Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Secretary of the Navy Josephus Daniels
SENT: June 12, 1917. TO: Secretary of the Navy
Twentyone. 21009. Letter follows next mail (stop) Necessary for safety that for future troop convoys rendezvous and routes be designated and controlled from here based upon latest information enemy activity (stop) Initial orders on sailing should be subject to change by radio after sailing (stop) Troop ships should zigzag together two to four point changes irregularly (stop) Destroyers should zigzag independently avoiding regularity of position in reference to convoy. In accordance with British experience when escorting cruiser enters dangerous submarine zone she is of practically no protection to convoy and virtually becomes one of convoy (stop) It is necessary in danger zone that radio be not used except for most important messages (stop) Evidence indicates that radio direction finders have been able to locate large forces or radio work of distinctive nature (stop) While in zone experience indicates that convoy commander should leave maximum initiative and freedom of movement to senior destroyer commander in view of his recent experience and later knowledge of enemy methods (stop) Enemy submarines do not have beam tubes (stop) Line <of division formation> column recommended with force concentrated as much as consistent with zigzagging. this to reduce visibility of the force and facilitate offensive operations of destroyers (stop) It is now practice here to furnish escort of one destroyer for single troop transport three for two transport four for three or four transports and one destroyer per transport when number is greater than four.
Source Note: Cy, UK-KeNA, ADM 137/656. At the end of the document is a columnar list: “Copies: Original./Confirmation./Chronological./Subject.”