1963 USS Thresher Investigation: Rickover Testimony

November 25, 2020 11:09 AM - Updated: December 23, 2020 9:26 AM

This week, the Navy released the third set of documents from a previously classified investigation into the April 10, 1963 loss of USS Thresher and its crew of 129 sailors off the coast of New England.

A freedom of information lawsuit from retired Navy Capt. James Bryant, a former Thresher-class submarine commander, compelled the Navy to release the documents on a rolling basis.

The following is the third set of 12 volumes of proceedings of the court of inquiry ordered by the commander of the U.S. Atlantic Fleet. The rest of the documents can be found here.

The latest release contains the testimony of Adm. Hyman Rickover, the first director of Naval Reactors, as part of the inquiry.

From the report

Q. So far there would seem to be no evidence that the reactor plant of THRESHER had any direct causal connection with her loss. Also, this court has found no evidence of any radiological contamination resulting from the loss of THRESHER at sea. Can you tell us what the radiological risk would be considering that she was lost in about 8400 feet of water?

A. Before answering that question, if I may, Mr. President, I would like to say something about the crew. I’m sure that everyone in this room knows how I feel about the men who were on the THRESHER. I, and members of my Group knew many of them personally. We had selected them, trained them, encouraged them. We knew their problems. We can only hope that in giving their lives for their country they have contributed to our greater safety. It is a personal loss to me. l feel for their wives, their children, their fathers and their mothers.

Having said this, I will now reply to your question. This merely is a restatement of what I have previously said in connection with the radiological effects of the THRESHER loss. There is no reason to believe that any radiological problem has been created or will be created by the loss of the THRESHER.

It might be useful to the court to have me put into its record the public statements
I made on April 11th and 12th, 1963, in that regard. These statements were cleared by the United States Atomic Energy Commission. I have not had any evidence or hypothesis that would lead me to change these statements. Let me now quote for the record my public statement of Apri l 11th, 1963:

“The reactors used in United States submarines and surface warship s are designed to minimize potential hazards to the environment, even under the most severe casualty
conditions, such as actual sinking of a ship. First, the reactor core is so designed that it is physically impossible for it to explode like a bomb. Second, the reactor fuel elements are made of materials that are extremely corrosion resistant, even in sea water; thus, in the event of a serious accident, where the reactor is completely submerged in sea water, the fuel elements will remain intact for an indefinite period of time, and the radioactive materials contained in these fuel elements will not be released. Radioactive material could be released from this type of reactor only if the fuel elements were actually to melt, and in addition, the high strength all-welded reactor boundary were to rupture. The reactor’s many protective devices and self-regulating features are designed to prevent automatically any melting of the fuel elements. Flooding of a reactor with sea water furnishes additional cooling for the fuel elements, and so provides added protection against the release of radioactive material.”

On April 12, 1963, I released the following statement:

“Measurements for radioactivity and samples of debris recovered from the scene of the THRESHER has shown no radioactivity. Samples of the ocean bottom which have also been obtained by the Oceanography Ship, ATLANTIS II in the vicinity of the incident have likewise shown no radioactivity. Additional samples will be obtained and measured.”

Since April 12th, there have been a number of other tests and samples conducted
and in the latest one of which I am informed as of yesterday afternoon, we have
found no evidence of radioactivity.

(Rickover’s testimony begins on page 165 of the document).

USNI News has uploaded two versions of the document. One is the original scan of the pages provided by the Navy, the second is a word-searchable document. Processing the searchable document has left some difficult to read pages blank which can be seen in the original version.

Download the original version here.
Download the word-searchable document here.

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