- Car Carrying Ships
- Performance And Safety
- Variations Of Roro Vessels
- Roro History
- The Expansion Of Ferry Services
- Roro In World War 2
- Transporting Road Vehicles With Roro
- New Developments
Ships that are specifically designed to transport cargo with wheels like trucks, trailers, cars, and railroad cars are called RoRo ships, short for roll-on roll-off. Objects being transported on these ships must be rolled on and off using their own sets of wheels or on top of a mobile platform. The opposite of these types of ships would be LoLo vessels (lift on, lift off) that rely on cranes for loading or unloading their cargo.
RoRo ships use shore based or built in ramps to board/drop cargo. Ferry slips may also be used. Small ferries which can take your car across a river usually use built-in ramps. However, when talking about RoRo, people usually refer to oceangoing ships. The doors and ramps may be placed at the sides, bow, or stern. A combination of these 3 may also be used.
Barges, ferries, cargo ships, and cruise ferries are all considered RoRo vessels. When a new vehicle needs to be moved with a ship, companies will often utilize a PCC or pure car carrier.
When shipping cargo overseas, the metric ton is usually used. However, when it comes to RoRo shipments, LIMs or lanes in meters are the standard instead. Companies will multiply the length of the cargo with its width and number of decks. The length is measured in meters while the width is measured in lanes.
The width of a lane is not the same on all vessels, since the industry has several standards. RT43 or RT units are usually used to measure the cargo capacity of PCCs. These units were created with the 1966 Toyota Corona as the base, it being the first car produced en mass that was transported using specialized automobile carriers. The size of the RoRo vessel was determined based on this vehicle. To ship a Toyota Corona that’s 1.5 meters wide, you’ll need around 4 meters of lane space or 1 RT.
MS Color Magic is the largest RoRo ferry. It is used by Color Line starting in the second half of 2007 and has an internal volume of over 75,000 GT. It can move 550 automobiles at a time. It’s approximately 733 ft long and 114 ft wide, was built by Aker Finnyards in Finland, and has a shipping capacity of 1270 LM of cargo.
However, the largest automobile carrying capacity belongs to Ulysses, a RoRo passenger ferry used by Irish Ferries. It travels between Holyhead and Dublin since 2001. Although its internal volume is lower than MS Color Magic’s at 51,000 GT, it can transport 4101 LM of cargo or 1342 cars.
Car carrying ships
In the first part of the 1960s, cargo ships designed specifically for carrying numerous cars were created. For example, Volkswagen AG used them to ship automobiles towards Canada and the United States. Demand for imported vehicles went up in the 1970s, so RoRo ships also grew in number and diversity.
The first ship designed solely for the transport of cars from Japan was the Toyota Maru no. 10 built by the K line in 1970. 3 years later, the largest PCC was created with a carrying capacity of 4200 vehicles.
Modern PCCs and PCTCs (pure car and truck carriers) are built like a box keeping the cargo fully enclosed. Usually, they have a side ramp and a stern ramp to make loading easier as well as extensive systems for controlling fire. They can transport loose statics, Mafi roll trailers, cars, tracked units, heavy machinery, and trucks.
PCTCs’ decks can be lifted and they’re also much heavier so they may sustain heavy and tall cargo. A ship with a carrying capacity of 6500 automobiles over 12 decks may have 3 decks with a carrying capacity of 136 tons maximum. It will be equipped with panels that can be lifted leaving vertical clearance anywhere between 5 ft 7 in and 22 ft. While these lifting decks make it possible for ships to transport higher cargo, their carrying capacity is reduced in exchange.
These ships can reach a travel speed of 19 knots, while their normal eco-speed is 16 knots.
LCTCs or large car and truck carriers were introduced in 2007 with the Faust carrier. They can transport up to 8000 vehicles at a time. The current largest vessels of this type can transport 8500 CEU. In 2008, the first ship to be partially powered with solar energy was Auriga Leader, a car carrier owned by Nippon Yusen Kaisha.
Performance and safety
Because RoRo ferries have open car decks, very big external doors placed near the waterline, and few internal bulkheads, they’re considered very risky by design and are sometimes nicknamed roll on roll over ferries. Free Enterprise’s MS Herald sank in 1987 due to water going through a loading door that wasn’t properly secured. Water sloshing can make a carrier unstable by causing a free surface effect which may lead to it capsizing. In 1968 in New Zealand, the TEV Wahine capsized due to water on its deck. This problem also played a role in the sinking of the MS Estonia.
On the other hand, these ships benefit from high freeboard raises that compensate for the risks. In 2006, the MV Cougar Ace tilted an impressive 80 degrees without sinking thanks to its high sides which did not permit any water to enter. When the cargo of the MV Modern Express shifted in 2016, it listed too. However, the intervention crew managed to secure and haul it safely.
Variations of RoRo Vessels
- The ConRo. Also known as the RoCon, this type of ship is a combination of container and RoRo vessel. Below its deck, automobiles can be stored while the area above is used to transport containers. The G4 class and similar vessels can transport vehicles, heavy equipment, containers, and oversized cargo. They use separate systems of internal ramps to separate automobiles, break-bulk cargo, and Mafi roll trailers.
- The LMSR. Short for large, medium speed roll on/roll off, this acronym is used for certain types of MSC RoRo cargo ships. MSC stands for military sealift command. While some are designed to transport military cargo exclusively, others have been converted for other types of cargo.
- The RoLo. The roll on lift off ship has hybrid decks designed for transporting automobiles as well as decks meant for cargo. These cargo decks are accessed with a crane or with the changing of the tides.
- The ROPAX. This type of vessel can transport both vehicles and passengers. In theory, any ferry with a RoRo deck which can also carry passengers is a ROPAX vessel. However, if the ship can transport 500 passengers or more, it may also be called a cruiseferry.
The first vehicles were transported overseas just like any other type of cargo. After disconnecting the battery and emptying the tank, an automobile would be placed into the hold, where it would be secured and chocked. The method wasn’t good for regular travel, since it was difficult to use and could easily damage your car.
In 1833, a train ferry was built by Monkland and Kirkintillcoch Railway which used the RoRo method to transport cars in Scotland. In 1849, the Leviathan was built, a modern train ferry. In 1842, a new railway was created trying to reach Aberdeen from Edinburgh. Cargo had to pass through the 5 mile wide Firth of Forth, and they lacked the technology to built a bridge across it. People started looking for an alternative, especially for shipping cargo where the process needed to be as efficient as possible.
Thomas Bouch was hired to find a solution. He proposed creating a train ferry along with a RoRo mechanism. They would create custom ferries with railway lines which would permit the stock to drive on/off it easily. At harbors, they placed adjustable ramps. The gantry structure could be moved on the slipway, changing its height, so it could adapt to the tides. Steam engines were used to load the wagons on/off.
There were other engineers with similar ideas. However, this first achievement belongs to Bouch. He was also very attentive to details, such as how the ferry slip should be designed. As a result, one of the Institution of Civil Engineer’s presidents would counteract those who disputed Bouch over the priority of invention by comparing their simple conceptions with his completed and perfected work.
This type of service was then installed between Burntisland and Granton by Thomas Grainger on the Fifth of Forth. In February of 1850, operations began under the name ‘The Floating Railroad’. Initially, the ferry was supposed to run for a short period until a bridge was built. However, said bridge was finished in 1890 due to the failure of the Rail Bridge built by Thomas Bouche.
The expansion of ferry services
In WW1, train ferries were common. In 1918, supplies, artillery, and railway rolling stock were sent to France for the Front.
For this, 2 ferries equipped with 4 sets of railway line had to be made, so more than 50 wagons could be pushed/pulled on/off the train ferry. Besides railway stock, motor vehicles could also be shipped. At around the same time, another train ferry was built starting from the South East Coast. In just the initial month, more than 5000 tons of cargo was moved through the Channel. Almost 261000 tons were shipped by the year’s end.
There were numerous reasons to replace normal shipping methods with train ferries in WW1. Instead of loading/unloading items repeatedly, it was far more efficient to transport tanks and heavy artillery using ferries.
The country saved numerous man hours by loading guns, tanks, and any other heavy objects they may need at the front using railway wagons. These could then be loaded on a ferry and sent from England to France on a direct route to the Front.
1500 workers were needed to ship 1000 tons of materials needed on the front line while a mere 100 workers could accomplish the same task with train ferries. In 1918, railway companies in Great Britain were lacking workers due to numerous citizens fighting in the war. At the same time, the demand for transportation skyrocketed, so companies had to make the process as efficient as possible.
Even after the armistice was signed, materials had to be shipped back from the front. Even more materials were shipped using train ferries in 1919 from Richborough than in the previous year. Thousands of buses, motor cars, and lorries were sent back to England using ferries.
RoRo in World War 2
The first RoRo ships were built during WW2. After Dunkirk was evacuated by the British in 1940, the Allies and the Admiralty realized they required ships that could cross the ocean to send vehicles such as tanks to Europe for amphibious attacks.
It was decided that 3 GRT tankers would be converted since they had a shallow draft. They were equipped with ramps and bow doors making them the first landing ships that would deliver tanks.
The HMS Boxer was the first LST design built for this purpose. However, due to having to reach 18 knots while carrying the crew, 200 men, 27 vehicles, and 13 tanks, it did not possess a shallow draught. Instead, all 3 ships requested in 1941 would use a long ramp for loading/unloading.
In 1941, The British Admiralty sent a delegation to the United States to discuss with the US Bureau of Ships about making ships in the US including Boxers. The Bureau of ships became responsible for designing them. They would then be built in the US, so shipyards in the UK could focus on making ships for its navy. They were initially called Atlantic T.L.C. or tank landing crafts, since they had to be capable of going across the Atlantic Ocean. It was deemed incorrect to call a 300 ft long vessel a craft, so instead it was renamed an LST, a Landing Ship, Tank.
This type used parts of the design Rowland Baker, now a member of the delegation from Great Britain, came up with. One of these was ensuring the sidewalls had enough buoyancy, so even with a flooded tank deck, they would still float.
The LST did not reach the HMH Boxer’s speed being limited to just 10 knots. However, when beaching, it could draw only 3 ft with a similar load.
Congress gave authority to construct the LSTs and auxiliaries, as well as destroyers for escort and a landing craft. It quickly became a high priority project. In order to build a few LSTs, an aircraft carrier’s keel which was laid previously was removed. In June of 1942, the first LST keel was created in Virginia. In October, the first LSTs left their dock. By 1943, 23 ships were scheduled to be built.
Transporting road vehicles with RoRo
When WW1 ended, ferries were used to transport war vehicles between France and Richborough Port. After this development, a simple idea took hold: Since lorries, guns, and tanks could now be driven onto a vessel, shipped across the seas and oceans, and then driven off the ship on most beaches, why not do the same for civilian and commercial vehicles? With the same crafts and good port facilities, it was definitely possible. Eventually, it grew into today’s international RoRo industry.
After WW1 the Atlantic Steam Navigation Company was created by Frank Bustard. His goal was to provide cheap transport across the Atlantic, but he wasn’t successful. Still, in 1943 he saw an LST’s war trials and was convinced of its capabilities during peacetime.
In 1946, he tried to buy 3 LSTs from the Admiralty. Initially, they didn’t want to sell these vessels. However, they eventually reached a consensus and rented them. Renamend, the Empire Celtic, Cedric, and Baltic, these 3 ships were now in use.
In September of 1946, the Empire Baltic began its first voyage to Rotterdam transporting 64 automobiles to the Dutch. In 1948, the LST 3041 was added to the company, now named the Empire Doric. This was thanks to the ASN managing to earn the support of commercial operators for a route leading from Preston to Lame port in Northern Ireland.
The Empire Cedric was the first to sail on this route in May of 1948. Its services were available twice a week. Soon, it became the ASN fleet’s first ship to have a passenger certificate. It could now transport up to 50 passengers. Therefore, the first ship to work as a RoRo ferry with both commercial and passenger use was the Empire Cedric. The first company to offer such services was the ASN.
In 1953, a RoRo service was initiated starting from Dover across the English Channel. The ASN went under the control of the BTC (British Transport Commission) due to the government’s labor nationalization policy. The fleet grew to 7 vessels in 1955 with the additions of the Empire Nordic and the Empire Cymric. In 1955, the service in Hamburg ended, and a new one was opened going from Antwerp to Tilbury and vice versa. 3 of the fleet’s ships were going to operate in Tilbury while the rest would work between Northern Ireland and Preston.
In 1956 due to the Suez Crisis, ASN’s fleet was sent to the Mediterranean. Its RoRo services were re-opened in 1957. The ASN was given responsibility for managing 12 LSTs from the Admiralty since there wasn’t enough time for them to be used in the Suez Crisis.
In 1956, the Searoad of Hyannis became the first RoRo ship built with the specific purpose of moving semi trucks. It had a limited capacity of 3 fully loaded semi trailers, and it would move between Nantucket Island and Hyannis even in winter.
A new kind of automobile carrier was commissioned by the US military in 1957. Using interior ramps and a stern ramp, cars could easily be driven between the dock and the ship, so the speed of loading/unloading improved greatly. The vessel was called the USNS Comet. It prevented gases from accumulating when the cars went on board using a ventilation system, and it could also lock cars in place with a chocking system.
In 1982, the army requisitioned the SS Atlantic Conveyor for the Falkands War. It would be used in case of emergencies to transport helicopters and aircrafts. In case of an attack from an Argentine aircraft, they kept a Harrier armed and fueled, so it could offer air protection at any moment. Unfortunately, Exocet missiles sunk the Atlantic conveyor. It managed to unload the Harriers it carried, but some helicopters and vehicles sunk with it.
When the war ended, the SCADS came up with a modular system which would turn a big RoRo vessel into an aircraft carrier equipped with work spaces, munitions, radar, crew quarters, ski jump, defensive missiles, and radar. After the end of the war, this system would be easy to remove and then store for future conflicts. This concept was tested by the Soviets too with 2 of their civilian use RoRo vessels.