MARITIME UNIT
FIELD MANUAL -
STRATEGIC SERVICES
(Provisional)
Prepared under direction of
The Director of Strategic Services
OSB REPRODUCTION BRANCH 47189
MARITIME UNIT FIELD MANUAL
-STRATEGIC SERVICES
(Provisional)
Strategic Services Field Manual No.
Office of Strategic Services
Washington, D. C.
18 July 1944
This Provisional Basic Field Manual for Maritime
Unit is made available for the information and guidance
of selected personnel and will be used as the basic doctrine
for Strategic Services training for the operations of these
groups.
The contents of this manual should be carefully con-
trolled and should not be allowed to come into unauthor-
ized hands. The manual will not be taken to advance bases.
AR 380 — 5, pertaining to the handling of secret docu-
ments, will be complied with in the handling of this
manual.
William J. Donovan
Director
TABLE OF CONTENTS _ ... c ^
SECTION I— INTRODUCTION
1. SCOPE AND PURPOSE OF MANUAL . . . 1
2. DEFINITIONS 1
SECTION II— OPERATIONS AND METHODS
3. MISSIONS 2
4. CLANDESTINE FERRYING 2
5. MARITIME SABOTAGE 3
6. MILITARY TACTICAL ASSISTANCE ... 3
7. SPECIAL TRAINING BY MU 3
8. EQUIPMENT 4
SECTION III— ORGANIZATION AND PLANNING
9. BRANCH AND FIELD BASE ORGANIZATION 4
10. PLANNING AND ORGANIZATION FOR
OPERATIONS 5
SECTION IV— PERSONNEL
11. REQUIREMENTS 6
12. RECRUITING 6
SECTION V— TRAINING
13. BASIC TRAINING 6
14. SPECIALIZED TRAINING 7
APPENDIX "A"— EXAMPLES OF
TYPICAL MU OPERATIONS
1. INTRODUCTION 8
2. MARITIME SABOTAGE (1) 8
3. MARITIME SABOTAGE (2) 9
4. CLANDESTINE FERRYING (1) . . . . 9
5. CLANDESTINE FERRYING (2) .... 10
6. CLANDESTINE FERRYING (3) .... 10
(Provisions^ 9 fe t3
SECTION I— INTRODUCTION
1. SCOPE AND PURPOSE OF THE MANUAL
This manual sets forth the authorized functions,
operational plans, methods, and organization of Maritime
Units (MU) as a part of OSS operations. Its purpose is to
guide Strategic Services personnel responsible for plan-
ning, training, and operations in the proper employment
of Maritime Units.
2. DEFINITIONS
a. Over- All Program for Strategic Services Activi-
ties — a collection of objectives, in order of priority (im-
portance) within a theater or area.
b. Objective — a main or controlling goal for accom-
plishment within a theater or area by Strategic Services
as set forth in an Over-All Program.
c. Special Program for Strategic Services Activi-
ties — a statement setting forth the detailed missions
assigned to one or more Strategic Services branches, de-
signed to accomplish a given objective, together with a
summary of the situation and the general methods of
accomplishment of the assigned missions.
d. Mission — a statement of purpose set forth in a
special program for the accomplishment of a given
objective.
e. Operational Plan — an amplification or elabora-
tion of a special program, containing the details and
means of carrying out the specified activities.
f . Task — a detailed operation, usually planned in the
field, which contributes toward the accomplishment of
a mission.
g. Target — a place, establishment, group, or indi-
vidual toward which activities or operations are directed.
DECLASSIFIED
h. The Field — all areas outside of the United States
in which strategic services activities take place.
i. Field Base — an OSS headquarters in the field,
designated by the name of the city in which it is estab-
lished, e.g., OSS Field Base, London.
[. Advanced or Sub-base — an additional base estab-
lished by and responsible to an OSS Field Base, London.
k. Operative — an individual employed by and re-
sponsible to the OSS and assigned under special pro-
grams to field activity.
1. Agent — an individual recruited in the field who is
employed and directed by an OSS operative or by a field
or sub-base.
m. Parent Craft — the medium by which personnel
and supplies are transported from the base to within
Maritime Unit operational distance of their objective.
SECTION II— OPERATIONS AND METHODS
3. MISSIONS
a. To conduct clandestine ferrying.
b. To conduct maritime sabotage.
c. To provide military tactical assistance.
d. To conduct special training by Maritime Unit.
4. CLANDESTINE FERRYING
a. General — Penetrations into and departures from
enemy areas by water will be the specific responsibility
of MU. The responsibility essentially will be to effect
the transfer of personnel, supplies, and communications
from water to land and land to water. Such ferrying
which will normally be clandestine may be considered
in two stages: approach and departure by parent craft,
transfer to and from parent craft.
b. Approach to Enemy Shore — This can be by a
parent craft of sufficient range and other characteristics
necessary to get within small boat or swimming distance
of enemy shore. Parent craft may be submarine, de-
I * £ % '.: f
craft may oe oTetaflfed^yJD'S.lN^
forces either for specific tasks or regular operations.
Parent craft may also be native or other vessels ac-
quired by OSS.
c. Transfer op Personnel and Materiel to and from
Parent Craft to Shore — This may be by swimming,
surfboard, rubber boat, dinghy, or other small surface
craft.
5. MARITIME SABOTAGE
Maritime sabotage against enemy shipping and ship-
ping installations in harbors, roadsteads, canals, and
rivers, will be executed with limpets and other special
underwater demolitions and with standard demolitions.
Special Maritime Groups of swimmers are trained to con-
duct underwater sabotage. However, MU personnel will
also participate in maritime sabotage by ferrying demoli-
tions parties to targets or target areas.
6. MILITARY TACTICAL ASSISTANCE
a. General — Where unique techniques and abilities
of MU (such as underwater approach and clandestine
ferrying and maritime sabotage) are required by a mili-
tary commander in his theater, such aid by MU shall
be furnished as requested of OSS by the theater com-
mander.
b. Special Tactical Aids — MU sections, when ade-
quately manned at the theater base, may render
the following clandestine aid to military operations:
(1) hydrographic and beach reconnaissance; (2) estab-
lishing navigation aids, especially close to shore; (3) in-
filtration and exfiltration of personnel.
7. SPECIAL TRAINING BY MARITIME UNIT
a. General — MU will assist Schools and Training
Branch by providing instructors and equipment for the
training of other OSS personnel and military personnel
in special MU techniques, upon request.
b. OSS Personnel — Where operatives or agents have
to beinfiltrated or exfiltrated by water, they will be
_ DECLASSftlED
trained (usually in s ;t^e tjaeater) by S&T to enable them
to effect the transition from water to shore and vice
versa. MU will provide instructors and equipment to as-
sist in such training. Other MU techniques will be
taught to OSS personnel of other branches as required
for their special tasks.
c. Military Personnel — Where specific MU tech-
niques and equipment are of special use to military
commanders in their theater and where training in MU
techniques is requested by the military commander
through OSS, the MU Section in the theater will pro-
vide instructors and equipment to assist S&T in such
training.
8. EQUIPMENT
a. Specially designed equipment for use under water
and on the surface includes self-contained breathing
devices, motor propelled surfboards, swim suits, swim
fins, two and eight place kayaks, depth gauge, under-
water luminous compass, underwater flashlight, electric
waterproof motor for use on surf boards and rubber
boats. Detailed descriptions of this special equipment
are given in a secret pamphlet "Underwater Operations"
prepared for the Maritime Unit, December 1943.
b. Standard military and OSS demolitions are used.
A principal type is the limpet; the OSS magnetic type
and the "pin up" limpet. Military equipment and sup-
plies, such as rations, clothing, small arms, ammunition,
and the like will be supplied from U.S. Army or Navy
sources in the theaters. Special OSS explosives and
equipment will be supplied by Services Branch, OSS.
SECTION III— ORGANIZATION AND PLANNING
9. BRANCH AND FIELD BASE ORGANIZATION
a. Washington — The Chief of MU Branch, Washing-
ton, is directly responsible to the Deputy Director, SSO
for the carrying out of MU operations. He is assisted by
a Deputy Chief, an Operations Officer, a Supply Officer,
and a Personnel Officer. Liaison in Washington with
ip ^ | h ^ #^ |F| 1 J" 1 p ffc t
through appropriate officers of that nation in contact
with the Chief, MU, or any representative designated
by him.
b. Organization of Field Bases —
(1) The organization of MU at OSS field bases will
vary in accordance with local conditions and require-
ments, but generally they will reflect the structure of
the MU Branch, Washington.
(2) The MU Section of an OSS field base is headed
by a Chief who is responsible to the Strategic Services
Officer.
(3) The Operations Officer of the MU Section of
an OSS field base is responsible for planning and co-
ordination of operations with naval vessels detailed
to OSS tasks. In the case of naval units, they will be
administratively and operationally under the Navy.
(4) All activities of a field base in a theater of
operations are under the control and direction of the
theater commander.
10. PLANNING AND ORGANIZATION FOR OPERA-
TIONS
a. The approved OSS over-all and special programs
establish the objectives and missions for MU. Opera-
tional plans are developed by MU in the field in con-
formity with the approved special programs.
b. The MU section in the field assembles personnel
and equipment required to accomplish specific missions
based upon operational plans developed in accordance
with approved special programs.
c. All MU plans and operations are coordinated with
the activities of other branches by the Chief of the MU
Branch in Washington, and by the Chief of the MU sec-
tions at the various field bases. MU advises and assists
other branches on any project with maritime phases.
d. MU Branch in Washington is to be kept fully in-
formed of all MU plans and projects for operations
originating in the field.
SECTION IV— PERSONNEL
11. REQUIREMENTS
a. The duties of personnel selected for MU activities
divide into four general types:
(1) Staff work at the branch in Washington or in
the MU Section at a field base.
(2) Assisting S&T in instruction in special MU
techniques.
(3) Maritime operations.
(4) Special underwater swimming activities.
b. For all of these types of activities personnel should
be such that the MU special training can be assimilated
and employed effectively. For the first three types of
duties it is important that the personnel have seafaring
experience, particularly with small boats. For the special
underwater swimming activities, exceptional swimming
ability is a specific requirement.
c. The principal sources for the types of personnel
required for MU activities are the U. S. Navy, Marine
Corps, and Coast Guard. Competent personnel with
special skills are also taken from the Army and civil life.
12. RECRUITING
Personnel for MU activities is secured through the
regular OSS channels. Requests for personnel are sub-
mitted to the OSS Personnel Procurement Branch. This
branch makes all arrangements for procuring Army and
civilian personnel and forwards requests for Navy, Marine
Corps, and Coast Guard personnel to the Naval Command,
OSS.
SECTION V— TRAINING
13. BASIC TRAINING
a. The basic training for all MU personnel includes
the following subjects:
(1) Day and night landings (and reembarkations)
through surf.
(2) Swimming in surf and under water.
(rubber boats, kayaks, caiques, etc.)
(4) Navigation, piloting, seamanship.
(5) Reading of maps, charts and aerial photo-
graphs.
(6) Hydrographic and beach reconnaissance.
(7) Maritime sabotage instruments and methods.
(8) Harbor and beach defenses.
(9) Demolitions.
(10) Small arms (sub-machine guns, pistol, car-
bine, rifle, MG) .
(11) Operation and simple maintenance of out-
board and marine motors.
(12) Operation and care of special MU underwater
and surface gear.
(13) Signaling.
(14) Hand-to-hand combat.
(15) Types and designs of ships.
(16) Geography of area of operations.
b. For all types of MU personnel recruited in the U. S.,
basic training in all subjects is given in the U. S.
c. Personnel recruited overseas are given basic train-
ing and specialized training at field schools established
in the various theaters.
d. MU instruction for special courses in MU tech-
niques is made available especially in the field to other
branches of the OSS and on request to military and naval
personnel not assigned to OSS.
14. SPECIALIZED TRAINING
a. "Operational Personnel" are specially trained and
equipped for special duties such as clandestine ferrying,
maritime sabotage, and military tactical assistance.
Such advanced training is normally given by MU in-
structors at field bases.
b. "Special Maritime Groups" of swimmers are given
intensive training in underwater swimming (normally
a minimum of six months). They are organized and
trained specifically for underwater operations and there-
fore should be used only for tasks for ^jfljgfa^his special
trainii
DECLASSIFIED
APPENDIX "A"
EXAMPLES OF TYPICAL MU OPERATIONS
1. INTRODUCTION
No attempt is made herein to assess the reasoning
and considerations which must precede the assignment of
a task to a particular section of an OSS Field Base. This
Appendix will serve to illustrate several typical Maritime
Unit operations.
2. MARITIME SABOTAGE (1)
a. Problem — It is desired to attack an enemy vessel
moored in the channel of a hostile harbor.
b. Solution — Task is assigned to Maritime Unit Sec-
tion of OSS Field Base, since weighing of all factors
concerned indicates that underwater sabotage attack
presents greatest likelihood of success.
(1) Personnel
Since underwater swimming is required, two
Special Maritime Group (SMG) men are assigned
the task.
(2) Method of Attack
It is planned that one man will affix limpets
to the side of the vessel, while the other will secure
plastic charges to the fore and aft anchor cables. Use
of lungs, swim suits, depth gauges, compasses and
fins is required.
(3) Penetration of Harbor
(a) This is executed by parent craft (sub-
marine, or surface vessel, depending upon circum-
stances assigned by Theater Commander) which
transports the SMG men to
(1) Rendezvous point where friendly na-
tive fishermen may pick them up, secrete them,
take them into harbor and return them to
rendezvous point after they had finished af-
fixing explosives with twelve - hour, time
charge
over the side in inflated surfboard. This would
be used to take the men within underwater
swimming distance of target, then deflated,
secured perhaps to a channel marker so that
it may be regained, reinflated by special C0 2
bottle and used to rendezvous with parent
craft on return, or
(3) Within actual underwater swimming
distance of the target.
3. MARITIME SABOTAGE (2)
a. Problem — It is desired to destroy an important
lock (or dock, or bridge) in an enemy canal. Heavy
guard prevents approach from shore.
b. Solution — Task is assigned to MU Section of OSS
Field Base, as underwater approach appears to be only
reasonably safe method of attempting attack.
(1) Personnel
An MU operative (trained as member of Spe-
cial Maritime Group), thoroughly conversant with
the locality, language, customs of the natives and
highly trained in demolition, work is selected.
(2) Method of Attack
Attack will be made under water and will re-
quire the use of lungs, fins, swim suits, gauges, com-
pass and the handling of explosives and fuses under
water.
(3) Penetration
Operative is parachuted into locality with his
equipment.
4. CLANDESTINE FERRYING (1)
a. Problem — It is desired to land an OSS Operational
Group on a hostile beach so that they may penetrate
inland to contact guerrilla forces.
b. Solution — The task of ferrying is assigned to the
A group of ten OG's is turned over to the
Maritime Unit for several days intensive training in
landing through surf. Four Maritime Unit men are
assigned responsibility for delivery of OG's.
(2) Approach
A suitable parent ship is assigned to this par-
ticular task. It transports the OSS men to within
several hundred yards off shore of landing point on
beach under cover of darkness. Two 8-man kayaks
are assembled and put over the side. In each are two
MU men, five OG's and equipment. The OG's are
landed after one MU man has gone over the side and
swum in to assure that reception committee of guer-
rillas with whom rendezvous has been established are
on hand and that landing has been made at correct
point. Similar technique is followed to evacuate per-
sonnel from beaches.
5. CLANDESTINE FERRYING (2)
a. Problem — It is desired to land two native SI agents
in an enemy port.
b. Solution — Task of ferrying is assigned to Mari-
time Unit Section of OSS Field Base.
(1) Personnel
One MU operative, operating under cover as
a native fisherman is assigned responsibility for task.
(2) Method of Penetration
The MU operative is in command of a felucca
with a reliable crew of natives. This vessel regularly
engages in off shore fishing and delivers catch into
nearest port, village or harbor every several days.
This craft delivers the two SI agents directly into port
of their objective, all personnel concerned being under
cover as natives.
6. CLANDESTINE FERRYING (5)
a. Problem — It is desired to establish communica-
tions with partisan groups on a coastal island which
must be approached through enemy-controlled waters.
The purpose is to supply them continuously with arms,
ammunition, food and medicines.
b. Solution — Task is assigned to Maritime Unit Sec-
tion of OSS Field Base.
(1) Personnel
The MU section has trained a number of na-
tives to act as crews for native caiques with under
cover MU operatives as commanding officers. Three
such vessels with crews are assigned responsibility.
(2) Method
Under cover as fishing boats and native ferries,
these vessels accomplish their assigned mission by
continuous ferrying of supplies to objective.
11