Created: 6/1/1962

OCR scan of the original document, errors are possible


TITLE: echnique For Coastal Infiltration

AUTHOR: John A. Hurley




A collection ol Articles on Ihe historical, operational, doclrlnal, ond ihooroiical aspects ol inlolligonco.

Alt statements of fact, opinion or analysis expressed in Studies in Intelligence are those of

the authors. They do not necessarily reflect official positions or views of the Central Intelligence Agency or any oiher US Government entity, past or present. Nothing in the contents should be construed as asserting or implying US Government endorsement of an article's factual statements and interpretations.

A submarine escape procedure applied to clandestine



The various means of agent infiltration lntoa target area-overland travel, parachuting from or landing* inmall boat or kayak, swimming from ahave their disadvantages. Controls on overland travel usually render It more difficult than entry by air or water. The use of an airplane cither for parachuting or for landing, however. Is often contralndicated by the likelihood of detection and the difficulty of making an accurate blind drop or landing. On the coast, radar and sound detection networks make the userawler, HTB. or surfaced submarine dangerous not only for the agent but for his transporters. The hulkurfaced submarineubstantial radar return.ostile coast, moreover, faces the hazards of mine fields, nets, and chance encounters with naval or commercial small craft

Buoyant Ascent

One technique which circumvents some of these difflculUes Is that of buoyant ascentubmerged submarine, wherein the agent makes his exit from the submarine's escape chamber without any kind of breathing apparatus and isto the surfaceateeet per minuteMae West" Inflatable life jacket This method is conditioned by the contraction of gases under pressure In accordance with Boyle'sbreathed under pressureereeet down will double in volume at thethe consequent danger of lethal aerocinbolism upon ascent The agent must therefore exhale continuously on his way up.

The procedure Isimple one. The agent enters the escape chamber, and while its pressure Is being equalized by incoming air and water to that of the surrounding water, he breathes the Increasingly compressed air. During this time the life jacket Is also inflated, cither orally or from a


pressure outlet. When the pressure has been equalized,is opened and he climbs out. He looks to theextends his arm to maintain his posture, and heduring the ascent. Air expansion in the lifetaken care ofleeder valve which allows theto escape Into the water. Once on the surface,can be used to buoy the agent and his gear.

separate floats with connecting lines to facuita.Je.4tsthe

If It is inadvisable lor the agent to show himself on the surface near the coast, swimming oringhy, he can be equipped with the self-contained underwater breathingScuba, to enable him to stay under. For use near the surface there Islosed-circuit Scuba which makes no exhaust noise and leaves no telltale bubbles (butazard of oxygen poisoning when used at depths greater thaneet).

The exflltration of an agent can be accomplished bythe process. If he is equipped with Scuba, the re-entry Into the submarine's escape chamber presents no difficulty.ree swimmer it might beeat, but Scuba divers from the sub could help him. Emergency contact with the submarine could be madecuba-equipped agent bydown and banging on the hull, and without Scuba, in extremity, by dropping very small underwater signal charges.umber of agents were to be evacuated, it might be best, particularly if they lacked Scuba, for the sub to use itsto snag and tow themurface lineoint where it could surface or an amphibian could land.

Training Jot Escape

The buoyant ascent technique has been developedeans of escapeisabledhe earliest escape devices were re-breathers of. Momsen Lung, the German Draeger, the British BSSA. The United States, in particular, also set great store by the rescueressure chamber travelingable that

'The fascinating history of submarine escape Is comprehensively presented by Commander W. O. Shelford In Substtnk.

would lockisabled sub, receive Its crew, and transport them to the rescue vessel.

The pattern of World War H's successful submarineas they were, favored freerocedure likeascent butife Jacket to speed thechief disadvantage Is the difficulty of correlating theascent with the rate of exhalation. Too muchresult ta^drownlng, tco^Httle; lnhe

correlating maxim "No faster than your smallest.bubblc"always be followed wider stress or ln murkyree swimmer at depth might also not head straight for surface.

herefore, buoyant ascent became the standardescape method of the United States Navy. Recruits are trained (at New London) and personnel requalined (at New .London or Pearl Harbor) by practical exercisesoot escape tower. Before being put through these runs in the tank, they are testedressure chamber to make sure that they can adjust to the equivalenteet ofounds per square inch, as opposed7 at seahen there are several hours of class-room and mock-up work before the trainees are taken to the top of the tank, where they begin with shallow ascents to practice the

Finally they are tested in ascents fromfoot depth. With an Instructor, about ten of them enter an "escape" chamber at that depth. The instructor equalizes the pressure with that in the tank by flooding and admitting air, and the occupants "equalize" as the pressure builds up. Then the hatch swings open, and each trainee In turn Alls his life jacket, breathes deeply, and steps out into the tank. Scubawatch bis bubble stream toa safety measure and for purposes ofhe Is exhaling Two successful runs are required for qualification.*

ew device for buoyant ascent from greater depths has been developed and tested by Lt. Harris SMlnke and his staQ at Ihe escape tower. Itood attached to the top of the life jacket which captures air vented from the Jacket under decreasing pressure so that the escapee can breatheong ascent. The Sleinke hood has been tested In trial runseet off the Dry Tortugss.


The psychological assurance and real value gained fromof the buoyant ascent technique are out of allto the onealf days spent in training forescape, and it should be an equally good bargain in Its promising applications to clandestine operations.

Original document.

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