A forklift is a powered industrial truck used to lift and move materials over short distances. The forklift was developed in the early 20th century by various companies, including Clark, which made transmissions, Yale & Towne Manufacturing, which made hoists. Since World War II, the use and development of the forklift truck have expanded worldwide. Forklifts have become an indispensable piece of equipment in warehousing. In 2013, the top 20 manufacturers worldwide posted sales of $30.4 billion, with 944,405 machines sold. The middle nineteenth century through the early 20th century saw the developments that led to today's modern forklifts; the forerunners of the modern forklift were manually powered hoists. In 1906, the Pennsylvania Railroad introduced battery powered platform trucks for moving luggage at their Altoona, Pennsylvania train station. World War I saw the development of different types of material handling equipment in the United Kingdom by Ransomes, Sims & Jefferies of Ipswich; this was in part due to the labor shortages caused by the war.
In 1917, Clark in the United States began developing and using powered tractor and powered lift tractors in their factories. In 1919, the Towmotor Company, Yale & Towne Manufacturing in 1920, entered the lift truck market in the United States. Continuing development and expanded use of the forklift continued through the 1930s; the introduction of hydraulic power and the development of the first electric power forklifts, along with the use of standardized pallets in the late 1930s, helped to increase the popularity of forklift trucks. The start of World War II, like World War I before, spurred the use of forklift trucks in the war effort. Following the war, more efficient methods for storing products in warehouses were being implemented. Warehouses needed more maneuverable forklift trucks that could reach greater heights and new forklift models were made that filled this need. For example, in 1954, a British company named Lansing Bagnall, now part of KION Group, developed what was claimed to be the first narrow aisle electric reach truck.
The development changed the design of warehouses leading to narrower aisles and higher load stacking that increased storage capability. During the 1950s and 1960s, operator safety became a concern due to the increasing lifting heights and capacities. Safety features such as load backrests and operator cages, called overhead guards, began to be added to forklifts produced in this era. In the late 1980s, ergonomic design began to be incorporated in new forklift designs to improve operator comfort, reduce injuries and increase productivity. During the 1990s, exhaust emissions from forklift operations began to be addressed which led to emission standards being implemented for forklift manufacturers in various countries; the introduction of AC power forklifts, along with fuel cell technology, are refinements in continuing forklift development. Forklifts are rated for loads at a specified maximum weight and a specified forward center of gravity; this information is located on a nameplate provided by the manufacturer, loads must not exceed these specifications.
In many jurisdictions, it is illegal to alter or remove the nameplate without the permission of the forklift manufacturer. An important aspect of forklift operation is. While this increases maneuverability in tight cornering situations, it differs from a driver’s traditional experience with other wheeled vehicles. While steering, as there is no caster action, it is unnecessary to apply steering force to maintain a constant rate of turn. Another critical characteristic of the forklift is its instability; the forklift and load must be considered a unit with a continually varying center of gravity with every movement of the load. A forklift must never negotiate a turn at speed with a raised load, where centrifugal and gravitational forces may combine to cause a disastrous tip-over accident; the forklift is designed with a load limit for the forks, decreased with fork elevation and undercutting of the load. A loading plate for loading reference is located on the forklift. A forklift should not be used as a personnel lift without the fitting of specific safety equipment, such as a "cherry picker" or "cage".
Forklifts are a critical element of warehouses and distribution centers. It's imperative that these structures be designed to accommodate their safe movement. In the case of Drive-In/Drive-Thru Racking, a forklift needs to travel inside a storage bay, multiple pallet positions deep to place or retrieve a pallet. Forklift drivers are guided into the bay through guide rails on the floor and the pallet is placed on cantilevered arms or rails; these maneuvers require well-trained operators. Since every pallet requires the truck to enter the storage structure, damage is more common than with other types of storage. In designing a drive-in system, dimensions of the fork truck, including overall width and mast width, must be considered. Forklift hydraulics are controlled either with levers directly manipulating the hydraulic valves or by electrically controlled actuators, using smaller "finger" levers for control; the latter allows forklift designers more freedom in ergonomic design. Forklift trucks are available in many variations and load capacities.
In a typical warehouse setting most forklifts have load capacities between five tons. Larger machines, up to 50 tons lift capacity, are used for lifting heavier loads, including loaded shipping containers. In addition to a control to raise and lower the forks, the operator can
A tugboat is a type of vessel that maneuvers other vessels by pushing or pulling them either by direct contact or by means of a tow line. Tugs move vessels that either are restricted in their ability to maneuver on their own, such as ships in a crowded harbor or a narrow canal, or those that cannot move by themselves, such as barges, disabled ships, log rafts, or oil platforms. Tugboats are powerful for their size and built, some are ocean-going; some tugboats serve as icebreakers or salvage boats. Early tugboats had steam engines. Many tugboats have firefighting monitors, allowing them to assist in firefighting in harbors. Seagoing tugs fall into four basic categories: The standard seagoing tug with model bow that tows its "payload" on a hawser; the "notch tug" which can be secured in a notch at the stern of a specially designed barge making a combination ship. This configuration is dangerous to use with a barge, "in ballast" or in a head- or following sea. Therefore, "notch tugs" are built with a towing winch.
With this configuration, the barge being pushed might approach the size of a small ship, with interaction of the water flow allowing a higher speed with a minimal increase in power required or fuel consumption. The "integral unit", or "integrated tug and barge", comprises specially designed vessels that lock together in such a rigid and strong method as to be certified as such by authorities such as the American Bureau of Shipping, Lloyd's Register of Shipping, Indian Register of Shipping, Det Norske Veritas or several others; these units stay combined under any sea conditions and the tugs have poor sea-keeping designs for navigation without their barges attached. Vessels in this category are considered to be ships rather than tugboats and barges must be staffed accordingly; these vessels must show navigation lights compliant with those required of ships rather than those required of tugboats and vessels under tow. "Articulated tug and barge" units utilize mechanical means to connect to their barges.
The tug is attached by a hinged connection. ATBs utilize Intercon and Bludworth connecting systems. ATBs are staffed as a large tugboat, with between seven and nine crew members; the typical American ATB operating on the east coast customarily displays navigational lights of a towing vessel pushing ahead, as described in the 1972 ColRegs. Compared to seagoing tugboats, harbour tugboats are smaller and their width-to-length ratio is higher, due to the need for a lower draught. In smaller harbours these are also termed lunch bucket boats, because they are only manned when needed and only at a minimum, thus the crew will bring their own lunch with them; the number of tugboats in a harbour varies with the harbour infrastructure and the types of tugboats. Things to take into consideration include ships with/without bow thrusters and forces like wind and waves and types of ship. River tugs are referred to as towboats or pushboats, their hull designs would make open ocean operation dangerous. River tugs do not have any significant hawser or winch.
Their hulls feature a flat front or bow to line up with the rectangular stern of the barge with large pushing knees. Tugboat engines produce 500 to 2,500 kW, but larger boats can have power ratings up to 20,000 kW. Tugboats have an extreme power:tonnage-ratio; the engines are the same as those used in railroad locomotives, but drive the propeller mechanically instead of converting the engine output to power electric motors, as is common for diesel-electric locomotives. For safety, tugboats' engines feature two of each critical part for redundancy. A tugboat is rated by its engine's power output and its overall bollard pull; the largest commercial harbour tugboats in the 2000s–2010s, used for towing container ships or similar, had around 60 to 65 short tons-force of bollard pull, described as 15 short tons-force above "normal" tugboats. Tugboats are maneuverable, various propulsion systems have been developed to increase maneuverability and increase safety; the earliest tugs were fitted with paddle wheels, but these were soon replaced by propeller-driven tugs.
Kort nozzles have been added to increase thrust per kW/hp. This was followed by the nozzle-rudder; the cycloidal propeller was developed prior to World War II and was used in tugs because of its maneuverability. After World War II it was linked to safety due to the development of the Voith Water Tractor, a tugboat configuration which could not be pulled over by its tow. In the late 1950s, the was developed. Although sometimes referred to as the Aquamaster or Schottel system, many brands exist: Steerprop, Wärtsilä, Berg Propulsion, etc; these propulsion systems are used on tugboats designed for tasks such as ship docking and marine construction. Conventional propeller/rudder configurations are more efficient for port-to-port towing; the Kort nozzle is a sturdy cylindrical structure around a special propeller having minimum clearance between the propeller blades and the
HMNZS Canterbury (L421)
HMNZS Canterbury is a multi-role vessel of the Royal New Zealand Navy. She was commissioned in June 2007, is the second ship of the Royal New Zealand Navy to carry the name, she is New Zealand's first purpose-built strategic sealift ship. As early as 1988 the Royal New Zealand Navy had identified the need for some form of sealift in the South Pacific. In 1995, this led to the commissioning of HMNZS Charles Upham; the subsequent failure of successive governments to fund the required refits resulted in Charles Upham being sold in 2001. At the same time the newly elected Labour Government directed the navy to exclude the option of a third frigate from the Maritime Forces Review, while the sea lift requirement was part of a wider capability mix desired; the construction of the MRV was sub contracted-out to Merwede Shipyards in the Netherlands by Tenix Shipyards in Williamstown, with the design based on the commercial RoRo ship Ben my Chree. However, the choice of a commercially based design has been criticised after the ship was delivered, as it placed several limitations on the functionality of the ship in rough seas – rather than the coastal environment for which Ben my Chree was designed.
The keel was laid on 6 September 2005 and the MRV was launched on 11 February 2006. The ship completed initial sea trials in the Netherlands and arrived in Australia in late August 2006 for fit-out with military equipment. Final acceptance was delayed due to alterations to the ship's hospital and late delivery of documentation. There were ongoing concerns and redesign activities regarding her performance in heavy seas, doubts about, thrown up during her initial journey to Australia, in fact before actual construction; the MRV was accepted by the New Zealand Government on 31 May 2007 and commissioned on 12 June 2007 in Port Melbourne, Australia by the Prime Minister of New Zealand, Helen Clark. The ship cost NZ$130 million to construct, she was constructed with an ice-strengthened hull to allow her to operate in the subantarctic waters, where New Zealand claims several islands, where Canterbury is to assist scientific expeditions. The vessel was plagued by problems since delivery, having been involved in a number of incidents and being considered less seaworthy than specified.
It was estimated in 2008 that at least another NZ$20 million would have to be spent to achieve the sought-for operational abilities. After commissioning, the ship sailed to its home port of Lyttelton arriving 28 June 2007. After several days of inaugural events, it departed again on 2 July. Following a courtesy visit to Timaru and after a month-long set of trials and exercises in the Auckland area, where she is operationally based at Devonport Naval Base, she is to head to New Zealand's subantarctic waters carrying DOC conservation officers. In September 2007, Canterbury embarked 250 troops and 50 vehicles, including 20 NZLAV armoured vehicles, to test embarkation and disembarkation procedures. In early 2011, it was announced that the ship would form the core asset of a joint Australia-New Zealand task force for disaster-relief operations. At that time Canterbury was the only vessel available to the navies of the two countries suitable for such tasks as three other capable Australian ships were unavailable due to significant maintenance problems.
Coincidentally, the newly appointed disaster-relief ship was in the port of Lyttelton less than two weeks during the devastating February 2011 Christchurch earthquake. The crew provided meals for 1,000 people left homeless in that town, accommodation for a small number of locals. HMNZS Canterbury was the first ship to take scientific samples from a 7,500–10,000 square mile pumice raft, discovered in the Kermadec Islands. After the earthquake on 14 November 2016, HMNZS Canterbury was deployed to provide relief for Kaikoura, as extensive damage to major roads restricted access; the ship delivered supplies from Port Lyttleton to Kaikoura and evacuated Foreign tourists back to Port Lyttleton. Kaikoura airport has a short runway, unsuitable for medium to large aircraft; as a sealift ship, Canterbury is not intended to enter combat, or conduct opposed landings under fire. The ship's armament consists of a single 25 mm M242 Bushmaster cannon fitted to an MSI DS25 stabilised mount, two.50 calibre machine guns, a number of small arms.
These are intended for self-defence against other smaller craft, for ocean patrol duties during a naval blockade. The ship has cargo space of 1,451 square metres, which can be unloaded via two ramps, either from the starboard side or the stern; the indicative cargo would encompass: 14 Pinzgauer Light Operational Vehicles, 16 NZLAV light armoured vehicles, 7 Unimog trucks, 2 ambulances, 2 flatbed trucks, 7 vehicle trailers, 2 rough terrain forklifts, 4 ATV-type vehicles and up to 33 20 ft TEU containers. The ship is equipped to embark up to eight containers of ammunition and up to two with hazardous materials, has an extensive fire sprinkler system; the ship carries two Landing Craft, Medium. The landing craft have a length of a displacement 55 tonnes to 100 tonnes, they are operated by a crew of three, using two Azimuth thrusters generating 235 kW. The LCMs can be loaded via the stern ramp. To aid stern ramp loading, the MRV is fitted with Flippers to ensure that the LCM are aligned with the MRV.
A ballasting system is fitted to allow for safe operations during loading. Once loaded, the LCM can conduct over-the-beach landings, with the boats intended to be able to access beaches in the Pacific where no po
Armoured warfare, mechanised warfare or tank warfare is the use of armoured fighting vehicles in modern warfare. It is a major component of modern methods of war; the premise of armoured warfare rests on the ability of troops to penetrate conventional defensive lines through use of manoeuvre by armoured units. Much of the application of armoured warfare depends on the use of tanks and related vehicles used by other supporting arms such as infantry fighting vehicles, self-propelled artillery, other combat vehicles, as well as mounted combat engineers and other support units; the doctrine of armoured warfare was developed to break the static nature of World War I trench warfare on the Western Front, return to the 19th century school of thought that advocated manoeuvre and "decisive battle" outcomes in military strategy. Modern armoured warfare began during the First World War with the need to break the tactical and strategic stalemates forced on commanders on the Western Front by the effectiveness of entrenched defensive infantry armed with machine guns—known as trench warfare.
Under these conditions, any sort of advance was very slow and caused massive casualties. The development of the tank was motivated by the need to return manoeuvre to warfare, the only practical way to do so was to provide caterpillar traction to guns allowing them to overcome trenches while at the same time offering them armour protection against small arms fire as they were moving. Tanks were first developed in Britain and France in 1915, as a way of navigating the barbed wire and other obstacles of no-man's land while remaining protected from machine-gun fire. British Mark I tanks first went to action at the Somme, on 15 September 1916, but did not manage to break the deadlock of trench warfare; the first French employment of tanks, on 16 April 1917, using the Schneider CA, was a failure. In the Battle of Cambrai British tanks were more successful, broke a German trenchline system, the Hindenburg Line. Despite the unpromising beginnings, the military and political leadership in both Britain and France during 1917 backed large investments into armoured vehicle production.
This led to a sharp increase in the number of available tanks for 1918. The German Empire to the contrary, produced only a few tanks, late in the war. Twenty German A7V tanks were produced during the entire conflict, compared to over 4,400 French and over 2,500 British tanks of various kinds. Nonetheless, World War I saw the first tank-versus-tank battle, during the Second Battle of Villers-Bretonneux in April 1918, when a group of three German A7V tanks engaged a group of three British Mark IV tanks they accidentally met. After the final German Spring Offensives of 1918, Entente tanks were used in mass at the Battle of Soissons and Battle of Amiens, which ended the stalemate imposed by trench warfare on the Western Front, thus ended the war. Tactically, the deployment of armour during the war was typified by a strong emphasis on direct infantry support; the tank's main tasks were seen as crushing barbed wire and destroying machine-gun nests, facilitating the advance of foot soldiers. Theoretical debate focused on the question whether a "swarm" of light tanks should be used for this or a limited number of potent heavy vehicles.
Though in the Battle of Cambrai a large concentration of British heavy tanks effected a breakthrough, it was not exploited by armour. The manoeuvrability of the tank should at least in theory regain armies the ability to flank enemy lines. In practice, tank warfare during most of World War I was hampered by the technical immaturity of the new weapon system causing mechanical failure, limited numbers, general underutilisation, a low speed and a short range. Strategic use of tanks was slow to develop during and after World War I due to these technical limitations but due to the prestige role traditionally accorded to horse-mounted cavalry. An exception, on paper, was the Plan 1919 of Colonel John Fuller, who envisaged using the expected vast increase in armour production during 1919 to execute deep strategic penetrations by mechanised forces consisting of tanks and infantry carried by lorries, supported by aeroplanes, to paralyse the enemy command structure. Following the First World War, the technical and doctrinal aspects of armoured warfare became more sophisticated and diverged into multiple schools of doctrinal thought.
During the 1920s, only few tanks were produced. There were however, important technical developments. Various British and French commanders who had contributed to the origin of the tank, such as Jean Baptiste Eugène Estienne, B. H. Liddell Hart and J. F. C. Fuller, theorised about a possible future use of independent armoured forces, containing a large concentration of tanks, to execute deep strategic penetrations. Liddell Hart wrote many books about the subject propagating Fuller's theories; such doctrines were faced with the reality that during the 1920s the armoured vehicles, as early road transport in general, were unreliable, could not be used in sustained operations. Mainstream thought on the subject was more conservative and tried to integrate armoured vehicles into the existing infantry and cavalry organisation and tactics. Technical development focussed on the improvement of the suspension system and engine, to create vehicles that were faster, more reliable and had a better range than their WW I predecessors.
To save weight, such designs had thin armour plating and this inspired fitting small-calibre high-velocity guns in turrets, giving tanks a good antitank capacity. Both France and Britain built specialised infantry tanks, more armoured to provide infantry
In warfare, a theater or theatre is an area in which important military events occur or are progressing. A theater can include the entirety of the airspace and sea area, or that may become involved in war operations. In his book On War, Carl von Clausewitz defines the term as one that: "Denotes properly such a portion of the space over which war prevails as has its boundaries protected, thus possesses a kind of independence; this protection may consist of fortresses, or important natural obstacles presented by the country, or in its being separated by a considerable distance from the rest of the space embraced in the war. Such a portion is not a mere piece of the whole. To give an adequate idea of this, we may suppose that on this portion an advance is made, whilst in another quarter a retreat is taking place, or that upon the one an army is acting defensively, whilst an offensive is being carried on upon the other; such a defined idea as this is not capable of universal application. Theater of operations is a sub-area within a theater of war.
The boundary of a TO is defined by the commander, orchestrating or providing support for specific combat operations within the TO. Theater of operations is divided into strategic directions or military regions depending on whether it's a war or peacetime; the United States Armed Forces split into Unified Combatant Commands that are assigned to a particular theater of military operations. A strategic direction is a group of armies known as a task forces or battlegroups. A strategic command or direction in general essence would combine a number of tactical military formations or operational command. In the modern military, a strategic command is better known as a combat command that may be a combination of groups; the Soviet and Russian Armed Forces classify a large geographic subdivision – such as continental geographic territories with their bordering maritime areas, adjacent coasts and airspace – as a theater. The Russian-language term for a military "theater" is театр военных действий, teatr voennykh deistvii, abbreviated ТВД, TVD.
The division of large continental and maritime areas assists in determining the limits within which to develop plans for the operations of strategic military groups of forces, allowing military operations of specific significant "strategic directions" known as "fronts", which were named in accordance with their theater of operations. In peacetime, lacking the urgencies of a strategic direction, fronts were transformed into military regions responsible for an assigned section of operations; the term "theater of operations" was defined in the field manuals as the land and sea areas to be invaded or defended, including areas necessary for administrative activities incident to the military operations. In accordance with the experience of World War I, it was conceived of as a large land mass over which continuous operations would take place and was divided into two chief areas–the combat zone, or the area of active fighting, the communications zone, or area required for administration of the theater.
As the armies advanced, both these zones and the areas into which they were divided would shift forward to new geographic areas of control. Battlespace China Burma India Theater European Theater of Operations European theatre of World War II Locus of control Unified Combatant Command Western Theater of the American Civil War Formations of the Soviet Army
A cargo ship or freighter ship is a merchant ship that carries cargo and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year, handling the bulk of international trade. Cargo ships are specially designed for the task being equipped with cranes and other mechanisms to load and unload, come in all sizes. Today, they are always built by welded steel, with some exceptions have a life expectancy of 25 to 30 years before being scrapped. Cargo ships/freighters can be divided into six groups, according to the type of cargo they carry; these groups are: General cargo vessels Container ships Tankers Dry bulk carriers Multi-purpose vessels Reefer shipsGeneral cargo vessels carry packaged items like chemicals, furniture, motor- and military vehicles, garments, etc. Tankers carry other liquid cargo. Dry bulk carriers carry coal, grain and other similar products in loose form. Multi-purpose vessels, as the name suggests, carry different classes of cargo – e.g. liquid and general cargo – at the same time.
A Reefer ship is designed and used for shipping perishable commodities which require temperature-controlled fruits, fish, dairy products and other foodstuffs. Specialized types of cargo vessels include container ships and bulk carriers. Cargo ships fall into two further categories that reflect the services they offer to industry: liner and tramp services; those on a fixed published schedule and fixed tariff rates are cargo liners. Tramp ships do not have fixed schedules. Users charter them to haul loads; the smaller shipping companies and private individuals operate tramp ships. Cargo liners run on fixed schedules published by the shipping companies; each trip a liner takes is called a voyage. Liners carry general cargo. However, some cargo liners may carry passengers also. A cargo liner that carries 12 or more passengers is called a combination or passenger-run-cargo line; the earliest records of waterborne activity mention the carriage of items for trade. The desire to operate trade routes over longer distances, throughout more seasons of the year, motivated improvements in ship design during the Middle Ages.
Before the middle of the 19th century, the incidence of piracy resulted in most cargo ships being armed, sometimes quite as in the case of the Manila galleons and East Indiamen. They were sometimes escorted by warships. Piracy is still quite common in some waters in the Malacca Straits, a narrow channel between Indonesia and Singapore / Malaysia, cargo ships are still targeted. In 2004, the governments of those three nations agreed to provide better protection for the ships passing through the Straits; the waters off Somalia and Nigeria are prone to piracy, while smaller vessels are in danger along parts of the South American, Southeast Asian coasts and near the Caribbean Sea. The words cargo and freight have become interchangeable in casual usage. Technically, "cargo" refers to the goods carried aboard the ship for hire, while "freight" refers to the compensation the ship or charterer receives for carrying the cargo; the modern ocean shipping business is divided into two classes: Liner business: container vessels, operating as "common carriers", calling a published schedule of ports.
A common carrier refers to a regulated service where any member of the public may book cargo for shipment, according to long-established and internationally agreed rules. Tramp-tanker business: this is private business arranged between the shipper and receiver and facilitated by the vessel owners or operators, who offer their vessels for hire to carry bulk or break bulk to any suitable port in the world, according to a drawn contract, called a charter party. Larger cargo ships are operated by shipping lines: companies that specialize in the handling of cargo in general. Smaller vessels, such as coasters, are owned by their operators. A category designation appears before the vessel's name. A few examples of prefixes for naval ships are "USS", "HMS", "HMCS" and "HTMS", while a few examples for prefixes for merchant ships are "RMS", "MV", "MT" "FV" Fishing Vessel and "SS". "TS", sometimes found in first position before a merchant ship's prefix, denotes that it is a Turbine Steamer. Famous cargo ships include the Liberty ships of World War II based on a British design.
Liberty ship sections were prefabricated in locations across the United States and assembled by shipbuilders in an average of six weeks, with the record being just over four days. These ships allowed the Allies to replace sunken cargo vessels at a rate gr
A troopship is a ship used to carry soldiers, either in peacetime or wartime. Operationally, standard troopships – drafted from commercial shipping fleets – cannot land troops directly on shore loading and unloading at a seaport or onto smaller vessels, either tenders or barges. Attack transports, a variant of ocean-going troopship adapted to transporting invasion forces ashore, carry their own fleet of landing craft. Landing ships bring their troops directly ashore. Ships to transport troops were used in Antiquity. Ancient Rome used the navis lusoria, a small vessel powered by rowers and sail, to move soldiers on the Rhine and Danube; the modern troopship has as long a history as passenger ships do, as most maritime nations enlisted their support in military operations when their normal naval forces were deemed insufficient for the task. In the 19th century, navies chartered civilian ocean liners, from the start of the 20th century painted them gray and added a degree of armament. HMT Olympic rammed and sank a U-boat during one of its wartime crossings.
Individual liners capable of exceptionally high speed transited without escorts. Most major naval powers in the late 19th and early 20th centuries provided their domestic shipping lines with subsidies to build fast ocean liners capable of conversions to auxiliary cruisers during wartime; the British government, for example, aided both Cunard and the White Star Line in constructing the liners RMS Mauretania, RMS Aquitania, RMS Olympic and RMS Britannic. However, when the vulnerability of these ships to return fire was realized during World War I most were used instead as troopships or hospital ships. RMS Queen Mary and RMS Queen Elizabeth were two of the most famous converted liners of World War II; when they were converted, each could carry well over 10,000 troops per trip. Queen Mary holds the all-time record, with 15,740 troops on a single passage in late July 1943, transporting a staggering 765,429 military personnel during the war. Large numbers of troopships were employed during World War II, including 220 "Limited Capacity" Liberty ship conversions, 30 Type C4 ship-based General G. O. Squier-class, a class of 84 Victory ship conversions, a small number of Type-C3-S-A2 ship-based dedicated transports, 15 classes of attack transports, of which some 400 alone were built.
The modified Liberties were capable of transporting up to 450, 550, or 650 troops or prisoners-of-war. Modifications included installation of bunks stacked five deep on the forward tweendeck, additional shower and head facilities, two additional diesel-powered generators, installation of two more Oerlikon 20-mm automatic cannons. 30 Type C4 ship-based the largest carrying over 6,000 passengers. A class of Victory ship-based dedicated troopship was developed late in World War II. A total of 84 such VC2-S-AP2 hull conversions was completed. A class of Type C3 ship – comprising C3-S-A2 and C3-S-A3 hulls – was converted to dedicated troopships, capable of carrying 2,100 troops, was developed. At least 15 classes of Attack Transport, consisting of at least 400 ships specially equipped for landing invasion forces rather than general troop movement; the designation HMT would replace RMS, MV or SS for ships converted to troopship duty with the United Kingdom's Royal Navy. The United States used two designations: WSA for troopships operated by the War Shipping Administration using Merchant Marine crews, USS for vessels accepted into and operated by the United States Navy.
Troopships adapted as attack transports were designated AP. In the era of the Cold War, the United States designed the SS United States so that it could be converted from a liner to a troopship, in case of war. More SS Queen Elizabeth 2 and the SS Canberra were requisitioned by the Royal Navy to carry British soldiers to the Falklands War. By the end of the twentieth century, nearly all long-distance personnel transfer was done by airlift in military transport aircraft. James Dugan, The Great Iron Ship, 1953 ISBN 0-7509-3447-6 Stephen Harding, Great Liners at War, Motorbooks Int'l, Osceola, WI, USA, 1997 ISBN 0-7603-0346-0 Goron Newell, Ocean Liners of the 20th Century, Bonanza Books, USA, 1963 ISBN 0-517-03168-X Media related to Troop ships at Wikimedia Commons British Armed Forces Website: Troopships