Dive Equipment in Combat Diving Operations

Breathing Unit

The Breathing equipment used by the military can vary depending on the mission. For routine work such as inspecting a ship or engineering applications open circuit aqualung similar to a scuba configuration is likely to be used.

When a mission calls for the utmost secrecy Closed-Circuit Rebreathers (CCRs) are used. Military CCRs are very sophisticated, complex and require in-depth training to be used safely. Whilst in operation exhaled breath is recirculated into the CCR, 'cleaned' and allow no bubbles escape, thus ensuring its stealth capability. The gas blend of choice is normally pure oxygen as this incurs no decompression requirements and nitrogen fatigue. Two or more oxygen sensors are normally installed which monitor oxygen levels to ensure life support.

Helium blends are used but these tend to in a non-combat situations involving deep recovery operations.

A full-face mask is almost always worn for communications with the support unit and to allow orinasal breathing. In the even of an oxygen toxicity attack the diver is saved from drowning by the mask staying in place, as opposed to an ordinary regulator which is usually spat out during an CNS (Central Nervous System) convulsion.

Common rebreathers used by military divers include the IDA71; a russian designed rebreather. It has about 4 hours duration underwater. Although some say the duration can be increased by ramming the void compartment with extra sodasorb and oxygen. This model is also seen on the civilian market as it is quite an old design.

Insulation

Military drysuits differ a little from typical civilian ones. Most outwardly in the dark colour and ability to resist scrapes and bangs. A bailout bottle is found installed on some to be used in emergencies. Some drysuits are specific to what the situation calls for. An example of this being the 'foul water suit' which is entirely vulcanised and resistant to chemical ingress.

Fins

Military fins are tough, quite large and require a strong set of legs to exert their full potential. They are capable of moving a fully equiped military diver though the water quickly and silently.

Weaponry

As expected on missions requiring incursions against a hostile force or where enemy divers are suspected a lethal weapon (s) is carried. The type carried can vary from army to army. Most types are an assault rifle or a sub-machine environmentally sealed for use under-water. Some are converted for use with fletchettes and harpoons ensuring lethality against hostile divers.

The drawbacks of underwater projectives (usually steel rods or darts which are more accurate than cartridge ammunition) is that they are inaccurate and the barrels wear out rapidly quickly once out of the water.

A russian invovation of the dual purpose-underwater-repeating rifle has answered this problem. Known as an ASM-DT it carries dual magazines, dual feed mechanisms but shoots projectiles through the same barrel. At the surface there are vents for allowing the weapon to be fired using conventional bullets without the water inside the barrel causing it to split under the pressure. This weapon is used by Russian spetznaz and outsourced to western powers. The use of weapons such as these has reduced the danger factor from trained underwater animals that can intercept and attack enemy frogmen. For all the power of the ASM it is bulky and cumbersome to use and most underwater divers prefer the SPP-1 pistol despite it's lack of range.

Military DPV

Strong currents and the need for urgency on operations are always a factor for combat diving ops. Though military divers have a high degree of fitness when a current exceeds 2 knots and the objective is at a long distance tiredness soon creeps in. The military DPV allows for effortless travel to and from an objective requiring covert entry. Performance is unrestrictive with speeds in excess of ten knots possible, these are the fastest known DPVs. Many different types and sizes are used that can transport up to four divers at once with equipment. The type pictured shares some similarities with the recreational DPV, both are neutrally buoyant and are usually man-portable. The similarities stop when it comes to speed and battery life though.

Military SDV

The another type of underwater vehicle is the SDV (Swimmer Delivery Vehicle). It is a large manned underwater vehicle which can be launched from submarines or navy vessels for combat diver ops. Larger, faster and a greater range are key factors for the military SDV. Some can even function as a RIB at the surface and a DPV at depth.

Military DPVs/SDVs are currently unavailable to the civilian market for security reasons. An example of this is the British designed and built SubSkimmer vehicle. To this day it's price is too expensive for any scuba club to consider buying. As time passes and new technology becomes available the civilian sector may start to see the older DPVs become available.

Trained Aquatic Animals

Ever since the 1960s their has been a secretive training program involving training sea creatures intelligent and smart enough to follow commands and orders. Mine clearance, early warning detection of threats and even elimination of hostile frogmen are what dolphins and possible sea lions are capable of targetting.

It is claimed that two Russian frogmen attempting to plant limpet mines during the Vietnam War were killed by a hunter-killer dolphin unit. The development and use of underwater weaponry has meant that the last known clash underwater between frogman and dolphin is said to of resulted in the death of two dolphins. The main method of attack for the dolphins is alleged to be head units fitted with compressed carbon dioxide capules injected into an enemy divers body. The resulting mix hitting the bloodstream causes immediate death. A more less-lethal method is for the dolphin/sea lion to force the frogman to the surface by ramming and pushing.

Mine Clearance System

The EMLB (Emergency Mine Lift Bag) is a system designed to allow fully automated lift-bag which allows hazardous ordinance to be lifted to the surface and subsequantly removed from the area for disposal. If required the system then lowers the ordnance back to the seabed at a controlled rate of descent.

In-Water Communications

Commmunications systems which are incorporated into the divers full-face mask allow diver-to-diver communication over long distances and to the main support base.