Francais | English | Espanõl

Frogman

From Wikipedia, the free encyclopedia

(Redirected from Frogmen)
Jump to: navigation, search

Contents

This page describes a type of scuba diver. For other uses of the word frogman, see Frogman (disambiguation)

Frogman is a popular term for a scuba diver. The word arose around 1940 from the appearance of a diver in shiny wetsuit and with large fins on his feet. The term preferred by scuba users is 'diver', but the word "frogman" persists in usage by non-divers, especially in the media, often to refer to professional scuba divers in organizations such as the police.

Usual usage of the word "frogman" also tends to imply diving for action, often in combat; such divers are also sometimes called combat diver or combat swimmer.

A few sport diving clubs have included the word "Frogmen" in their names.

In the US Military, divers trained in scuba or CCUBA who deploy for military assault missions are called "combat swimmers". This term is used to refer to the Navy SEALs, the Marine Recon swimmers, the Army Ranger swimmers, and the Navy Explosive Ordinance Dispoal (EOD) units.

In Britain, police divers have often been called "police frogmen". The first British police diver was a policeman who, needing to search underwater for evidence or a body, did not use a drag but went home and fetched his sport scuba gear. See also Ian Edward Fraser.

Some countries' frogman organizations include a translation of the word "frogman" in their official names, e.g. Denmark's "Frømandskorpset" and Norway's "Froskemanskorpset"; others call themselves "combat divers" or similar. Others call themselves by indefinite names such as "special group 13" and similar.

Many nations and some irregular armed groups use or have used combat frogmen.

[edit] Defending against frogmen

See anti-frogman techniques for details of detecting and combatting unwelcome frogman and scuba diver incursions.

[edit] Types of armed-forces divers

Military diving is a branch of professional diving carried out by armed forces. They may be divided into:-

These groups may overlap, and the same men may serve as assault divers and work divers, as in the Australian Clearance Diving Team (RAN).

[edit] Frogman training

Training armed forces divers, including combat divers, is far harder, longer, and more complicated than civilian sport scuba diver training, typically takes several weeks full-time, and the trainees must be at full armed forces fitness and discipline at the start. It needs much higher levels of fitness, and during the course there is often a high elimination rate of trainees who do not make the grade. For more details see the articles on each nation's frogman group below and their external links.

This contrasts with civilian sport scuba diving training which tends to be one evening a week, being 30 to 60 minutes swimming pool time, followed by two hours or so of dry meeting (often in a social-club-type environment with an open bar[citation needed]). The general environment at sport dives is liable to encourage what a naval diver-trainer would call "a casual tourist-type attitude to being underwater", rather than a disciplined attitude of obeying orders and not being distracted; some naval diver-trainers prefer, or will only accept, trainees who have no previous scuba diving experience. [1]

For example, the PADI Open Water Diver (the most basic rank) course takes 5 dives in a swimming pool and 4 dives in open water (i.e. sea, lake, etc.); after the course he is allowed to dive to 18 meters = 59 feet depth. The next step (Advanced Open Water Diver) allows him to dive to 30 meters = 98.425 feet, which is considered safe for civil scuba diving.

[edit] Equipment

For scuba diving gear in general, see Scuba set.

[edit] Breathing sets

Image:MDK dykker 370 17268a.jpg Frogmen's breathing sets on covert operations generally have these features:

  • It should be a rebreather, because:
    • Open-circuit scuba produces large amounts of bubbles and noise (both on exhalation, and the intake hiss of the regulator valve as the diver breathes in) showing where the diver is.
      • There have been experiments with making released air or gas come out through a diffuser, to break the bubbles up; this may sometimes work with the small amounts of gas that are sometimes released by rebreathers, but open-circuit scuba releases so much gas at every breath that a diffuser large enough to handle it without making breathing difficult would be too bulky and would interfere with streamlining.
    • Rebreathers give much longer dive times for the same size of breathing set.
  • It should be fully closed-circuit, not semi-closed circuit sets that emit a small but steady trail of bubbles, unless it has a diffuser on its blowoff vent.
  • It should be as silent as possible in use.
  • It should have a full face diving mask to let frogmen communicate underwater.
  • It should be a dull color to avoid being seen from out of the water. Many are black, but the Russian IDA71's backpack box is mostly dark green. No large bright-colored badges or manufacturer's logos.
  • It should contain as little iron or steel as possible, to avoid detection by magnetic sensors. This is also useful when the frogmen have to remove or defuse mines underwater.
  • It should be well streamlined, and small as possible for the dive duration, for long fast swimming. With a combat diver this may mean removing safety features such as an open-circuit bailout that would add bulk.
  • It should have a long dive duration.
  • It should have the front of the frogman's abdomen clear so he can easily climb in and out of small boats or over obstacles, particularly out of the water.
  • Its breathing bag should be toughened against stabbing and scratches, or safely inside a hard backpack box.
    • Older Siebe Gorman-type rebreathers (see Siebe Gorman CDBA) had one breathing tube, which was in front of the chest and easier for the frogman to keep track of.
    • USA frogmen's rebreathers tended to have the breathing bag on the back before enclosed backpack-box rebreathers became common.

Link to French Wikipedia image of frogman with "Oxygers" rebreather

[edit] The Russian IDA71

The Russian IDA71 military and naval rebreather is a typical frogman set:

  • Its backpack casing is hard smooth rounded metal and has little that can be easily grasped and pulled at. There is no mass of projecting valvework behind his neck to cause hydrodynamic drag and for an attacker to grasp.
  • Its only external control is its on/off switch, which is on its right edge near the bottom where he can reach it easily.
  • It does have looping breathing tubes like an old-type aqualung, but these originate well apart next to where they come over his shoulders and do not have to reach across from the back of his neck. They can be strapped to the shoulder straps so they do not float up into big vulnerable loops behind the shoulders.
  • When the frogman comes out of water quickly, the holes in the casing let contained water drain quickly, so he is quickly rid of the weight of that water.

[edit] Open-circuit scuba

The common sport open-circuit scuba set is not recommended for combat action:

  • The duration of open circuit is shorter than most rebreathers.
  • The bubbles released by open circuit SCUBA increase likelihood of mission compromise.
  • The long trailing regulator hoses are easily fouled.
  • It makes the diver heavy and cumbersome in rolling over and changing course or speed.
  • The noisy bubbling and regulator intake hiss make it difficult to approach underwater unheard, unless the frogman holds his breath, which is not recommended and extremely risky: see diving hazards and precautions.

Combat frogmen often use open-circuit scuba sets during training and for operations where observation or long distance swimming are not significant concerns.

Some rebreather rigs (mixed gas) are heavier than standard double tank open circuit SCUBA, particularly if burdened with an open-circuit baleout, as often in sport technical diving rebreathers; but armed forces rebreathers tend to be more compact. Other rigs, like the Draeger, are lighter. The rebreathers which are the most compact in proportion to dive duration are oxygen rebreathers, which are depth limited to about 8 meters = 26 feet due to the oxygen toxicity risk.

[edit] Breathing sets in diver-against-diver combat

Underwater combat between opposing teams of "frogmen" is common in fiction (as in the movie "Thunderball", and at least one incident in Sea Hunt, and often in comics), but rare in reality. But there have been instances of diving sea-police arresting civilian divers for illegal spearfishing and diving in restricted areas and the like, and of naval divers being sent down to investigate unidentified divers in a naval harbour. Thus any consideration of the gear for "diver to diver combat" is less important when designing an selecting the equipment.

A principal reason why divers are rarely sent against divers is that most harbors and similar waters have fairly limited visibility. The hope of sending a diver down to find a moving diver who does not wish to be found is highly limited. For this reason, in combat, other methods are generally used. Occasionally in law enforcement, where the suspect diver is not likely to know combat techniques, and the water is clear enough or it is well known where the suspect diver is, police or ared forces divers are sent to retrieve or arrest suspect divers.

But the point is considered here for completeness. The common sport open-circuit scuba set is not recommended for a fight against a trained naval or combat diver, because:-

  • In any sort of underwater combat, a man with a large aqualung has a high rotation-inertia and is very unstreamlined in the twisting and turning involved in fighting and straight swimming, and his maneuvering is slowed critically compared to a man with a light streamlined rebreather with all parts close to his body. Its working parts and breathing tube or tubes should be safe from attack in an underwater fight, including in the risk of being "jumped" from above.
  • Turning the air off or on is easy for an attacker from above but difficult or impossible for the frogman himself, unless the cylinder or cylinders are mounted inverted. However, that needs more pipework, and it is easy to bump the valvework on things when taking the set off.
  • The long trailing breathing tubes or regulator hoses can easily be grasped and pulled.
  • See full face diving mask for information about masks in case of risk of underwater fights.

[edit] Masks

Most frogmen use a full face diving mask instead of separate mouthpiece and mask. The older type of British frogman's and naval diving mask was full face and had a mouthpiece inside it. Some frogmen use a mouthpiece and noseclip or a mouth-and-nose (oro-nasal) breathing mask instead of a diving mask with eye windows, and special contact lenses to correct the vision refraction error caused by the eyeballs being directly submerged. This is to avoid a searchlight or other lights reflecting off the mask window and thus revealing his presence, but it exposes the eyeballs to any pollution, poison, or organisms in the water.

The United States military has adopted Oceanic/Aeris's "Integrated Diver Display Mask". It is a basic "Heads-Up Display" that lets divers monitor depth, bottom time, tank pressures, and related information while leaving their hands free for other tasks.

[edit] Fins

Another problem with a frogman who may have to come ashore and operate on land is the awkwardness of walking on land in fins, unless he plans to discard his kit and return to base by some other way than by diving, or if the frogmen plan to take and hold a position on land until other troops arrive. Some sport diving fins have the blade angled downwards for more effective swimming, but this makes walking on them more awkward.

The usual solution is for the frogman to take his fins off and carry them, but that takes time and occupies a hand carrying them unless he can clip them in to his kit or thread an arm through the fins' straps.

Another type of fin that frogmen could use would have a lockable hinge which on land can be unlocked to let the fin blade hinge up out of the way when walking.

The first type of British naval swimming fin had a short blade which was even shorter at the big toe side: this made walking on land easier for such purposes as creeping up on a sentry from behind on land, but reduced swimming speed.

[edit] Diving suits

The frogman's diving suit should be a tough scratch-and-cut-resistant drysuit (perhaps reinforced with kevlar), and not a soft foam wetsuit. A wetsuit can be worn under the drysuit as a warm undersuit. In very warm water, a thin tough drysuit can be worn with no undersuit.

It should not have obvious bright colored patches, unit badges or the suit's maker's advertising. Diving sea-police types, however, may find that a unit badge is useful.

[edit] Tools and weapons carried underwater

Weapons that can be carried by a frogman include:

[edit] Transport for frogmen

Frogmen may approach their site of operation and return to base in various ways including:

  • Swimming all the way.
  • Canoes.
  • Being dropped off and/or picked up by fast Rigid-hulled inflatable boats.
  • In World War II, Italian and British frogmen used manned torpedoes to carry them to their targets. Some nations still keep manned torpedoes.
  • The Subskimmer and similar.
  • Midget submarines such as the X-craft, the SDV or the US Advanced SEAL Delivery System ASDS which frogmen can exit and return to through an airlock.
  • Full-sized submarines which frogmen can exit and return to, sometimes through a special airlock or through one of the sub's torpedo tubes. These two methods, like all methods, need precautions: this link (in Russian) describes a risky incident in diving from a submerged submarine: the sub was neutrally buoyant at the start, and the first frogman airlocking changed the sub's buoyancy, and the sub started to float up; in later dives the sub's captain ballasted the sub well to keep the sub on the seabed while frogmen were coming out or in.
  • More powerful versions of sport-diving diver-tugs. Unmodified sport-diving diver-tugs are usually not powerful enough or not long enough duration on a battery recharging.
  • The Protei 5 and similar. See Diver Propulsion Vehicle.
  • Some frogmen are trained to parachute in to their site of operation. The backpack box of the Russian IDA71 frogman's rebreather has two metal clips to fasten to a parachute harness.

[edit] Types of frogman operations

  • Amphibious assault: stealthy deployment of land or boarding forces. The vast majority of Combat Swimmer missions are simply to get "from here to there" and arrive suitably equipped and in sufficient physical condition to fight on arrival. The deployment of tactical forces using the arrival by water to assault land targets, drilling platforms, or surface ship targets (as in boardings for seizure of evidence), is a major driver behind the equipping and training of combat swimmers. The purposes are many, but include feint and deception, anti-drug, law enforcement, anti-terrorism, and anti-proliferation missions.
  • Sabotage: This includes putting limpet mines on ships.
  • Clandestine surveying: Surveying a beach before a troop landing, or other forms of unauthorized underwater surveying in denied waters. The article "Riding on Proton" by Afonchenko (in Russian) may describe in passing a Soviet Bloc frogman infiltration into South Korean sea.
  • Clandestine underwater work, e.g.:-
    • Recovering underwater objects.
    • Clandestine fitting of monitoring devices on underwater communication cables in enemy waters.
  • Investigating unidentified divers, or a sonar echo that may be unidentified divers. Diving sea-police work may be included here. See anti-frogman techniques.
  • Checking ships, boats, structures, and harbors for limpet mines and other sabotage; and ordinary routine maintenance in war conditions. If the inspection divers during this find attacking frogmen laying mines, this category may merge into the previous category.
  • Underwater mine clearance and bomb disposal.

[edit] Mission descriptions

The U.S. and UK forces use these official definitions for mission descriptors:-

  • Stealthy - Keeping out of sight (e.g. underwater) when approaching the target.
  • Covert - Carrying out an action which the enemy may become aware of, but it cannot easily be discovered who or what did it. Covert action often involves military force which cannot be hidden once it has happened. Stealth on approach, and frequently on departure, may be used.
  • Clandestine - It is intended that the enemy does not find out then or afterwards that the action has happened. Installing eavesdropping devices is the best example. Approach, installing the devices, and departure are all to be kept from the knowledge of the enemy. If the operation or its purpose is exposed, then the actor will usually make sure that the action at least remains "covert", or unattributable: e.g. ("...the secretary will disavow any knowledge of your actions.")

[edit] Derivative word usages

  • Some scuba diving clubs have an entry class called "Tadpoles" for younger children who want to start scuba diving.
  • Royal Navy men have a slang term "pond life" to mean civilian sport divers.

[edit] Errors about frogmen found in public media

[edit] Wrong use of the word "frogman"

"A new English translation of the book Twenty Thousand Leagues Under the Sea" uses the word "frogman" uniformly and wrongly to mean a diver in standard diving dress or similar, to translate French scaphandrier.

[edit] Supposed ancient scuba divers/frogmen

Ancient Assyrian stone carvings show images which some have supposed to be frogmen with crude breathing sets. However, the "breathing set" was merely a goatskin float used to cross a river, and its "breathing tube" was to inflate it by mouth. See timeline of underwater technology.

[edit] Mistakes in fiction

[edit] Aqualungs

Many comics have depicted combat frogmen and other covert divers using two-cylinder twin-hose open-circuit aqualungs. All real covert frogmen use rebreathers because the stream of bubbles from an open-circuit set would give away the diver.

Many aqualungs have been anachronistically depicted in comics in stories set during World War II, when in reality aqualungs were unknown outside Jacques-Yves Cousteau and his close associates in Toulon in south France. Although some aqualungs were smuggled out of occupied France during the war (these may have been Commeinhes aqualungs), the aqualung for the most part was not a player in combat in World War II. The movie The Frogmen also made this mistake, using three-cylindered aqualungs. DESCO were making three-cylinder constant flow sets that lacked the demand valve of the aqualung, but they were rarely deployed in the war, the preferred system being the rebreather developed by Dr. Christian J. Lambertsen.

[edit] Drawing and artwork

There have been thousands of drawings (mostly in comics, some elsewhere) of combat frogmen and other scuba divers with two-cylinder twin-hose aqualungs shown wrongly with one wide breathing tube coming straight out of each cylinder top with no regulator, far more than of twin-hose aqualungs drawn correctly with a regulator, or of combat frogmen with rebreathers. See this image for the correct layout.

[edit] Movies and fiction

Frogman-type operations have featured in many comics, books, and movies. Some try to reconstruct real events; others are completely fictional. Some make mistakes as described above. See also:-

[edit] History

In ancient Roman and Greek times, etc, there were many instances of men swimming or diving for combat, but they always had to hold their breath, and had no diving equipment, except sometimes a hollow plant stem used as a snorkel. See the first part of the page at this link (in Portuguese).

The first known frogmen-type operations using breathing apparatus were by the Italian Decima Flottiglia MAS, which formed in 1938 and was in action first in 1940. See Timeline of underwater technology and each of the nations' frogman unit links below.

[edit] Nations with military diving groups

Italy started World War II with a commando frogman force already trained. Britain, Germany, the United States, and the Soviet Union started commando frogman forces during World War II.

[edit] Argentina

The Buzos Tácticos is Argentina's combat frogmen force.

[edit] Austria

See Austrian commando frogmen.

[edit] Australia

The Clearance Diving Team (RAN) is Australia's combat frogman and underwater work force.

[edit] Brazil

See Brazilian commando frogmen.

[edit] Britain

See:-

[edit] Canada

Canada has Clearance Divers in Fleet Diving Units, and trains some of them as combat divers as a sub-trade in its Army Combat Engineering Regiments. These combat divers are considered among the most skilled underwater operators in the world. They are trained in:-

They have a saying "Strength in depth".
There is a saying about them: "Once you see them, it's too late".

[edit] Denmark

See Danish Frogman Corps

[edit] Eritrea

During Eritrea's war of independence against Ethiopia, the rebel forces had a combat frogman force. After the war, some of those frogman were retrained as dive guides for the sport scuba diving tourism trade.

[edit] Finland

The Finnish Navy trains Finnish combat divers during a 362-day training period as it has since 1954. Applying for combat diver training is voluntary due to the rigorous training process, even though the Finnish Navy consists of compulsory military service as with the rest of the Finnish Defence Forces. An application for combat diver training does not necessarily guarantee entry to the training program, as the selection is as rigid as the training. The nature of the tasks that the Finnish combat divers may be ordered to carry out classifies them as commandos.

[edit] France

See French commando frogmen

[edit] Germany

See German commando frogmen

[edit] India

The MCU is the elite naval special operations unit of the Indian Navy that undertakes underwater combat. See MARCOS.

[edit] Indonesia

The TNI-AL/Indonesian Navy Underwater Combat Unit is called Kopaska.

[edit] Israel

It is reported that Israel's combat frogmen are among the most effective compared to their numbers and are said to have been in many operations. They started in 1948. See Shayetet 13.

[edit] Italy

See Italian commando frogmen

[edit] Malaysia

Malaysia has a special-forces naval unit called Paskal. It includes frogmen.

[edit] Mexico

See Fuerzas Especiales.

[edit] Netherlands

The Netherlands's Amphibious Reconnaissance Platoon is part of the Special Forces unit of the Royal Netherlands Marine Corps.

[edit] New Zealand

See http://www.navy.mil.nz/visit-the-base/rnzn-college/dive-school.htm . The New Zealand Navy trains all NZ Army, NZ Police, and NZ Customs divers. Military Dive Training support is also supplied to Singapore, Malaysia, Fiji, Tonga, and Samoa.

[edit] Norway

Norway's commando frogmen corps is called Froskemanskorpset = "the frogman corps". It is part of Marinejegerkommandoen = "the marine hunter command", which is something like the British SBS.

Norway has a clearance diver group called Minedykkerkommandoen = "the mine diver command".

[edit] Pakistan

Pakistan Army's SSG also has a unit in the Pakistan Navy modeled on the USA Navy SEALs: NSSG, otherwise known as SSGN. The SSGN currently has a headquarters in Karachi headed by Pakistan Navy Commander. It has a strength of one company and is assigned to unconventional warfare operations in the coastal regions. During war it is assigned to Midget submarines. All other training is similar to the Army SSG with specific marine oriented inputs provided at its Headquarters.

[edit] Philippines

For the Philippines' military frogman corps, see Special Action Force.

[edit] Portugal

See Destacamentos de Mergulhadores Sapadores

[edit] Russia

See Russian commando frogmen.

[edit] Tamil Tigers

The Sea Tigers (sea branch of the Tamil Tigers in Sri Lanka) have frogmen. See Sea Tigers#Frogmen

[edit] United States

The United States has several groups of combat divers:-

[edit] External links

de:Kampfschwimmer fr:Nageur de combat it:Sommozzatore zh:蛙人

Retrieved from "http://en.wikivisual.com/index.php/Frogman"
Personal tools