374 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1964 



principles common to both. Speed, endurance when submerged, oper- 

 ating depth, search capability, and weapons effectiveness all have 

 increased by factors imimagined 20 years ago. With these great 

 improvements has come, with much less fanfare, though it is of com- 

 parable significance, an increase in safety of operation. Through 

 all of the second-guessing as to the cause of the loss of this beautiful 

 piece of machinery and its human crew, much has been said of meas- 

 ures which could have been taken to increase its structural integrity 

 or its ability to respond mider conditions of extreme stress, and even 

 of a need to install special emergency data-recording equipment. The 

 remarkable reality, however, and the reason for shock within the 

 submarine forces, is that this loss terminated a 14-year period in 

 w^liich not a single U.S. submarine had been sunk. This is the longest 

 such period since the introduction of these craft into our Navy in 

 1900, with the commissioning of the U.S.S. Holland. There has been 

 a tendency to forget that duty in submarines is considered hazardous 

 in the same sense that duty in military aircraft is. The shock engen- 

 dered by the Thresher accident, in contrast to our acceptance of the 

 loss of more lives in 1963 alone in military aircraft accidents than 

 were lost aboard the Thresher., is a tribute to this new standard of 

 operational safety. 



The purpose of this article is, however, not to recount the various 

 theories as to why this unfortunate event occurred or to discuss the 

 engineering and construction improvements which it has triggered. 

 Rather, we describe the participation of marine scientists and their 

 tools in the search for the wreckage of this ship, which must eventually 

 have found its way to the floor of the sea. Clearly, such a discussion 

 must start with some consideration of why one might want to make 

 such a search at all. There are several answers, each of which was 

 pertinent to a different phase of the operation as it developed. At 

 the very first there was a hope that perhaps the boat had not really 

 gone down but had surfaced in the rough seas and, though crippled, 

 might yet be found, or that some survivors might have escaped. This 

 hope rapidly faded and was replaced by a determination to learn 

 as much as possible for the future from the accident by photography, 

 or perhaps even recovery, of parts of the hulk. Finally, as over- 

 optimistic piecemeal adaptation of techniques showed that the location 

 problem itself was a difficult one and that the craft had been cata- 

 strophically damaged, the emphasis shifted to the long-term problem 

 of developing specialized equipment for careful examination of objects 

 on the sea floor. In this last context the Thresher has become simply 

 a good specific case on which to test the effectiveness of newly develop- 

 ing systems. 



The marine scientific community was actively involved from the 

 beginning of the first phase of operations. Atlantis 11., the recently 



