Admiral Sir William Lowther Grant, Commander, North America and West Indies Station, to British Admiralty
Telegram rec’d from C.in C. NA & WI Date 13.10.18
To: ADMIRALTY P I N K
723 With reference to plan for dealing with Battle Cruiser raid following has been agreed upon by Navy Dept. and Admiral Duff1 and will come into force for all convoys leaving North America on or after 21st October and is to be known as Plan “BCR” (begins.)
(A) Raider warning will not be sent out (?without) mutual consent of Navy Department and Admiralty unless the evidence is conclusive.
(B) Warning will be in the form “Battle Cruiser Raider Action” followed by time (GMT) from which it is in force and will be sent in Convoy cypher. The latest reported position of enemy Battle Cruiser will be added if possible and later reports of enemy’s position will be broadcasted in Convoy cypher by shore stations.
(C) On the issue of this warning Navy Department Washington will take all action required as regards Eastbound Convoys whose time “A” (GMT) is later than time GMT given in raider warning. The time “A” GMT is to be estimated time at which convoy will cross long. 40 W.; this time should be (?fixed) before convoy sails and be included in sailing telegram sent to officers of Quarters. NOTE.- This division of sphere action by time instead of by actual position is necessary as it is not possible to know exactly whether a convoy has or has not crossed long. 40 W. at a given time.
(D) Dreadnought Battleships based on Berehaven will be detailed (under orders to be issued from London) to proceed to meet Troop Convoys whose time “A” is earlier than time GMT given in raider warning. They will only be sent to meet such of these convoys as can be met before reaching long. 20 W. On making contact the DREADNOUGHT should report the fact by W/T2 to London and should accompany convoy until further instructions are received. Any DREADNOUGHT battleships based on Berehaven which may be in excess of these requirements should be utilised to meet cargo convoys.
(E) DREADNOUGHTS based on Halifax or in other North American ports will be detailed by Washington to reinforce troop or other convoys as may be considered desirable at the time and will (?report to) Washington on making contact. The DREADNOUGHT will accompany on instructions being received but will not go to Eastward of 20 West unless so ordered.
(F) It is intended to have eventually either a pre DREADNOUGHT battleship or armoured cruiser with each convoy as far submarine danger zone. This escort is to remain with each convoy unless and until further orders are received except in the case of a convoy being joined by a dreadnought when the former escort will return her Atlantic port.
(G) Each convoy routed by North of Ireland is also to be given an alternative route by the South of Ireland; when time admits destroyer escort being diverted such convoys may be directed by London to the alternative route and Berehaven will be informed accordingly.
(H) Each convoy to be given as at present an ocean route showing where it will cross long 60<°> 50<',> [latitude] 40<°> 30<'> W. These routes to be given under general directions from Washington and to be notified in each case to London (as at present).
(I) Washington and London to keep each other closely informed of action taken in regard to the various convoys.
(1) Convoy cypher to be issued to all escorts and Commodores of Convoys and also to ships in fast U.S. troop convoys and monster ships which sail independently.
(2) Officers in charge of Convoys and (?Commodores) <of> convoys to be instructed in the sense above plan and also in accordance with wireless instructions contained in para. 2 clauses A to D of convoy instructions contained in Sim’s telegram 45 23 11th Sept.3
(J) No special plan will be adopted at present for West bound traffic which will proceed independently after dispersal from outward convoy. The aim should be to continue all voyages. Ships will be guided by warnings received and any instructions broadcasted (ends).
Source Note: Cy, DNA, RG 45, Entry 517B.
Footnote 1: RAdm. Alexander Duff, Assistant Chief of Naval Staff
Footnote 2: That is, wireless telegraphy.
Footnote 3: See: Sims to William S. Benson, 10 September 1918.