Frogman

This article is about a type of combat diver. For other uses, see Frogman (disambiguation).
A SEAL climbs aboard a SDV before launching from the back of the submarine USS Philadelphia.

A frogman is someone who is trained in scuba diving or swimming underwater in a tactical capacity that includes combat. Such personnel are also known by the more formal names of combat diver, combatant diver, or combat swimmer. The word frogman arose from Italian "uomo rana" around 1940 from the appearance of a diver in a shiny drysuit and large fins.

Combat swimming is often used to mean combat diving. Such actions are a historical form of "frogman" activity and an important feature of naval special operations.

The term frogman is occasionally used to refer to a civilian scuba diver. Some sport diving clubs include the word Frogmen in their names. The preferred term by scuba users is diver, but the frogman epithet persists in informal usage by non-divers, especially in the media and often referring to professional scuba divers, such as in a police diving role.

In the U.S. military and intelligence community, divers trained in scuba or CCUBA who deploy for tactical assault missions are called "combat divers". This term is used to refer to the Navy SEALs, operatives of the CIA's Special Activities Division, elements of Marine Recon, Army Ranger Regimental Reconnaissance Company members, Army Special Forces divers, Air Force Pararescue, Air Force Combat Controllers, U.S. Coast Guard Helicopter Rescue Swimmers, United States Naval Search and Rescue Swimmers, United States Air Force Special Operations Weather Technicians, and the Navy Explosive Ordnance Disposal (EOD) units. In Britain, police divers have often been called "police frogmen".

Some countries' tactical diver 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 "special operations unit".

Many nations and some irregular armed groups deploy or have deployed combat frogmen.

Scope of operations

Combat Camera Underwater Photo Team – A US Navy diver during underwater photography training off the coast of Guantanamo Bay, Cuba.

Tactical diving is a branch of professional diving carried out by armed forces and tactical units. They may be divided into:

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

The range of operations performed by these operatives includes:

Typically, a frogman with closed circuit oxygen rebreathing equipment will stay within a depth limit of 20 feet (6.1 m) with limited deeper excursions to a maximum of 50 feet (15 m) because of the risk of seizure due to acute oxygen toxicity.[1] The use of nitrox or mixed gas rebreathers can extend this depth range considerably, but this may be beyond the scope of operations, depending on the unit.

Mission descriptions

The U.S. and U.K. 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 of which the enemy may become aware, but whose perpetrator cannot easily be discovered or apprehended. 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".

Defending against frogmen

Anti-frogman techniques are security methods developed to protect watercraft, ports and installations, and other sensitive resources both in or nearby vulnerable waterways from potential threats or intrusions by frogmen.

Training

SEAL combat swimmer training

Training armed forces divers, including combat divers, is often harder, longer, and may be more complicated than civilian commercial or recreational scuba diver training. Training typically takes several months full-time, and the trainees must be at full armed forces fitness and discipline at the start. Even higher levels of fitness are generally required to successfully complete the training, and during the course there is often a high elimination rate of trainees who do not make the grade.

Equipment

For scuba diving gear in general, see Scuba set.

Breathing sets

Frogmen's breathing sets on covert operations should have particular features.

US frogmen's rebreathers tended to have the breathing bag on the back before enclosed backpack-box rebreathers became common.

Features needed

US Navy Explosive Ordnance Disposal dive equipment

A frogman's breathing set should:

Not open-circuit scuba

As a result, the frogman's breathing set should be fully closed circuit rebreather, preferably not semi-closed circuit and certainly not open-circuit scuba, because:

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

Breathing sets used by frogmen

Russian IDA71

The Russian IDA71 military and naval rebreather is typical of a back-mounted configuration suitable for use by frogmen:

Masks

Some frogmen use an ordinary diving mask; some use a fullface mask, which is less easily lost underwater. 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 (orinasal) 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.

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 into his kit or thread an arm through the fins' straps. Nowadays, all fins can be clipped onto a belt without having any disadvantages.

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: for example Flipfins.

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.

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.

For Bomb Disposal Operations, Canadian Naval Divers wear Bomb suits.

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.

Tools and weapons carried underwater

Weapons that can be carried by a frogman include:

Operational transport and delivery systems

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

History

A 1945 British navy frogman with complete gear, including the Davis apparatus, a rebreather originally conceived in 1910 by Robert Davis as an emergency submarine escape set.
A French frogman with chest counterlung loop rebreather with two breathing tubes (model "Oxygers", 1957).

In ancient Roman and Greek times, etc., there were instances of men swimming or diving for combat, sometimes using a hollow plant stem or a long bone as a snorkel. Diving with snorkel is mentioned by Aristotle (4th century BC).[3] The earliest descriptions of frogmen in war are found in Thukydides' History of the Peloponnesian War. The first instance was in 425 BC, when the Athenian fleet besieged the Spartans on the small island of Sphacteria. The Spartans managed to get supplies from the mainland by underwater swimmers towing submerged sacks with supplies. In another incident of the same war, in 415 BC, the Athenians used combat divers in the port of Syracuse, Sicily. The Syracuseans had planted vertical wooden poles in the bottom around their port, to prevent the Athenian triremes from entering. The poles were submerged, not visible above the sea level. The Athenians used various means to cut these obstacles, including divers with saws.[4] It is believed that the underwater sawing required snorkels for breathing and diving weights to keep the divers stable.[5]

The Hungarian Chronicon Pictum claims that Henry III's 1052 invasion of Hungary was defeated by a skillful diver who sabotaged Henry's supply fleet. The unexpected sinking of the ships is confirmed by German chronicles.

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.

First frogmen

The word frogman appeared first in the stage name The Fearless Frogman of Paul Boyton, who since the 1870s broke records in long distance swimming to demonstrate a new invented rubber immersion suit, which inflated hood had a frog-like shape. As a stunt show hero in that suit he played a military diver (attaching mines to ships etc.) long before such divers existed.

The first modern frogmen were the World War II Italian commando frogmen, of Decima Flottiglia MAS (now "ComSubIn": Comando Raggruppamento Subacquei e Incursori Teseo Tesei) which formed in 1938 and was first in action in 1940. Originally these divers were called "Uomini Gamma" because they were members of the top secret special unit called "Gruppo Gamma", which originated from the kind of Pirelli rubber skin-suit[6] nicknamed muta gamma used by these divers. Later they were nicknamed "Uomini Rana", Italian for "frog men", because of an underwater swimming frog kick style, similar to that of frogs, or because their fins looked like frog's feet.[7]

Italian frogman of "Gruppo Gamma"

This special corps used an early oxygen rebreather scuba set, the Auto Respiratore ad Ossigeno (A.R.O), a development of the Dräger oxygen self-contained breathing apparatus designed for the mining industry and of the Davis Submerged Escape Apparatus made by Siebe, Gorman & Co and by Bergomi,[8] designed for escaping from sunken submarines. This was used from about 1920 for spearfishing by Italian sport divers, modified and adapted by the Italian navy engineers for safe underwater use and built by Pirelli and SALVAS from about 1933, and so became a precursor of the modern diving rebreather.[9][10][11][12]

For this new way of underwater diving, the Italian frogmen trained in La Spezia, Liguria, using the newly available Genoese free diving spearfishing equipment; diving mask, snorkel, swimfins, and rubber dry suit, the first specially made diving watch (the luminescent Panerai), and the new A.R.O. scuba unit.[13] This was a revolutionary alternative way to dive, and the start of the transition from the usual heavy underwater diving equipment of the hard hat divers which had been in general use since the 18th century, to self-contained divers, free of being tethered by an air line and rope connection.

In 1933 Italian companies were already producing underwater oxygen rebreathers, but the first scuba diving set is generally recognised inside the USA as being invented in 1939 by Christian Lambertsen, who dubbed it the Lambertsen Amphibious Respirator Unit (LARU).[14] and patented it in 1940.[15] He later renamed it the Self Contained Underwater Breathing Apparatus, which, contracted to SCUBA, eventually became the generic term for both open circuit and rebreather autonomous underwater breathing equipment.

Lambertson demonstrated it to the Office of Strategic Services (OSS) (after already being rejected by the U.S. Navy) in a pool at a hotel in Washington D.C.[16] OSS not only bought into the concept, they hired Dr. Lambertsen to lead the program and build-up the dive element of their maritime unit.[16] The OSS was the predecessor of the Central Intelligence Agency and the maritime element still exists inside their Special Activities Division.[17]

John Spence, an enlisted member of the U.S. Navy, was the first man selected to join the OSS group.[18] In an interview with historian Erick Simmel, Spence claimed that the name "frogman" was coined while he was training in a green waterproof suit, "Someone saw me surfacing one day and yelled out, 'Hey, frogman!' The name stuck for all of us."[18]

The frogman in popular culture

Derivative word usages

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 below. Examples are:

Errors and misconceptions in public media

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.

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.

Mistakes in fiction

Open circuit scuba

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 frogman's position.

Many aqualungs have been anachronistically depicted in comics in stories set during World War II, when in reality, at that time period, aqualungs were unknown outside Jacques-Yves Cousteau and his close associates in Toulon in south France. Some aqualungs were smuggled out of occupied France during the war (these may have been Commeinhes aqualungs), but 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-cylinder aqualungs, as shown on the DVD cover. At the time DESCO were making three-cylinder constant flow breathing sets that lacked the demand valve of the aqualung, but they were rarely deployed in the war, and the preferred system in the US armed forces was the rebreather developed by Dr. Christian J. Lambertsen.[19]

After Ian Edward Fraser in 1957 wrote a book, Frogman V.C., about his experiences, whoever designed its dust cover depicted on it a frogman placing a limpet mine on a ship, wearing a breathing set with twin over-the-shoulder corrugated breathing hoses emitting bubbles from behind his neck, presumably drawn after an aqualung.

The film Submarine X-1, made in 1969, loosely based on the real Operation Source, gets British World War II frogman's equipment very wrong and anachronistic. The breathing sets shown were open-circuit and were merely a very fat cylinder across the belly, with a black single-hose second-stage regulator such as was not invented until the 1960s. Also shown were ordinary recreational scuba weight belts and diving half masks with elliptical windows. The frogmen in the real war operation mostly used Sladen suits and an early model of Siebe Gorman rebreather with a backpack weight pouch containing lead balls releasable by pulling a release cord.

Drawing and artwork

Early model aqualung. Note the regulator with two breathing tubes.

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. The image to the right shows the correct layout of an early model aqualung.

Another common mistake when drawing a diver standing with a bulky backpack breathing set is to show him standing vertically, whereas in reality he would lean forwards somewhat, as the weight of a backpack breathing set (20 kg or more with big twin air cylinders) pushes his center of gravity backwards. The also happens with a film actor wearing lightweight mockup air cylinders (in somewhat the same manner as an actor carrying an empty suitcase or wearing an empty camping backpack).

Nations with military diving groups

See List of military diving units.

See also

Further reading

References

  1. ↑ US Navy (2006). "19". US Navy Diving Manual, 6th revision. United States: US Naval Sea Systems Command. p. 13. Retrieved 2008-06-15.
  2. ↑ Chapple, JCB; Eaton, David J. "Development of the Canadian Underwater Mine Apparatus and the CUMA Mine Countermeasures dive system.". Defence R&D Canada Technical Report (Defence R&D Canada) (DCIEM 92–06). Retrieved 2009-03-31., section 1.2.a
  3. ↑ Aristotle, On the Parts of Animals, ii, 16), transl. by W.Ogle, London, 1882, p. 51:
    “Just then as divers are sometimes provided with instruments for respiration, through which they can draw air from above the water, and thus may remain for a long time under the sea, so also have elephants been furnished by nature with their lengthened nostril, and, whenever they have to traverse the water, they lift this up above the surface and breathe through it.“
  4. ↑ Thukydides, History of the Peloponnesian War, edition Ambrosio Firmin Didot, Paris, 1842, book 4, 26, and b. 7, 25. In Greek and Latin.
  5. ↑ Pierros D. Nick, The tactics of the enemies in the sea warfare during the Peloponnesian War. 1st Pan-Corinthian Congress, Corinth, Greece, 2008. In Greek. N. Pierros is a Civil Engineer and author of historical essays.
  6. ↑ The original Pirelli patented rubber 1930's diving suit
  7. ↑ Manuale Federale di Immersione - author Duilio Marcante
  8. ↑ Short history of A.R.O. from HDS Italy part 2 Pdf
  9. ↑ Short History of A.R.O. from HDS Italy part 1 Pdf
  10. ↑ History of the rebreathers
  11. ↑ Pirelli ARO WW II
  12. ↑ History of A.A.R.S. Apparecchio Autonomo Respirazione Subacquea
  13. ↑ Teseo Tesei e gli assaltatori della Regia Marina author Gianni Bianchi
  14. ↑ Shapiro, T Rees (18 February 2011). "Christian J. Lambertsen, OSS officer who created early scuba device, dies at 93". Washington Post. Retrieved 16 May 2011.
  15. ↑ Lambertsen's patent in Google Patents
  16. 1 2 Shapiro, T. Rees (2011-02-19). "Christian J. Lambertsen, OSS officer who created early scuba device, dies at 93". The Washington Post.
  17. ↑ http://cia.americanspecialops.com/
  18. 1 2 Perry, Tony (2013-11-03). "John Spence dies at 95; Navy diver and pioneering WWII 'frogman'". Los Angeles Times. Retrieved 2013-11-27.
  19. ↑ Vann RD (2004). "Lambertsen and O2: beginnings of operational physiology". Undersea and Hyperbaric Medicine 31 (1): 21–31. PMID 15233157. Retrieved 2009-03-25.

External links

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