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Naval History and Heritage Command

Naval History and Heritage Command

Rear Admiral Ralph Earle, Chief of Bureau of Ordnance, to Commanders of All Naval Forces

NAVY DEPARTMENT

BUREAU OF ORDNANCE

CIRCULAR LETTER #375

WASHINGTON, D.C.

To:  Commanders in Chief, Commanders all Forces.

     Commandants, Naval Districts.

     Commandants, all Navy Yards.

     Armed Guard Officers, Navy Yards.

     Inspectors of Ordnance in charge, Ammunition Depots.

     (See list attached).1

Subject:  Depth charges – Policy for issuing.

     1.   POLICY FOR ISSUIG DEPTH CHARGES.

I.   Distant Service Patrol Duty, (Destroyers, fast yachts).

(a) Speed of 15 knots or greater 10 Mark II.2

(b) Speed of less than 15 knots 10 Mark I, mod. I.

II.  Home waters, Patrol DutyRegular Navy or Section Patrol

(a) Speed of 15 knots or greater 4 Mark II.

(b) Speed of less than 15 knots 4 Mark I, mod. I.

III. Convoy Duty – Cruiser Force – United States Navy

Four (4) Mark II.

     Some of the cruisers have less than 15 knots speed, but are staunchly built and manned by regular forces.

IV.  Submarine Chasers 110 foot.

(a) Distant Service, 4 Mark II.

(b) Home waters - -, 4 Mark II.

V.   All other ships of the Navy engaged in trans-Atlantic, service having a speed greater than 15 knots – four (4) Mark II, if less than 15 knots speed – four (4) Mark I, mod. I as a weapon of opportunity.

     2.   A Supply of Mark I, mod. I and Mark II depth charges will be placed at the disposal of all concerned for issue in compliance with paragraph 1.

     3.   Weekly reports will be made to the Bureau showing the number and type of depth charges issued and names of vessels which have been outfitted.

Ralph Earle

Source Note: TLS, DNA, RG 45, Entry 520 Box 339. Document is dated with a stamp: “DEC141917.” Document reference: “[---]495(I-1)12/31/HW-7.” This document is printed on an Ordnance Bureau letterhead, with “CIRCULAR LETTER #375” stamped partially over the heading.

Footnote 1: This enclosure is not included with this document.

Footnote 2: “Mark I” and “Mark II” refers to different versions of depth charges.