The lighter aboard ship ( LASH) system refers to the practice of loading (lighters) aboard a bigger Marine vessel for transport. It was developed in response to a need to transport lighters, a type of (usually but not always) unpowered barge, between separated by open . Lighters are typically towed or pushed around , or and cannot be relocated under their own power. The carrier ships are known variously as LASH carriers, barge carriers, kangaroo ships or lighter transport ships. shipslist
The LASH system was developed as an alternative and supplement to the developing container system. The lighters, which may be characterized as floating cargo containers, served dual purposes: transportation over water, and the establishment of a modular, standardized shape for loading and unloading cargo. The lighters are loaded onto a LASH carrier at the port of embarkation and unloaded from the ship at the port of destination. Each lighter was approximately (L×W×H), with a capacity of and ; the dry (unladen) weight of each steel lighter was .
The system was developed during the 1960s by the American shipbuilding engineer Jerome Goldman. Acadia Forest, commissioned in September 1969, was the first LASH carrier - the ship could take up 75 standardized lighters, with about 376 metric tons of total loading capacity. At the time, it was a novel kind of ship, the first vessel designed primarily to transport other, smaller ships.
In the late 1980s, the Soviet Union built Sevmorput, a nuclear-powered LASH carrier. Sevmorput is one of only four nuclear powered cargo vessels ever built, and is the largest and the only one in an active commercial service, as it mainly operates in the Russian domestic waters along the Northern Sea Route, where it's unencumbered by the ports' unwillingness to accommodate nuclear ships, a problem that made other nuclear cargo vessels impractical.
Studies showed that the costs of addressing these issues, along with the costs of operating the carrier ships and their lighters, were much higher than for the customary Cargo ship ships or the ISO-compliant container ships that were beginning to conquer the transportation market. While barge carriers and lighters are a technologically interesting sea transport system, they are economic only under certain specific conditions of traffic and economy. article in The Hindu Business Line
article in JOC
In the United States, LASH operators were subject to Jones Act tariffs on the value of repairs made to ships engaged in coastwise trade. LASH operators were thus required to pay a tariff on repairs to their cargo-carrying equipment (barges), unlike container ship operators, who could send their intermodal containers aboard for low-cost repairs. To mitigate this competitive disadvantage, Congress exempted LASH vessels from the tariff.Hadley, Lawrence M. "The Fifty Percent Ad Valoren Duty on Foreign Ship Repairs: Scope of Application and Proposals for Elimination." George Washington Journal of International Law and Economics, vol. 24, no. 2, 1990, pp. 415-454. HeinOnline
An important technical problem raised by the invention of the new transport system was the shape of the lighters. Several other designs, differentiated mainly by the shape of the lighters and the loading mechanism, were proposed, but the LASH system found the largest range of applications. In this approach, the lighters were individually lifted onto the carrier ship by a large gantry crane located at the stern of the ship. The crane could move the entire length of the ship and stack the lighters atop each other in the ship's body and on the deck. The cranes had a load-carrying capacity of more than 500 Mp. Loading or unloading a lighter took on average fifteen minutes. LASH ships were constructed in Europe, Japan and the US with almost uniform parameters.
The host vessel is sometimes purpose-built or modified with a door at the waterline, to allow the payloads to be loaded and unloaded without special lifting equipment. An example would be (originally LASH Turkiye), built at Avondale Shipyard for the American shipping line Prudential Grace, and later transferred to the Ready Reserve Fleet. vesselhistory.marad.dot.gov, SS Cape Mendocino
The first ship of a series of three Sea Bee ships was SS Doctor Lykes, followed by SS Almeria Lykes and SS Tillie Lykes all of which were operated by Lykes Brothers Steamship Company. The "Sea Bee" vessels had three decks and could transport 38 lighters (12 on the lower decks and 14 on the upper deck). The dual function of the ship is noteworthy, as it had storage tanks with a capacity of nearly 36000 m³ volume built into its sides and the unusually large double hull, allowing it to be used also as a product tanker. The ships were later purchased by Military Sealift Command.
Finnish state-owned shipbuilding company Valmet built two barge carriers largely based on the Sea Bee system for the Soviet Union in Vuosaari Shipyard in the late 1970s, and . Of these, Yulius Fuchik was featured in a prominent role in the novel Red Storm Rising by Tom Clancy, where it was modified to masquerade as Doctor Lykes.
The BaCo barges were relatively large compared to the LASH barges, having a deadweight of 800 t, whereby the max. draught was very large with 4.15 m. The BaCo beam of 9.5 m corresponded to the standard beam of European inland waterway transport barges, so that also four Europa barges of Type I could be stored instead of the 12 Baco barges. The container capacity was 652 TEU
In total three were built between 1979 and 1984, named Baco Liner 1, Baco-Liner 2 and Baco Liner 3. Owner was the Baco-Liner GmbH Emden, founded by the shipyard, the Rhein-, Maas- und See-Schiffahrtskontor GmbH (RMS) as well as Rhenus-WTAG, Dortmund. Operator was RMS. The BaCo barges were among others built by Cassens-Werft in Emden.
The Baco-Liners were employed in the liner's service between Northern Europe and West Africa and sailed without major incidents. After the sea transport shifted more and more to containers, the ships were scrapped between 2012 and 2013.
Economic impact
Problems and shortcomings
Preservation
Designs
LASH
Technical data
+ LASH Carrier +LASH Lighter
Sea Bee system
Technical data
+Seabee-Carrier +Seabee-Lighter
BACAT system
Technical data
+BACAT-Carrier
! Parameters !! +BACAT-Lighters
! Parameters !! Lighter type 1 !! Lighter type 2
BACO System
Technical data
+ BaCo-Liner +BaCo shipping units
! Parameters !! BaCo !! LASH
Additional reading
External links
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