Change No. 3, Joint Action of the Army and the Navy, 1935

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J.B. No. 319-1 (Serial 653).

THE JOINT BOARD,
WAR AND NAVY DEPARTMENTS,
Washington, June 28, 1940.

The following changes in Joint Action of the Army and the Navy recommended by The Joint Board have been approved by order of the Secretary of War and by the Secretary of the Navy and should be made in all copies of this publication.

Add the following new pages.

Page Nos.	Subject matter
Id-Ie	Promulgation of Change No. 3.

Remove and destroy the pages listed below and substitute the reprinted pages containing changes as indicated.

Old page Nos.	Changes in reprinted pages
II-IIa 137-164	C.J.A. 3--List of effective pages (revised June 28, 1940) Chapter IX, revised, with diagrams Nos. I and II.

The office of The Adjutant General, War Department, and the Registered Publications Section, Navy Department, require no report of this change.

WILLIAM P. SCOBEY,
Lieutenant Colonel, Infantry,
United States Army, Secretary.

Joint Action of the Army and the Navy, 1935

List of Effective Pages

(Revised June 28, 1940)

Subject matter	Change in effect	Page Nos.
Title page	Original	No number
Navy letter of promulgation of November 15, 1935 (Navy copies only)	"	0-00*
Promulgation of Change No. 1, July 22, 1936	1***	I-Ia
Promulgation of Change No. 2, November 30, 1938	2	Ib-Ic
Promulgation of Change No. 3, June 28, 1940	3	Id-Ie
List of effective pages	3	II-IIa
Joint letter of promulgation of September 11, 1935	Original	III-IV**
Contents	2	V-VI
Contents, Part I	2	VII
Contents, Part I, continued	Original	VIII
Chapter I	"	1-2
Chapter I, continued	1	3-4**
Chapter II	2	5-6
Chapter III	2	II
Chapter III, continued	Original	12 to 16**
Chapter IV	"	17
Chapter IV, continued	2	18
Chapter IV, continued	Original	19-20**
Contents, Part II	"	21-22**
Contents, Chapter V	"	23-26
Chapter V	2	27
Chapter V, continued	Original	28 to 41
Chapter V, continued	2	42 to 44
Chapter V, continued	Original	45 to 47
Chapter V, continued	2	48
Chapter V, continued	Original	49 to 64
Chapter V, continued	2	65-66
Chapter V, continued	Original	67
Chapter V, continued	2	68
Contents, Chapter VI	2	69
Contents, Chapter VI, continued	Original	70 to 72
Chapter VI	"	73 to 76
Chapter VI, continued	2	77 to 80
Chapter VI, continued	Original	81-82
Chapter VI, continued	2	83-84

* Should be so numbered in ink in Navy copies only.
** Original blank pages IV, 4, 16, 20, and 22 should be so numbered in ink.
*** Navy copies "2."

Subject matter	Change in effect	Page Nos.
Chapter VI, continued	Original	85-86
Chapter VI, continued	2	87
Chapter VI, continued	Original	88 to 90
Chapter VI, continued	2	91
Chapter VI, continued	Original	92 to 97
Chapter VI, continued	2	98
Chapter VI, continued	Original	99-100
Chapter VI, continued	2	101
Chapter VI, continued	Original	102
Chapter VI, continued	2	103-104
Chapter VI, continued	Original	105
Chapter VI, continued	2	106-107
Chapter VI, continued	Original	108 to 110
Chapter VI, continued	2	111
Chapter VI, continued	Original	112
Contents, Chapter VII	Original	113-114**
Chapter VII	Original	115 to 126**
Contents, Chapter VIII	Original	127-128**
Chapter VIII	2	129-130
Chapter VIII, continued	1	131-132
Chapter VIII, continued	Original	133
Chapter VIII, continued	2	134
Chapter VIII, continued	Original	135-136**
Chapter IX	3	137-164
Chart of Organization for Coastal Frontier Defense	Original	No number
Diagram No. I, Coastal Frontier. Joint Radio and Wire Communications	3	No number
Diagram No. II, Joint Overseas Expedition--Landing Phase. Typical Communication Circuits for One Beach	3	No number

** Original blank pages 114, 126, 128 and 136 should be so numbered in ink.

Chapter IX¹
Communications

NOTE: References to Chapter VI are not linked. This Chapter was extensively revised in Change No. 2, which is missing from the edition available for this transcription. --HyperWar

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Section I
Policy for Coordination of Radio Activities of the Army and Navy[»]

1. Joint Board reports, J.B. No. 319 (Serial No. 183), of January 16, 1923, "Utilization of the radio services of the War and Navy Departments for the transmission of Government dispatches," and J.B. No. 319 (Serial No. 253), "Proposed draft of Executive Orders re regulation of radio in the event of war or national emergency," are rescinded. The following policy, approved by the Secretary of War and the Secretary of the Navy, is published for information and guidance:
1. Purpose of Radio Policy.

   2. The purpose of this statement of policy is to establish an authoritative basis for the coordination of the Army and Navy in the development of radio material, the establishment of radio stations, and in the conduct of radio activities.

2. Basic Policy.

   3. The Army and Navy shall provide, control, and operate such transmitting and receiving stations as, augmented by private and other Government-owned radio facilities, will insure the existence and availability upon the outbreak of war or other national emergency of a militarily controlled, thoroughly indoctrinated radio system adequate to meet the requirements of national defense, having in view the prevention of undesirable duplication and the practical and definite limitation on expenditure imposed by economy.

3. Primary Responsibility of the Army and the Navy in Radio Activities.

   4. 1. The assignment of primary responsibility to the Army or to the Navy for radio activities serving a definite area or purpose imposes upon the designated service the responsibility for the establishment and efficiency of radio serving such area or purpose, but allows the other service to use radio to serve the same area or its own purposes of a similar nature, provided no serious radio interference is caused thereby.

      2. In war time unity of command in certain areas or theaters of operation may be assigned to the Army or the Navy, in accordance with the approved War Plans, and radio activities therein will be coordinated by the responsible commander of the service in which such unity of command is vested.

      3. In order to avoid uneconomical duplication in time of peace:

         1. The Navy only shall operate radio apparatus of high power (10 kilowatts in the antenna or greater).

         2. The Army shall not handle overseas radio communications commercially or for other Government departments except between the United States and Alaska, nor operate upon frequencies which will cause serious interference with Fleet or Navy overseas circuits.

4. Assignment of Primary Responsibility.

   1. Subject to the provisions of subparagraphs (a) and (b) of the preceding paragraph, primary responsibility is assigned as follows:

      1. To the Army in radio communication--

         1. With and between Army units wherever located.

         2. Within the Territory of Alaska.

         3. With and between Army vessels, excluding such vessels as may be placed under Navy control.

      2. To the Army in radio intelligence--

         1. For the Army wherever operating.

      3. To the Navy in radio communication--

         1. For the establishment, maintenance,and operation of an overseas radio service for efficient communication with and between Navy units wherever located; this service to be available to all departments of the Government and for commercial purposes.

         2. For communication with insular possessions, the Panama Canal Zone, and with foreign territory occupied by the Navy.

         3. With and between ships at sea, exclusive of Army vessels, except such of the latter as may have been placed under Navy control in case of war or national emergency.

4. For the establishment and operation of radio-compass stations along the coasts of the United States, Alaska, overseas possessions, or occupied foreign territory.
4. To the Navy in radio intelligence--

   1. For the Navy wherever operating.
5. War-time Jurisdiction over Nonmilitary Radio.

   6. In time of national emergency, when directed by the President according to law, the Army and the Navy will assume jurisdiction as follows:

      1. The Army and Navy shall each assume complete control over such nonmilitary radio stations as may be allocated to them by the President to augment their peace-time facilities.

      2. For purposes of censorship and supervision over such nonmilitary radio stations as are permitted to operate:

         1. The Army will assume jurisdiction over all nonmilitary stations within the United States, Alaska, and foreign territory occupied by the Army except the stations assigned to the Navy in the following paragraph:

         2. The Navy will assume jurisdiction over all nonmilitary stations wherever located that are permitted to communicate overseas, with ships, or with aircraft flying over the sea other than Army aircraft, and over all nonmilitary stations in Panama, the insular possessions, and in foreign territory exclusively occupied by the Navy.

      3. For the purpose of suppression of unauthorized radio:

         1. The Army will assume jurisdiction over the continental United States, Alaska, Panama, and in insular possessions or foreign territory occupied by the Army.

         2. The Navy will assume jurisdiction over shipping and over insular possessions or foreign territory occupied exclusively by the Navy.

6. Principles to be Observed in Radio Coordination.

   7. Coordination in radio operation will be effected:

      1. In the development of types of radio equipment suitable for intercommunication.

      2. By the assignment of call letters, frequencies, transmitting time periods, the adoption of a common procedure, and the formulation of codes and ciphers for joint Army and Navy communication.

      3. All air radio stations of the Navy and air radio stations of the Army along the coast and in the insular and outlying possessions shall be equipped to send and receive on a common intermediate frequency and a common high frequency, and all aircraft carrying radio, except fighting and pursuit planes, shall as soon as practicable,

consistent with proper economy, be equipped to send and receive on one of these common frequencies.
4. The radio field sets provided for the use of the Marine Corps on shore shall be capable of intercommunication with the radio provided for the operation of similarly equipped units of the Army.

5. The radio communication equipment provided for the vessels of the Army Transport Service shall be of a character normally provided for commercial shipping of the same general class and shall be capable of sending and receiving on at least two frequencies assigned by the Navy Department for Naval Transportation Service communication.
7. Coordination with Radio Stations of Other Departments and Civilian Stations During Peace.

   1. Coordination of the operation of Government radio stations with each other and with the operation of civilian radio stations in time of peace will be governed by the provisions of the radio act of 1927 (secs. 6, 8, and 25).

8. Coordination of Development Programs.

   9. The Chief Signal Officer of the Army and the Director of Naval Communications will coordinate the peace-time radio operation and operational development of the two services. The Chief Signal Officer of the Army and the Chief of the Bureau of Engineering of the Navy Department will coordinate their recommendation for the procurement programs of the Army and the Navy and will coordinate technical radio matters of joint concern to the two services.

Approved by the Secretary of War and the Secretary of the Navy June 24, 1927.

Section II
Doctrines and Guides Governing Communication (Signal) Effectiveness in Joint Operations of the Army and the Navy

			Paragraphs
Subsection I.	General		156-158
II.	Coastal Frontier Defense		159-162
		Joint channels and means of inter-communication	159
		Aircraft communication principles	160
		Aircraft warning service	161
		Preparation and distribution of communication (signal) plans and instructions	162
III.	Joint Overseas Expedition		163-168
		Introduction	163
		General	164
		General principles	165
		Aircraft communication principles and aircraft warning service	166
		Joint communication (signal) training	167
		Special equipment	168
IV.	Communication Security		169-171
		General	169
		Grouping of Army and Navy units into categories for classified communications	170
		General instructions	171
V.	Joint Communication (Signal) Plan		172
		General	172
VI.	Miscellaneous		173
		Other joint communication requirements	173

Subsection I--General

156. Effective signal communication in joint operations of the Army and Navy requires--

     1. The interconnection of the appropriate elements of the Army and the Navy by the appropriate means of signal communications.

     2. Joint communication (signal) training.

     3. The preparation and proper distribution of important items of information and instructions governing signal communication.

     4. Appropriate provisions for communication security.

     5. Adequate provision for cryptographing.

157. The information presented hereinafter should serve as a guide, to indicate--

     1. The elements that are to be interconnected during joint operations.

2. The distribution that should normally be given important items of information and instructions governing signal communication.

3. The cryptographic systems to be employed in joint operations.

4. The essentials of a Joint Communication (Signal) Plan.
158. Miscellaneous considerations.--Details for communication between the Army and the Navy shall be made by the senior officers of the two services in the area concerned. The following items are here presented for the guidance of all concerned:

     1. Liaison officers.--The importance of detailing qualified liaison officers for joint operations is indicated in chapter V, section V, paragraph 42i(15) and in chapter VI, section II, paragraph 51.

     2. Means and methods of communication.--All suitable means of communication are to be considered available for joint use. When a choice is available, the most reliable means should be selected, with due consideration for speed and security. Attention is particularly invited to the advantages of effecting simultaneous delivery of messages to numerous addressees by radio broadcasting (F-method) without obtaining a receipt, or by teletype in case addressees are all on a teletype net. Scheduled F-method radio transmissions should usually be on an especially prescribed frequency and should be regularly copied by most addressees. Such transmissions should be relayed to those addressees who either are not able to copy, or are not required to copy them. However, F-method transmissions may be made at any time on the same frequency as that usually employed for the 2-way R-method (i.e., in which receipts are obtained for each message transmitted).

     3. [»] Precedence.--In the absence of specific instructions to the contrary, messages of the same precedence, whether originating in the Army or the Navy, will be handled in the order of filing for transmission, or of receipt for relaying. Messages are divided into precedence groups to show the relative order in which they shall be transmitted and acted upon. This order is as follows:

        1. The URGENT designation is reserved for messages requiring the greatest speed of handling. Any message designated as URGENT will be sent immediately upon receipt, except when communication involving another URGENT message is being carried on. URGENT precedence is reserved for use during combat, or when combat is imminent, real or simulated, to indicate that the message so designated conveys the most important orders, information or request pertaining to the combat,

and thus requires immediate attention. A primary example of this type of message is a so-called Army "flash" message which is employed to report air observation of surface or air forces and ground observation of air forces. For joint communication purposes, an Army "flash" message may be considered to be an urgent message of the highest priority. A primary example of a Navy message of the highest priority is a major contact report.
2. The PRIORITY designation is reserved for messages of less urgency than those entitled to URGENT precedence, but of such nature as to warrant precedence ahead of messages designated as ROUTINE or DEFERRED. Any message designated as PRIORITY will be transmitted before any routine or deferred messages which may be awaiting transmission, but transmission of a short routine or deferred message will not usually be interrupted to send a PRIORITY message.

3. The ROUTINE designation is reserved for messages requiring no special precedence. They are transmitted in the order in which they are received or in such order as will clear the traffic most expeditiously. Any message designated as ROUTINE usually will be transmitted before any deferred messages which may be awaiting transmission, but transmission of a short deferred message will not usually be interrupted to send a ROUTINE message.

4. The DEFERRED designation is reserved for messages requiring no special precedence, and whose delivery to the addressee may be delayed until the beginning of office hours following the day on which they are file.d. This will sometimes necessitate transmission of Deferred messages ahead of Routine messages, in order to effect delivery before the time indicated.
4. Address and signature.--While all official messages will be sent by authority of the commanding officer, no signature will ordinarily be transmitted. Messages intended for an addressee on board a ship or airplane, or within a command onshore, will be routed by use of the appropriate call sign of the ship, airplane, or shore command. Delivery to any specific addressee within the ship, airplane or shore command is a function of the command to which delivered.

If call signs are assigned for joint use to particular commanders, as well as to particular ships, airplanes and shore commands, such commander call signs may also be employed to indicate routing, addressees and originators.
5. Use of clear or cryptographic language.--The general rules governing the use of clear and cryptographic language are set forth in subsection IV of this chapter, wherein communication security is discussed.

6. Operating instructions and procedures.--Operating instructions are special instructions for transmitting, receiving, and when required, for relaying messages. These instructions are set forth in a separate restricted pamphlet entitled, "Joint Army and Navy Radio Procedure."

7. Time.

   1. The time of origin is the time at which the message is released or authenticated by the originator. If this time does not appear on the message, it will be the time when the message is filed for transmission.

   2. The time of origin in joint communications is expressed in the 24-hour clock system and transmitted as a group of four figures, the first two digits representing the hours from midnight and the last two the minutes past the hour.

      Examples: 6:00 A.M. is 0600, and 7:43 P.M. is 1943.

   3. For communication within the Army, the 12-hour clock system is used.

      Examples: 6:00 A.M. is 600 A, and 7:43 P.M. is 743 P.

      [»]

8. Dates.

   1. The date is expressed for joint communication purposes by two figures preceding the time of origin, indicating the day of the month. If the date number is less than ten, it is always preceded by zero. For example, the first day of the month is 01, and the tenth day is 10. "071626" means date was 7th day of month, and time of origin was 1626.

   2. The month and year may be added to the date and time of origin group when necessary for reference purposes in the text of messages. For example: "Your 071626 DEC 1938" means "Referring to your message, with time of origin 1626 on the 7th day of December 1938 * * *".

3. In the text of messages, if times indicated are not given particular descriptions, the time prescribed for use by the originator shall be understood.
9. Addressees.--In drafting messages, the various classes of addressees may be indicated:

   1. Action addressees.

   2. Information addressees.

   3. Both action and information addressees.

Subsection II--Coastal Frontier Defense

159. Joint channels and means of intercommunication (See ch. V, Sec. III, Par. 32h(3) and Diagram I.).--The radio, visual, and wire communication which may be required between the two services in joint coastal frontier defense operations are indicated below. Certain Army-to-Army communication circuits and certain Navy-to-Navy communication circuits are also included where considered desirable to indicate the more important of such circuits. No attempt has been made herein to prescribe the number of separate circuits to be provided between stations. The number and the type of circuits should be determined in each case by the nature and amount of the traffic to be transmitted and by geographical considerations. If practicable, separate wire circuits should be provided for command, intelligence, and administration.

     1. Coastal frontier headquarters (Army).

        1. Wire to: Various naval district headquarters within the coastal frontier.

        2. Radio (2)* to: Various naval district headquarters within the coastal frontier.

     2. Corps area headquarters.

        1. Wire to: Nearest naval district headquarters.

        2. Radio (2)* to: Nearest naval district headquarters.

     3. Sector headquarters (Army).

        1. Wire to: Nearest naval district headquarters.

        2. Radio (2)* to: Nearest naval district headquarters.

     4. Subsector headquarters (Army).

        1. Wire to: Inshore patrol headquarters.

        2. Radio (2)* to: Nearest naval district headquarters from those subsector headquarters that are identical with defensive coastal area headquarters and harbor defense headquarters and forts.

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(2)* Indicates radio two ways--for transmitting and receiving, to be placed in operation if wire is not available, or fails for any reason.

3. Radio (2)* to: Inshore patrol. This communication will necessarily be on the frequency assigned for communication between ships and inshore patrol headquarters. Subsector headquarters normally only intercepts radio messages from the inshore patrol to inshore patrol headquarters, but may transmit also, when necessary.

4. Wire through: Sector headquarters to nearest naval district headquarters--for receiving information from the offshore patrol.
5. Harbor Defense Headquarters.

   1. Wire to: Inshore patrol headquarters.

   2. Radio (2)* to: Inshore patrol headquarters from harbor defense headquarters that are located at forts.

6. Forts (Army).

   1. Wire to: Inshore patrol headquarters through subsector headquarters.

   2. Radio (2)* to: Inshore patrol headquarters.

7. Army aviation headquarters.

   1. Radio (1)* to: Navy airplanes, when required.

   2. Wire to: Navy air station (if in coastal frontier).

   3. Radio (2)* to: Navy air stations.

8. Army reconnaissance airplanes (1)* (5)*.

   1. Radio to:

      1. Navy airplanes (in emergencies and/or when jointly engaged in a mission).

      2. Navy air station (in emergencies and/or when operating therefrom).

      3. Inshore patrol (via inshore patrol headquarters when engaged in joint missions with the inshore patrol).

      4. Offshore patrol ships (in emergencies and when Army airplanes are assigned offshore patrol missions).

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(2)* Indicates radio two ways--for transmitting and receiving, to be placed in operation if wire is not available, or fails for any reason.

(1)* See par. 160--Aircraft communication principles.

(5)* Circuits for use in emergencies are not shown in diagram I.

2. Visual to: Inshore and offshore patrols.
9. Army and Navy airplanes (combat) (1)* (When present in coastal frontier defense).

   1. Radio (4)* to:

      1. (For air command purposes) between squadron, group and higher commanders of Army and Navy joint task force elements.

      2. (For air and air-ground liaison purposes) between reconnaissance and scouting airplanes, and the commander of the joint task force. Also, between squadron, group, and higher commanders of Army and Navy joint task force elements. Between reconnaissance aviation or bombardment aviation and the following:

         1. To elements of the fleet at sea (if present).

         2. To the joint task force headquarters--air (Army or Navy). Also, between pursuit, fighter, and bombardment aviation and Navy air station and/or Army aviation headquarters from which operating as well as with the headquarters of antiaircraft regiments and antiaircraft gun battalions (for recognition purposes).

10. Navy airplanes (1)* (5)*.

    1. Radio to:

       1. Army airplanes (in emergencies and/or when jointly engaged in a mission).

       2. Army aviation headquarters (in emergencies and/or when operating therefrom).

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(1)* See par. 160--Aircraft communication principles.

(4)* Not shown on diagram I, being too variable.

(5)* Circuits for use in emergencies are not shown in diagram I.

2. Visual to: Land antiaircraft defenses.
11. Navy air station (If present in coastal frontier).

    1. Radio (1)* (5)* to: Army airplanes (in emergencies and/or when operating therefrom).

    2. Wire to: Army aviation headquarters.

    3. Radio (2)* to: Army aviation headquarters.

12. Offshore patrol ships (Navy).

    1. Radio (1)* (5)* to: Army airplanes (in emergencies and when Army airplanes are assigned offshore patrol missions).

13. Inshore patrol ships (Navy).

    1. Radio (1)* to:

       1. Army airplanes, via inshore patrol headquarters when engaged in joint missions with inshore patrol.

       2. Forts.

       3. Subsector headquarters (when identical with defensive coastal area and harbor defense headquarters).

    2. Visual to: Batteries, forts.

    3. Visual to: Those subsector headquarters which are identical with defensive coastal area and harbor defense headquarters.

    4. Visual to: Outpost forces (if present).

14. Inshore patrol headquarters.

    1. Wire to: Subsector headquarters.

    2. Wire to: Harbor defense headquarters.

    3. Radio (2)* to:

       1. Subsector headquarters (if identical with defensive coastal area and harbor defense headquarters).

       2. Harbor defense headquarters when located at forts having 5radio facilities.

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(1)* See par. 160--Aircraft communication principles.

(2)* Indicates radio two ways-for transmitting and receiving, to be placed in operation if wire is not available, or falls for any reason.

(5)* Circuits for use in emergencies are not shown on diagram 1.

15. Naval district headquarters (3)*.

    1. Wire to: Nearest corps area headquarters.

    2. Wire to: Nearest subsector headquarters.

    3. Wire to: Coastal frontier headquarters.

    4. Wire to: Nearest sector headquarters.

    5. Radio (2)* to: Coastal frontier headquarters.

    6. Radio (2)* to: Nearest corps area headquarters.

    7. Radio (2)* to: Nearest subsector and sector headquarters.

    8. Wire to: Information Center, Aircraft Warning Service.

16. Coastal force.

    1. Radio to:

       1. Naval district headquarters.

       2. Commander offshore patrol.

17. Escort force.

    1. Radio to:

       1. Naval district headquarters.

       2. Commander offshore patrol.

    2. Visual to: Army and Navy units as necessary.
160. Aircraft communication principles.--The following principles governing aircraft communication should usually be observed in joint coastal frontier defense:

     1. When Army or Navy airplanes are used jointly as a part of a task force organization, the frequencies for communication would be as prescribed by the Army or Navy commander of the task force.

     2. When not otherwise specifically provided, Army airplanes will work with Army ground stations and Navy airplanes will work with Navy stations afloat or ashore.

     3. In emergencies, if the Army wishes to communicate directly with a Navy airplane, the Army will utilize a frequency which is known to be guarded by that Navy airplane. Similarly, when the Navy wishes to communicate directly with an Army airplane, the Navy will utilize a frequency which is known to be guarded by that Army airplane.

     4. Airplanes will not be required to shift frequency for joint communication purposes while in the air. Any airplane which is able to communicate on more than one frequency at a time may do so when required.

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(2)* Indicates radio two ways--for transmitting and receiving, to be placed in operation if wire is not available, or fails for any reason.

(3)* In certain areas it may be practicable and desirable for communication purposes to have various shore headquarters located in the same building, or sufficiently close to facilitate intercommunication and cooperation.

5. It is expected that those various commands of the Army and Navy, which may have need of information to be transmitted by particular aircraft of either service, will, whenever practicable, arrange to receive such information direct, by having receiver (intercept) watches set on the aircraft frequencies involved.

6. Normally, all joint radio communication, except for command purposes between airplanes in flight, should be by radiotelegraph.
161. Aircraft warning service.--The various elements of the Army and the Navy involved in joint operations must be interlinked with an Aircraft Warning Service Information Center in a communication net that will insure the prompt reception and distribution of warnings of the approach of enemy aircraft. While the elements included in this net will vary according to conditions, the information center should usually be connected with the following for the purpose indicated:

     The reception of warnings from--

     Civilian reporting stations.
     Army elements:

     Ground reporting stations.
     Aviation elements engaged in missions which would enable them to advise of approach of hostile aircraft.*
     All Army elements in a position to report the approach of hostile aircraft.
     Naval elements:
     Escort Force.*
     Coastal Force.*
     Offshore patrol:
     Airplanes*
     Ships*
     Inshore patrol:
     Airplanes*
     Ships*
     Naval direction finder stations.*
     Coast Guard stations:
     Lighthouses.

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* Information Center radio receivers will intercept for this purpose the normal frequencies which these elements are using.

The distribution of warnings to--

Army aviation headquarters for the warning of:†

Army aviation bases.
Army aviation elements.
Army aviation fields.

Air defense headquarters.† (When present in coastal frontier.)

Antiaircraft artillery headquarters.† (When an air defense headquarters is not located in the coastal frontier or when so located, it does not control all antiaircraft artillery defense elements in the coastal frontier.)

Coastal frontier and/or Army or corps area headquarters (for the warning of civilian population and Army ground elements and establishments and establishments).&dagger

Naval aviation headquarters (for the warning of naval aviation units.)†

Naval district headquarters for warning of:†

Navy bases--air, ship, and submarine.

Navy yards and other Navy shore establishments.

Escort force.

Coastal force.

Offshore patrol.

Inshore patrol.

All units of fleet present.

162. Preparation and distribution of communication (signal) plans and instructions (See ch. VI, sec. VI, par. 77 and Sec. VIII, par. 108a).--It will be necessary for each service to have certain items of information and publications pertaining to the other service. The items of information as well as the distribution should be prepared to suit each operation. The importance of early preparation and distribution of these plans and instructions should be impressed upon all concerned. For illustrative "Joint Communications (Signal) Plan," see paragraph 173.

Subsection III--Joint Overseas Expeditions

163. The specific circuits for the movement overseas of a joint overseas expedition are not herein presented diagrammatically, as in the case of joint communication for coastal frontier defense, since each joint overseas expedition presents a varied set of forces and conditions. However, the following discussion is intended to cover all major items concerning communication for any joint overseas expedition,

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† These elements are connected by wire with the Information Center. Aircraft warnings may be distributed by radio broadcast.

and to serve as a guide therefor. Diagram II should be considered merely as a guide to indicate the joint circuits which may be employed during the landing phase of an oversea expedition. The circuits and the number and type thereof should be determined in each case by the nature and amount of traffic to be transmitted and by geographical considerations.
164. General (See ch. VI, sec. III, par. 54.)--Many of the measures necessary to insure effective communication (signal) in joint overseas expeditions must usually be completed prior to, and during, the embarkation phase. Prior to this phase, the following measures should be undertaken: (1) the design and production of the appropriate equipment and publications which will be required for communication (signal) between the Army and the Navy, and (2) the training of communication officers and enlisted men of both services that will participate in the joint overseas operations in the use of prescribed joint communication procedure and methods. During the embarkation phase, the necessary communication (signal) plans and instructions should be prepared, distributed, and studied, and the particular training required for communication and for security should be undertaken.

165. General principles.--The following general principles which concern communication have been established:

     1. During the movement overseas, the Army and Navy commanders of a joint overseas expedition, with their respective staffs, should be embarked on the same ship, as should the commanders of a joint attack force, and, where practicable, this method should be extended throughout all echelons of command. Each transport should have a communication center operated by Navy personnel. The complement of this center will be augmented by the addition of Army personnel who will remain on duty therewith until their services are no longer required for the routing of messages pertaining to the Army. The communication (signal) officers should be informed of--

        1. The particular ships in which the commanders of their next subordinate and next superior units are embarked.

        2. The naval communication arrangements for handling communications between the ships, mentioned in (1) above, to the end that they may arrange for the transmission of orders and information under the circumstances.

     2. (See ch. VI, sec. II, par. 50-52.) The liaison officers exchanged between the commands of the Army and the Navy should have copies of the cryptographic systems of their own service for handling messages applying particularly to that service. These liaison officers may have messages transmitted in these systems, regardless of the service

operating the agencies of communication (signal), provided the restrictions on communication (signal) then in effect, are not violated.
3. Landing phase (See ch. VI, sec. VI, par. 82, and sec. VIII, par. 109.).--The Navy, during the landing phase will--

   1. Have responsibility for shore-ship communication, and communication with Navy boats used for landings.

   2. Have the beachmaster establish a communication center at each landing place to handle communication between ship and shore. (See ch. VI, sec. VI, par. 101a.)

   3. Provide a naval liaison detachment to accompany each combat team to provide the radio and visual communication and operation facilities necessary for effective naval gunfire support of the combat team. (See ch. VI, sec. VI, par. 93a, 94b and c.) (See also par. 168b.)

4. As soon as possible, the Army will establish all of its own signal communication for combat, and, in addition, provide wire communication and messenger service from the command post of each Army combat team to the commander of the naval liaison detachment assigned to accompany that particular unit.

5. The Army shore party commander will establish a message center at each landing place and will connect by wire and messenger service with the Navy beachmaster's communication center at that landing place. (See ch. VI, sec. VI, par. 101a, c, and d, and sec. VIII, par. 109).
166. Aircraft communication principles and aircraft warning service.--So far as they are applicable to communication in a joint overseas expedition, the principles set forth in paragraphs 160 and 161, in connection with joint coastal frontier defense, should usually be observed.

167. Joint communication (signal) training.--The various elements of the Army and the Navy to be jointly trained are indicated below. In particular, training during the embarkation phase should include communication between the elements which will have to communicate during the landing phase, the familiarization by all concerned with the cryptographic systems prescribed for all phases.

     1. Army and Navy aviation elements.

        1. Navy observation airplanes.--Even though Army observers may be provided in Navy observation airplanes, it is essential that Navy personnel therein be trained as indicated below, since in the early phases of the landing they will usually be required to undertake liaison, reconnaissance, and Army artillery adjustment missions.

1. In communication with the ground units to be supported during the landing.

2. In recognition of Army panel and pyrotechnic signals used in lieu of radio.

3. In picking up messages from and dropping messages to ground troops.

In addition, such Navy personnel should be cognizant of so much of the communication plans and instructions issued to ground troops as may be necessary for effective operations.

2. Navy reconnaissance and spotting airplanes.--The Navy personnel engaged in air reconnaissance and air spotting of Navy gunfire in support of landing operations should be trained in the pyrotechnic and panel signals displayed by ground troops, particularly those used to indicate:

   Location of front lines.
   Gunfire is falling short.
   Lift gunfire to next objective.
   Put down gunfire on a particular objective.

3. Navy observation airplanes with Army observers.--Army observers who may be assigned to Navy observation airplanes during the early phases of a landing on missions involving liaison, reconnaissance, and Army artillery adjustment should be trained in the use of the Navy radio equipment and in Navy spotting procedure.

4. Combat aircraft task forces.--It is especially important that the combat elements of the aviation task forces of both services be jointly trained in communication (signal) methods and procedure to the end that the highest degree of effectiveness may be attained in the operations of such joint task forces as will be required to support the landing operations.
2. Other elements of both services.

   1. Army ground elements.--All Army ground elements should be trained to distinguish friendly Naval aircraft from hostile aircraft. In addition, the personnel of those Army radio stations that will be required to communicate with Navy airplanes engaged in reconnaissance, liaison, and Army artillery adjustment missions should receive training in communicating with the Navy aviation personnel that will be assigned to cooperate with them in the actual landing. Elements of the antiaircraft defense forces should be informed of the recognition signals (visual or radio) that will be employed by Navy aircraft operating in support of the landing.

2. Naval liaison and communication detachments.--Naval liaison officers and Naval communication (signal) detachments assigned to accompany the Army assault elements (in order to handle the observation and communication (signal) required to bring about effective Naval gunfire support of the Army assault units) should be trained in the use of--

   1. The mobile field radio equipment required.

   2. The Army visual (including pyrotechnic) signals, particularly those used to indicate--

      Landing successful.
      Landing not successful.
      Reached objective.
      Location of front lines.
      Gunfire is falling short; and lift gunfire to next objective.
      Put down gunfire on a particular objective.

      This liaison and communication personnel through rehearsals in the embarkation phases should be familiarized with the operations of ground troops and the other means of communication that are available in case it is necessary to use the Army Communication (signal) system to get Naval messages back to the commander of the Naval fire support group via the Naval beachmaster (see par. 168b).

   3. Liaison officers.--Liaison officers who are exchanged between the higher elements of command of the two services should be thoroughly familiar with--

      1. Provisions governing responsibility for communications during the various phases of a joint overseas expedition.

      2. Actual command "set-up" of the communication systems.

      3. Rules of both services governing communication security.

   4. Communication officers.--All communication officers should be made cognizant of the following, during the embarkation phase:

      1. The three items listed in (3) above under liaison officers.

      2. The communication channel requirements, cryptographic systems and frequency plans for all phases. (See ch. VI, sec. VII, pars. 104 and 107.)

168. Special equipment.--The special communication (signal) equipment that should be provided and with which the personnel concerned should be thoroughly familiarized prior to and during the embarkation phase consists in general of the following items (i.e., when normal equipment of the particular element will not meet the needs of the situation):

     1. Radio sets that will permit of intercommunication between the airplanes of such joint task forces as may be established.

     2. Radio sets for such Navy liaison detachments as are to accompany the Army combat teams. These sets should be of appropriate size and weight to permit ready transportation to all locations where an infantry battalion command post may be established, and should permit direct communication between the Navy liaison detachment commander and the commander (and ship) of the Navy fire support group which is supporting the operations of the particular Army combat team. As it is probable that radio equipment now available for this purpose may not be effective under all conditions to be encountered, substitute means for this communication should be provided--such as aircraft radio or Army wire back to the beachmaster and thence by radio to ship concerned.

     3. Cryptographic systems for joint communications during all phases of the operation, including sufficient Army fire-control and air-ground liaison codes to supply copies to all Navy observation airplanes assigned to Army reconnaissance, liaison, and artillery adjustment missions.

     4. Radio sets for the beachmaster, for the small boats, used in the landing, and possibly for transports of such characteristics as to permit direct communication between units linked, as shown in Diagram II.

     5. Pyrotechnics for use in the landing boats and on the beach. When Navy airplanes are assigned to Army reconnaissance, liaison, and artillery adjustment missions, arrangements shall be made, if practicable, to permit communication between the Army ground stations and Navy airplanes.

Subsection IV--Communication Security

169. General.--

     1. Classified communication between the Army and the Navy will be divided into the following security classes:

        1. Secret.--Messages and written communications will be classified and marked secret when disclosure of the information contained therein might endanger national security, cause serious injury to the interests or prestige of the nation or any governmental activity, or would be of great advantage to a foreign nation.

2. Confidential.-Messages and written communications will be classified and marked confidential when disclosure of the information contained therein, although not endangering the national security, might be prejudicial to the interests or prestige of the nation, a governmental activity, or an individual, or be of advantage to a foreign nation.

3. Restricted.--Messages and written communications will be classified and marked restricted when information contained therein is for official use only, or when its disclosure should be limited for reasons of administrative privacy or denied the general public.

Secret, confidential, and restricted messages and written communications, plus the information contained therein, will be handled and safeguarded in a manner appropriate to the classification, as defined above, and in accordance with the instructions of the service(s) concerned.

2. The following doctrines will govern in the classification of messages and the use of the various cryptographic systems:

   1. Reliability, security, and speed.--Reliability is paramount and shall never be sacrificed for security or speed.

   2. Use of clear and cryptographic language.

      1. In time of war or emergency, all messages to be transmitted by radio, or by other means when danger of hostile or unauthorized interception exists, are cryptographed except in the following cases: when the tactical situation is such that time cannot be spared for cryptographing or the information to be transmitted if intercepted by the enemy could not be acted upon in time to influence the situation in question,a commanding officer or his authorized representative may order the transmission of a message in plain language. Such messages will be marked "Send in clear", over the signature of the commander or his authorized representative.

      2. So far as practicable, during joint exercises and joint communication training exercises, each message will be given the same classification and handling as would be given to the same subject matter in war.

   3. Mutual observance of classifications.--The classification of a message with respect to security may be changed only by the originator of the message or by superior authority.

4. Rules governing communication security.

   1. The communications of one service must not be permitted to compromise the operations of the other service.

   2. Radiotelegraph is the preferred method of joint Army-Navy radio communication.

   3. The rules governing cryptographic security in the Army and the Navy are based on the same doctrines and are, in general, similar, Compliance with the rules of either service should insure the necessary cryptographic security.
3. Classified communication between Army and Navy commands or units resolves itself into the following categories or echelons as regards distribution of cryptographic systems:

   Category A--Cryptographic systems used in communication between special high commands of the Army and Navy.

   Category B--Cryptographic systems used in communication between all high commands of the Army and Navy.

   Category C--Cryptographic systems used in communication between intermediate commands of the Army and Navy.

   Category D--Cryptographic systems used in communication between smaller units of the Army and Navy.

4. The foregoing categories should, in general, be followed, but may be varied, if necessary, at the discretion of the senior commander of either service in each theatre of operation. The senior commander of the other service shall be immediately notified.

5. The cryptographic systems prescribed for the various categories will be used as circumstances require. For this reason, all commands will be supplied with the cryptographic systems prescribed for lower categories.

6. The cryptographic systems authorized for safeguarding classified communication for each category are prescribed in the documents mentioned in paragraph 171a.

7. Only the prescribed cryptographic system shall be used for classified communication between the Army and the Navy.

8. Classified communication between Army and Navy units of categories A and B will be facilitated by an exchange of liaison and communication (signal) officers between the Army and the Navy elements involved.

170. [»] Grouping of Army and Navy units into categories for classified communication.--The categories authorized for classified communication, and the Army and the Navy units grouped therein, are as stated below:
     Category A.
     Army:
     War Department.
     Commanders, theatres of operations.
     Commanders, field armies.
     Any other commanders designated by the War Department.*
     Navy:
     Navy Department.
     Commanders-in-Chief, United States Navy.
     Any other commanders designated by the Navy Department.*
     1. Category B.
        Army:
        All commanders listed under category A above.
        Coastal frontier commanders.
        Commanders, expeditionary task forces.*
        Commanders, Hawaiian, Philippine, Panama Canal, and Puerto Rican Departments.
        Commander, troops in Alaska.
        Commanders, all corps areas.
        Commanders, GHQ Air Force and wings.
        Commanders, Air Corps wings in oversea departments.
        Commanders of major air fields likely to be engaged in joint operations.*
        Navy:
        All commanders listed under category A above.
        Force commanders, United States Fleet.
        Type commanders, United States Fleet.
        Commanding general, Fleet Marine Force.
        Commanders, major detached task forces, United States Fleet.*
        Commander, attack force.
        Commander, transport group.
        Commanders, detached squadrons.*
        Commanders, destroyer flotillas.
        Commanders, patrol wings.
        Commandants, all naval districts.
        Commanders, major naval air stations.*

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* The other Department will be informed of the commanders designated under this provision in order that all concerned may be notified.

3. Category C.
   Army:
   All commanders listed under categories A and B above.
   Commanders, coast artillery districts.
   Commanders, sectors (coastal frontier).
   Commanders, subsectors (coastal frontier).
   Commanders, harbor defenses.
   Commanders, shore parties.
   Commanders of units down to and including brigades which will communicate with Navy units.
   Commanders, Air Corps coastal stations likely to be engaged in joint operations.* Commanders, air force groups and squadrons.
   Commanders, ports of embarkation.
   Navy:
   All commanders listed under categories A and B above.
   Commanders, fire support group.
   Beachmasters.
   Destroyers, light mine layers, all larger combatant surface ships, and division and squadron commanders thereof.
   Squadron commanders of submarines, minecraft, and train vessels.
   Air squadron commanders.
   Commander, inshore patrol.
   Commander, inshore air patrol.
   Commander, offshore patrol.
   Commander, offshore air patrol.
   Commander, escort force.
   Commander, coastal force.
   Commanders, Fleet Marine Force brigades.
   Naval operating bases.
   Naval advanced bases.
   Naval air stations, air bases, and seaplane tenders.
   Destroyer, submarine, and section bases.

4. Category D.
   Army:
   All commands listed under categories A, B, and C above.
   Commanders of all mobile ground units down to and including infantry battalions and cavalry squadrons.
   Commanders, landing force combat teams.
   Commanders, individual forts or groups (harbor defenses).
   Army transports and mine planters.
   Aircraft in joint operations.

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* The other Department will be informed of the commanders designated under this provision in order that all concerned may be notified.

Navy:
All commands listed under categories A, B, and C above.
Vessels of inshore patrol and offshore patrol.
Aircraft of inshore air patrol and offshore air patrol.
Coastal force vessels and aircraft.
Escort vessels and aircraft.
All vessels and aircraft (not a part of or attached to the local defense forces) engaged in joint operations.
Commander, Marine Corps units down to and including battalions.
171. General instructions.

     1. The authorized cryptographic systems for the categories of classified communication, the distribution of the various systems and the effective publications governing their use are prescribed in the current editions of the following documents:

        Army: SIGNAN.
        Navy: CSP 817, 818, 819, 820.

     2. The communication (signal) plans should normally prescribe the cryptographic systems to be used.

     3. Whenever practicable, in joint tactical exercises or communication training exercises simulating coastal frontier defense, oversea expeditions and landing force operations, exercise or training editions of the prescribed cryptographic systems shall be used.

     4. For emergency use in peacetime by all categories of command, the cylindrical cipher device (Army: M-94; Navy: CSP 488) shall be used. A universal emergency key for use with this device shall be determined jointly by the Chief Signal Officer and the Director of Naval Communications and shall be communicated to both services from time to time. CIpher keys for use in local emergencies shall be determined locally and jointly by the senior commanders of the Army and Navy units involved. The United States Coast Guard holds this device and is furnished the universal emergency key by the Director of Naval Communications.

Subsection V--Joint Communication (Signal) Plan

(See ch. VI, sec. VIII, par. 108-110).

172. General.--The joint communication (signal) plans (or orders) for joint operations of the Army and the Navy (whether for coastal frontier defense or joint overseas expeditions) will in general include the following items, in the sequence indicated below:

     1. Information.

        1. Such information of enemy communication (signal) as may be essential from the point of view of joint operations of the Army and the Navy.

2. Such information of friendly commercial communication facilities as are to be used or are available for use) as may be necessary for the coordinated action of the two services in joint operations.

3. Such information of the communication (signal) systems of the two services as may be necessary for understanding by one service of the capabilities and limitations of the communication (signal) systems of the other service.

4. Such information of the aircraft warning service communication system as is necessary to insure the prompt reception and distribution of the information of approach of hostile aircraft.

5. Such information pertaining to the command "set-up" (i.e., location of the headquarters or command posts) of the two services as may be necessary for the effective installation and operation of communication (signal) system.

6. Designation of the time systems to be used for communication purposes and in the texts of messages.
2. Radio.

   1. General radio instructions, as necessary, including radio silence restrictions, etc.

   2. Call signs and frequencies, to include such instructions covering the assignment and distribution of radio call signs and frequencies as may be necessary--

      1. To insure coordinated action and avoid mutual interference between the two services.

      2. To provide a guide for the two services in distributing the particular items or publications to the interested elements of the two services.

      3. Time when call signs and frequencies become effective (see par. 172a(6)).

   3. Instructions for the establishment and operation of such special channels of radio communication as may be required for joint operations include--

      1. The assignment of personnel and special equipment when necessary.

      2. Operating schedules, etc.

   4. Authentication instructions.

3. Radio intelligence (radio direction finding and radio intercept)--include such information and instructions as to radio intercept and direction finding as may be necessary for--

   1. The coordinated action of the radio intelligence service of the Army and Navy.

   2. The distribution (or exchange) of radio intelligence.

4. Visual.

   1. General instructions, as necessary, including--

      1. Restrictions as to use of visual signal equipment, daylight and darkness.

      2. Priority of various means (flags, searchlights, etc.).

      3. Meanings of special pyrotechnic signals.

   2. Visual call signs.

      1. Call signs needed for communication between the Army and Navy.

      2. Guide for the distribution of call signs to interested elements of the two services.

      3. Designation of such visual codes as may be required for joint operations.

      4. Time when call signs are effective. (See par. 172a(6).)

   3. Instructions for the establishment and operation of such special visual channels as may be required between elements of the two services.

5. Wire.--Instructions necessary for the installation, operation, and maintenance of such wire communications as may be needed between the two services should include provisions for a wire teletype (telegraph printer) or telegraph antiaircraft intelligence net and an aircraft warning service net. (See Diagram I.) If required, authentication instructions should be issued.

6. Messenger (or courier) service.--Instructions necessary for the operation of a messenger service between Army and Navy elements when practicable and necessary, should state schedules, means of transportation, and whether officer or enlisted man.

7. Recognition signals.

   1. Recognition doctrine.

   2. List of the types to be used--day and night--with statements of time when each becomes effective.

   3. Guide for distribution.

   4. Identifying silhouettes of--
      Ships: Friendly and enemy.
      Aircraft: Friendly and enemy.

5. Recognition signals (surface craft, submarines, and aircraft)--
   Type or types to be used.
   Prescribed signals or maneuvers.
   Identifying marks on ships, special flags, lights, etc.
8. Communication security and cryptanalytic activities.--Such instructions should be promulgated as may be necessary to insure the coordination of the communication security activities of the two services and the prompt exchange of technical information between the cryptanalytic elements of the two services.

9. Codes and ciphers.

   1. Such instructions as are not included in existing regulations and publications concerning the codes, ciphers, and cipher keys to be used in joint operations.

   2. Guide to the distribution of codes and ciphers.

10. Commercial communication facilities.

    1. Such allocations to the Army and the Navy as may be required.

    2. Special instructions covering traffic to be handled by commercial stations.

    3. Special instructions covering supervision of commercial communication facilities.

    4. Call signs and frequencies.

Subsection VI--Miscellaneous

173. Other joint communication requirements.--In addition to the intercommunication necessitated by simulated or real joint coastal frontier defense and joint overseas expeditions, intercommunication may be necessary daily in peacetime for liaison purposes between various units of the Army and the Navy (and the Coast Guard), and when specially required in cases of earthquakes, flood, riot, and other emergencies, both natural and man-made. During neutrality, intercommunication may be necessary in the joint maintenance of a patrol in United States coastal waters. For the purposes indicated above, the doctrines set forth herein will, insofar as applicable, govern.

Table of Contents  ** Change No. 2 [missing]  * Change No. 4

Footnotes

1. Ch. IX--Revised and republished June 28, 1940. Section I of the revised Chapter IX is a republication of old Section A with a redesignation of the section. Paragraph numbering of old Section A, 1 to 9, is retained pending revision and republication of Section I. Section II is new matter replacing old Section B the contents of which is withdrawn from Joint Action of the Army and the Navy, 1935, and issued as a separate document under a "restricted" classification. Paragraphing in Section II begins with 156.