Mexico.

More pictures here.

Dr. M (1729 Posts)

Craig McClain is the Assistant Director of Science for the National Evolutionary Synthesis Center, a National Science Foundation supported initiative. He has conducted deep-sea research for 20 years and published over 50 papers in the area. He has participated in and led dozens of oceanographic expeditions taken him to the Antarctic and the most remote regions of the Pacific and Atlantic. Craig’s research focuses on how energy drives the biology of marine invertebrates from individuals to ecosystems, specifically, seeking to uncover how organisms are adapted to different levels of carbon availability, i.e. food, and how this determines the kinds and number of species in different parts of the oceans. Craig’s research has been featured on National Public Radio, Discovery Channel, Fox News, National Geographic and ABC News. In addition to his scientific research, Craig also advocates the need for scientists to connect with the public and is the founder and chief editor of the acclaimed Deep-Sea News (, a popular ocean-themed blog that has won numerous awards. His writing has been featured in Cosmos, Science Illustrated, American Scientist, Wired, Mental Floss, and the Open Lab: The Best Science Writing on the Web. His forthcoming book, Science of the South (, connects cultural icons of South such as pecan pie with the science behind them.

6 comments on “The Submersible Synopses: NR-1
  1. I’ll also attest the crew can remain submerged for a month thanks to a generous complement of oxygen candles and microwave chicken tenders, and that the NR1 can deploy wheels to drive along the seafloor (but not inside the Sanctuary). No joke, unless its on me. Great series, Craig.

  2. Isn’t this one bound for decommissioning this year?

    How many other manned submersibles are being lost in the next few years?

  3. Is WHOI planning a replacement?
    Brad Seibel recently mentioned that the Johnson Sea Link would be going offline soon too. I don’t recall is he mentioned which one or if it would be both of them. I understand that HBOI is not planning any replacement for the JSL’s.

  4. Alvin will be replaced with a deeper diving model with more portholes. The titanium sphere is already built. The JSLs are in dry storage, as I understand it. Apparently, they were not part of the package when HBOI was purchased by the State of Florida, to be absorbed into Florida Atlantic University.

Comments are closed.