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Rear Admiral Henry T. Mayo, Commander-in-Chief, Atlantic Fleet, Standing Order Number One



6 April 1917.      

Standing Order No. 1.



1.  Each base for the fleet or a major portion thereof shall be selected with a view to its suitability in regard to:

     (a)  Practicability of preventing hostile submarines from reaching positions within torpedo range of any major ship.

     (b)  Practicability of guarding against floating mines.


2.  In order to assure protection against hostile submarines, it is necessary to anchor major ships at least six thousand yards from positions which may be reached by such submarines. If practicable, the obstructions should be so arranged that a straight run of a torpedo fired from any position outside of the obstruction will not pass into the area occupied by major ships, no matter what the range of torpedo.

3.  Shoals from [i.e., form] the most efficient protection against the passage of submarines provided the depth of water at high tide does not exceed twelve feet. The area of the entrance in which the water is of more than this depth can be most efficiently guarded by submarine trap nets.

4.  In order that vessels may enter and leave the base, it is necessary to have a gate through the net which can be opened at will. This gate should not be less than two hundred yards wide; should be marked by buoys and tended by a tug.


5.  A patrol of the net shall be established as follows:

     (a) Two launches, armed with a one-pounder, a machine gun, and rifles, one on each side of the net to guard against damage to the net and to observe the buoys by which the net is supported to see that they float properly, and to notify the patrol and guard ship of any indication that a submarine has been caught in the net, also to observe the opening in the obstruction when the gate is open.

     (b) Two launches, armed with a one-pounder, a machine gun and rifles, one each side of the net at sufficient distance from the net to warn approaching men of war or shipping of the obstruction, and of the method of procedure in gaining passage.

     (c) If available, two suitable vessels armed with guns, with steam up and anchors ready to slip, shall anchor outboard of the net, clear of the channel to the gate, with a view to acting offensively against any hostile submarine approaching, or entangled in, the net.

     (d) A suitable vessel shall be detailed as Guard Ship. She shall anchor inside of the net clear of the channel but close enough to the net to control the operation of the patrol and Gate Tug.


6.  The gate shall remain closed except when opened for the passage of shipping. Vessels must pass through the gate promptly upon signal being made by the Gate Tug that the gate is open.

7.  Vessels approaching the gate desiring to pass shall, during daylight, fly the international “P”. By night the signal shall be one red light displayed over a white lgiht [i.e., light].

8.  Vessels approaching the gate but not desiring to pass through shall, during daylight, fly international “K”. By night the signal shall be two white lights one over the other.

9.  Upon the approach of a vessel apparently desiring to use the gate or of one apparently unfamiliar with the with the existence of the obstruction, the Gate Tug shall hoist the danger flag by day, or exhibit a red li<g>ht if by night.

10. When the gate is open for passage the Gate Tug shall hoist the international “P” in place of the danger flag. By night, the gate being opened shall be indicated by a white light vertically over a red light.


11. All vessels approaching the obstruction shall be warned of its existence and informed of these orders.

12. Vessels except U.S.Naval Vessels and those using the gate for scheduled runs which are well known, shall not be allowed to pass through the gate at night, and shall be allowed to pass in daylight only after being boarded by an officer from the picket launch who shall, if there are no suspicious circumstances, pass her as far as the Guard Ship.

     The vessel shall be directed to anchor near the Guard Ship for further examination and shall be warned that is she fails to comply she will be sunk.

     An officer of the Guard Ship shall examine such vessel. The Commander of the Guard Ship shall pass her or report conditions to Commander Base Defense Force for action.

13. Sailing vessels of such draft as to necessitate opening of the gate for passage, shall be towed through by a picket launch or tug in order to decrease the time during which the gate is open.

     Sailing vessels and steamers of such light draft as to be able to pass outside the net sh<a>ll be informed of its presence and of the establishment of the patrol. They shall be required to report to a picket launch in the vicinity of the net before passing the obstructions, and to obtain permission to proceed.


14. The names of all vessels and of the masters informed of these orders shall be recorede [i.e., recorded] by each launch. Masters shall be notified that failure to comply with orders received will lead to prosecutio[n] before the Federal Courts.

     Vessels violating these rules shall be made to anchor near the Guard Ship for investigation.

     Special report of cases in which it is necessary to use rifle or gun fire to obtain compliance with these regulations shall be made to the Senior Officer Present at the Base.


16. Floating Mine Traps shall be installed in such positions as to guard the fleet against mines drifting with the current.

/s/ H.T. Mayo.                    

Campaign Order                    UNITED STATES FLEET

  No. 11                          U.S.S. PENNSYLVANIA Flagship

8 April 1917,           


(a)  Base Defense Force. Rear Admiral W.L. RODGERS.

     Guard Ship

     Two Picket Vessels

     One Tug

     Ten Picket Launches

(b)  Battleship Force plus PENNSYLVANIA_

(c)  Destroyer Force

(d)  Mine Force­_

1.   A submarine trap net is being placed across the YORK RIVER extending from black buoy number C-3 to the shoal bearing forty degrees from this buoy.1

     A drifting mine trap will be placed across the YORK RIVER just above the black buoy C-7. This trap will be constructed to permit passage through a marked channel.

2.   This force guard against attack b y submarines or damage by drifting mines.

3.   (a) Base Defense Force_ Control traffic in vicinity of obstructions and operate offensively against any hostile vessels approaching base. Maintain present patrol abreast of battleships reducing boats to two in each patrol.2

     (b) Battleship Force plus PENNSYLVANIA Supply ten picket launches to Base Defense Force. Launches to be armed with one pounder, a machine gun and rifles.

     (c) Destroyer Force Maintain detail of two destroyers as picket vessels in Base Defense Force.

     (d)  Mine Force Supply Guard Ship and Tug to Base Defense Force.

     (e) Execute nine April eight a.m. Destroyers and Picket luanches may be changed at discretion of Fleet Force Commanders after sufficient notice to permit proper instruction to reliefs.

/s/ H.T. MAYO, ADMIRAL.           


Source Note: Cy, DNA, RG 45, Entry 517B.

Footnote 1: On 29 March, Mayo had been ordered to have a submarine net made from material stored at Fort Monroe (Old Point Comfort, Hampton, VA). This net was to be placed at the entrance of Chesapeake Bay. See, Office of the Chief of Naval Operations [Opnav} to Mayo, 29 March 1917, ibid. The net was deployed in stages starting on 9 April; the last section was put in place on 17 April. See, Mine Force Commander to Opnav, 11 April and 16 April 1917, ibid.

Footnote 2: On 9 April, RAdm. William L. Rodgers issued orders to the Base Defense Force that clarified and expanded the orders issued here as to the role of that force and the procedures to be followed in protecting the entrance to Chesapeake Bay and the U.S. Atlantic fleet. Ibid.

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