EASTERN SEA FRONTIER
WAR DIARY
FEBRUARY 1942
  
     
 
CHAPTER VI
  
 
 
 
THE MINE FIELDS
  
     
 
        Long before we entered the war, plans had been made for the development of a system of passive defense for our coastline. Methods of cooperation between the Army and the Navy had been devised, submarine nets and booms had been manufactured, locations for mine fields had been selected. Even before the war began, mine fields had been laid in the more important harbors and naval bases. Immediately after December 7, the whole system of passive defense was greatly extended. Nets and booms were set in place, obstructions of all kinds were put across harbor entrances as fast as they could be manufactured, the area of existing mine fields was increased and new fields were sowed farther out to sea. All and down the coast these barriers were laid to secure the coastline from enemy attack. What form of direct action the enemy would take was not known, but it was possible, if not probable from the very beginning, that submarines, fleets of motor torpedo boats, and airplanes might individually or collectively attempt to attack the coast.
  
     
          During the past two months, plans have been made and steps undertaken to provide even more substantial means of defense that had existed heretofore. On January 15, an ambitious mining program was decided upon in Washington. The next day, the Chief of Naval OPerations proposed to Com One "that Navy contact mines be planted between Cape Cod and Cape Ann." It was estimated by the Chief of Naval Operations "that mine laying operations will begin on or about February 1, 1942, and will require 5 weeks, in favorable weather, for completion. The MONADNOCK and the MIANTONOMAH are expected to be available for laying the field." A letter of the same day amplified this proposal  
     
 
 
 
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  with recommendations for the size and character of the field.  
     
          Four days later, the Commandant of the First Naval District replied that the "plans and instructions were understood and considered possible of accomplishment as directed, provided additional floating equipment as herein indicated is assigned. --- Two additional lighthouse tenders to lay mid channel buoys in end passages and to serve as Dan layers are required. Lighthouse tenders now in the district could be made available but only to the detriment of net and boom projects already underway or authorized, of emergency servicing of aids to navigation and even of occasional emergency work. Three minesweepers -- are needed. No suitable minesweepers now available in the First Naval District. Eight patrol vessels of a type and size not less pretentious than 173' PC's are also needed. Patrol vessels now assigned First Naval District entirely inadequate for present tasks assigned Local Defense Forces."  
     
          On January 24, the Chief of Naval Operations replied that "six additional patrol vessels have been requested from Commander in Chief to the First Naval District. It is improbable that additional lighthouse tenders can be made available. Bureau of Ordnance is requested to supply necessary mines for this project."  
     
          The Commandant of the First Naval District reported on January 30, that PEQUOT would begin laying the indicator loops off Cape Cod the next day. He added that in his opinion "it is essential that the laying of mines should not be commenced until sufficient patrol vessels and minesweepers available." In all, his stated needs added up to seventeen vessels.  
     
          One week later, the laying of the field was postponed until February 20  
     
 
 
 
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  because of the extremely bad weather that had prevailed in the area and on February 16 the Commandant reported that "the present estimate for commencing the laying of the minefield is March 1, 1942. As previously stated, in case of bad weather or unfavorable sea conditions, this estimate may have to be revised.  
     
          High winds, freezing temperature, rough seas were not the only retarding factors; there was difficulty in obtaining the requite number of ships. As Commandant, First Naval District explained to Commander, Eastern Sea Frontier on February 19, 1942, "Assignment of vessels for mine patrol takes away practically all patrol vessels now in the First Naval District and available to Commander, Eastern Sea Frontier for offshore patrol."  
     
          At the time, January 16th., that the Chief of Naval Operations had written to the Commandant of the First Naval District about the Cape Cod mining project, he had also proposed to the Commandant of the Third Naval District that an extensive mine field be laid in the New York area. In a reply of February 5, Admiral Andrews raised several objections to the proposed field. There would be "grave danger to neutral and United States shipping -- unless traffic is held up during thick weather and weather too heavy for the small vessels of the patrol to maintain stations." Twenty vessels would be required in all to patrol the fields and guard the entrances. "The chances of a submarine passing through" the proposed field would be "approximately sixty six hundredths".  
     
          One week later the Chief of Naval Operations considered these objections at some length in a letter of February 13th. He believed the channels would be clearly enough marked for ships to pass through safely  
     
 
 
 
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  without danger in thick weather. The estimated number of patrol ships, it was stated, could be considerably reduced in practice. In answer to the argument that a submarine would have a chance of sixty-six one hundredths to pass through the field, it was estimated by Chief of Naval OPerations that the field would be 27% effective - which "appeared to be commensurate with the effort" expended.  
     
          During the next few days the question was the subject of a good deal of discussion and thought. The delay in the sowing of the Cape Cod to Cape Ann mine field lent some weight to the objections of those who opposed the laying of extensive mine fields. As a result of the deliberations, the Commander of the Eastern Sea Frontier, on February 21st., presented the Chief of Naval Operations with the following recommendations. It was "strongly urged that the whole subject of laying contact minefields in the waters of the Eastern Sea Frontier be reconsidered" for the following reasons:  
     
          "It has been established in conversations and by correspondence that the purpose of these mine fields is primarily defense against submarines. Defense against submarines is a large subject and has numerous factors geographical, tactical and otherwise, which should be carefully considered."  
     
          In the first place, all obtainable information indicated that the constant offensive action maintained by Great Britain against submarines both from the air and on the sea, kept the U-boats several hundred miles off the coast of the United Kingdom. "If such a result can be obtained by constant offensive action, there will be no immediate need for contact mine fields across the approaches to our harbors."  
     
 
 
 
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          In the second place, mine fields require protection and patrol. Vessels used for this purpose are diverted from the essential task of protecting shipping lanes and searching out and destroying enemy forces. Whether "the number of vessels (used) be great or small the principle holds. Mine fields are a menace to friendly vessels. To require the Frontier to protect friendly vessels from its own weapons is a task that should be forced upon it by the enemy -- not voluntarily adopted."  
     
          The significant point of all these arguments is that the main bulk or our strength could be better concentrated upon the central purpose than dispersed over a wide area in a purely defensive effort. The objections apparently convinced the Office of Naval OPerations, because on February 21, the Commandants of the First and Third Naval Districts were notified that all preparations attendant upon laying contact mines in the districts would be suspended.  
     
          The whole incident is a nice problem in the calculation of risks and conservation of energy. The arithmetical aspect of anti-submarine warfare noticed heretofore is once again apparent. With only a limited number of forces available, where could they best be used? It was obvious that additional minefields strengthened the defenses of the coast and were a form of excellent insurance, but in January and February it has been necessary to ask whether such insurance is needed and if it could be afforded.  
     
          A calculation of the risks seems to indicate that less danger lies in a possible future enemy attack off the coast than in the present warfare against our merchant shipping which is both costly and real. The immediate perils from this enemy action are great and the principle of concentration  
     
 
 
 
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  indicates that all forces should be brought to bear upon the point of present danger, the shipping lanes. This decision seems doubly correct because of the nature of the mine fields that were suggested. Unlike those laid in the North Sea during the last war, which were designed to obstruct the passage of submarines from their bases to the trade routes, the proposed fields were intended simply to protect certain areas against submarines that are already operating in richer and less hazardous hunting grounds.  
     
     
     
     
     
     
     
     
     
     
     
 

 

  
     
 
 
 
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