Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Secretary of the Navy Josephus Daniels
September 15, 1917.
From: Force Commander.
To: Secretary of the Navy (Operations).
Subject: Monthly meeting of Commanding Officers on vessels engaged in Anti-Submarine operations.
There was a conference on September 8 of Commanding Officers of destroyers and other vessels based on Queenstown on the general subject of Anti-submarine operations.
The conference discussed primarily the subject of handling convoys, and the conclusions of the conference are as follows:-
(a) Short distance radio between escort and convoy would be most useful. Visual signaling to the whole convoy from a destroyer is impossible; and very difficult to even two or three ships to get them to take it in. Megaphoning is usually resorted to, and takes a very long time, and in the case of foreigners who do not understand English or only a little is of course hopeless.
Most of the destroyers on this station have been fitted by the Dockyard here with a blackboard about 6’ x 4’; this is probably the best method yet found.
(b). It would be useful to have a special service vessel (mystery ship or “Q” ship)1 in a convoy, and when submarines are reported in the vicinity for her to drop astern as if unable to keep up, thus acting as bait. (This will be tried when there is a special service ship available).
(c) Twenty ships is considered the limit for a convoy to be properly guarded in all weathers.
(d) The best guide to tell ships when to stop zig-zagging on account of darkness or thick weather is that they should stop when the ships on either beam become indistinct, and start zig-zagging when they are plainly seen. Of course signals would be best as in a man-of-war squadron, but signals are not quickly seen by all ships in the convoy, nor readily understood.
(e) The leader should carry a diamond shape at both yard arms; if she has no yard one could be fitted before she sails.
(f) The upper after light should not be a hanging light but should be fixed on the after side of the after mast and screened so as to only show two points on either side of right aft, and not more than one mile astern when on an even keel.
(g) The radio operator in convoy ships should always go on watch on the approach of thick weather, and also before dusk and daylight so as to be ready to take in zig-zag or other signals.
(h) When the escort consists of trawlers they should be staggered along the sides of the convoy. Thus the leading trawlers on each side could be 1200 yards from the outside convoy ships; the next two trawlers astern could be 800 yards from the outside convoy ships; the next two trawlers astern 1200 yards and so on. The two destroyers attached to a trawler escort should be one ahead of the convoy and one astern, the latter well distant to prevent trailing.
(i) Convoys that steam below 8 knots should not zig-zag in the ordinary way, but should make a big alteration of course about every 1 1/2 to 2 hours: thus :- 2 points to starboard, - 2 points to starboard, -4 points to port, etc. This form of zig-zagging to be laid down and issued before sailing, but in several forms: A could be as above: B would be altering 2 points to port, - 2 points to port, - 2 points to starboard, etc.
(k) The following scheme is proposed as formation for escort with destroyers. . . .2
Wm. S. Sims
Source Note: Cy, DNA, RG 45, Entry 517B. Sims’ signature is handwritten. The heading “SUBJECT: Monthly meeting of Commanding Officers on vessels engaged in Anti-Submarine operations.” appears at the top of each page starting with page 2.
Footnote 1: For more on “mystery ships,” see: Fred M. Perkins to Sims, 10 July 1917.
Footnote 2: To view of copy of this diagram, see the illustrations page for September 1917.