An Atmospheric Diving Suit
is a small one-man articulated submersible
form which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere. The ADS can be used for very deep dives of up to 2300 feet (700m) for many hours, and eliminates the majority of physiological dangers associated with deep diving; the occupant need not decompress, there is no need for special gas mixtures, and there is no danger of decompression sickness
or nitrogen narcosis
. Divers do not even need to be skilled swimmers.
The ADS has variously been referred to as an armored diving suit, armored diving dress, articulated diving suit, Iron Duke, Iron Mike, and 'deep-sea diving robot'. The term 'atmospheric diving suit' itself did not come into widespread use until the invention of the JIM suit in the early 1970s.
Atmospheric Diving Suits in current use include the Newtsuit/Hardsuit, and the WASP, both of which are self-contained and incorporate propulsion units. The Newtsuit/Hardsuit is constructed from cast aluminum (forged aluminum in version constructed for the US Navy for submarine rescue), while the WASP is of glass reinforced plastic body tube, (GRP) construction. The upper hull is made from cast aluminum. The bottom dome is machined aluminum.
- 1715: John Lethbridge constructs his " diving engine". Essentially a wooden barrel about in length (1.8m) with two holes for the diver's arms sealed with leather cuffs, and a viewport of thick glass. It was reportedly used to dive as deep as 60 feet (18m), and was used to salvage substantial quantities of silver from the wreck of the East Indiaman Vansittart which sank in 1718 off the Cape Verdes.
- 1838: Englishman W. H. Taylor designed the first armored suit with real joints, which were designed as leather pieces with rings in the shape of a spring (also known as accordion joints). The diver's hands and feet were to be covered with leather. Taylor also devised a ballast tank attached to the suit that could be filled with water to attain negative buoyancy. While it was patented, the suit was never actually produced. It is considered that its weight and bulk would have rendered it nearly immobile underwater.
- 1856: Lodner D. Phillips, designs the first wholly enclosed ADS. His design comprised a barrel-shaped upper torso with domed ends and included ball and socket joints in the articulated arms and legs. The arms had joints at shoulder and elbow, and the legs at knee and hip. The suit included a ballast tank, a viewing port, entrance through a manhole cover on top, a hand-cranked propeller, and rudimentary manipulators at the ends of the arms. Air was to be supplied from the surface via hose. There is no indication, however, that Lodner's suit was ever constructed.
- 1882: the Carmagnolle brothers of Marseilles, France, patent the first properly anthropomorphic design of ADS featuring rolling convolute joints consisting of partial sections of concentric spheres formed to create a close fit and kept watertight with a waterproof cloth. The suit had 22 of these joints: four in each leg, six per arm, and two in the body of the suit. The helmet possessed 25 individual glass viewing ports spaced at the average distance of the human eyes.
- 1894: Australian inventors John Buchanan and Alexander Gordon of Melbourne develop an armored suit. The construction was based on a frame of spiral wires covered with waterproof material. The design was improved by Alexander Gordon by attaching the suit to the helmet and other parts and incorporating jointed radius rods in the limbs. This resulted in a flexible suit which could withstand high pressure. The suit was produced by Siebe Gorman and trialed in Scotland in 1898.
- 1914: MacDuffy constructs the first ADS to use ball bearings to provide joint movement. The suit was tested at New York to a depth of 214 feet (65m), but was not very successful.
- 1915: Harry L. Bowdoin of Bayonne, N.J., patents a new type of oil-filled rotary jointed ADS. The joints use a small duct to the interior of the joint to allow equalization of pressure. The suit was designed to have four joints in each arm and leg, and one joint in each thumb, for a total of eighteen. Four viewing ports and a chest-mounted lamp were intended to assist underwater vision. Unfortunately there is no evidence that Bowdoin's suit was ever built, or that it would have worked if it had been.
- 1915: the German firm Neufeldt and Kuhnke build two atmospheric diving suits based on their patented ball and socket joint, using ball bearings to transfer the pressure load, the bearings sealed by rubber skirts. The suit achieved fame during the salvage of gold and silver bullion from the wreck of the SS Egypt, an 8,000 ton Peninsular and Oriental liner that sank in May 1922. The suit was relegated to duties as an observation chamber at the wreck's depth, and was successfully used to direct mechanical grabs which opened up the bullion storage. The German Navy tested the second-generation suit to 530 feet (161m) in 1924, but limb movement was very difficult and the joints were judged not to be fail-safe, in that if they were to fail, there was a possibility that the suit's integrity could be impaired. The German Navy possessed several Neufeldt and Kuhnke suits, called "Panzertaucher" (armored diver) during World War II, which later found their way into Allied hands after the war, and there are unconfirmed reports that the Russian Navy built copies.
- 1917: Benjamin F. Leavitt of Traverse City, Michigan, dives on the SS Pewabic which sank in in Lake Huron in 1865, salvaging 350 tons of copper ore. In 1923 he went on to salvage the wreck of the British schooner Cape Horn which lay in of water off Pichidangui, Chile, salvaging $600,000 worth of copper. Leavitt's suit was of his own design and construction and he had previously dived to in it in Lake Michigan. The suit used manganese bronze to resist corrosion and weighed only complete, which reduced to underwater, and was lined with sheet rubber for insulation. The arms and legs were constructed of flexible copper tubing with ball bearing joints at knee and elbow, while the helmet had four windows of shatterproof glass and was equipped with a telephone. The most innovative aspect of Leavitt's suit was the fact that it was completely self-contained and needed no umbilical, breathing mixture being supplied from a tank mounted on the back of the suit. The breathing apparatus incorporated a scrubber and an oxygen regulator and could last for up to a full hour.
- 1919: Boston mechanic Charles H. Jackson constructs an ADS which in 1920 is used by John Turner to reach a depth of .
- 1922: British engineer Joseph Salim Peress patents the first spherical type joint which uses a fluid to equalize pressure, and in 1932 built an ADS which was referred to as the Tritonia, and is now commonly called "Jim I." It was successfully used on the wreck of the RMS Lusitania at a depth of . Peress's expertise was later harnessed to help develop the JIM suit, named after Peress's chief diver Jim Jarrett. This was the first practical working ADS.
- 1952: Alfred A. Mikalow constructs an ADS employing ball and socket joints, specifically for the purpose of locating and salvaging sunken treasure. The suit was reportedly capable of diving to depths of and was used successfully to dive on the sunken vessel SS City of Rio de Janeiro in of water near Fort Point, San Francisco. Mikalow's suit had various interchangeable instruments which could be mounted on the end of the arms in place of the usual manipulators. It carried seven high pressure cylinders to provide breathing gas and control buoyancy. The ballast compartment covered the gas cylinders. For communication, the suit used hydrophones.
- 1969: the JIM suit, possibly the most well-known ADS, is invented by the English firm DHB Construction. The first suit was completed in November 1971 and underwent trials aboard HMS Reclaim in early 1972. In 1976 the JIM suit set a record for the longest working dive below 490 feet (149m), lasting five hours and 59 minutes at a depth of 905 feet (275m). The first JIM suits were cast of magnesium because of its high strength-to-weight ratio and weighed around 1,100 pounds in air (including the diver), but the magnesium casting was eventually replaced with glass reinforced plastic (GRP) construction. The GRP suit was known as the JAM suit. A lighter more anthropomorphic suit was built of aluminum or GRP, and was known as the SAM suit. The aluminum model was rated to 1,000 feet (300m) and the GRP suit was rated to 2,000 feet (610m). JIM was eventually surpassed by the WASP Suit (Its sister ADS), and the NEWT Suit, as oil platforms gradually removed subsea walk-ways. Such walk-ways were essential to bottom-walking suits, as JIM was never fitted with any kind of propulsion.
- 1987: the Newt Suit, developed by the Canadian engineer Phil Nuytten. The Newt Suit is constructed to function like a 'submarine you can wear', allowing the diver to work at normal atmospheric pressure even at depths of over 300 metres. Made of cast aluminium, it has fully-articulated joints so the diver can move more easily underwater. The life-support system provides 6–8 hours of air, with an emergency back-up supply of an additional 48 hours.
- 1997: the ADS 2000, developed jointly with OceanWorks International Corp. and the US NAVY is an evolution of the Newt Suit to meet US Navy requirements. The ADS2000 provides increased depth capability for the US Navy's Submarine Rescue Program. Manufactured from forged T6061 aluminum alloy it uses an advanced articulating joint design based on the Newt Suit joints. Capable of operating in up to of seawater for a normal mission of up to six hours it has a self contained, automatic life support system. Additionally, the integrated dual thruster system allows the pilot to navigate easily underwater.
- 2006: the ADS 2000, becomes fully operational and certified by the US Navy during full depth diving off southern California. The existing US Navy program has four ADS 2000 Suits and three self erecting Launch and Recovery Systems. The system is designed to fly away to a rescue site on various military and commercial aircraft.
- Harris, Gary L. Ironsuit: The History of the Atmospheric Diving Suit. Best Pub. Co..