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The single largest advantage of a RORO vessel is that vehicles can be loaded and discharged to dockside without the aid of cranes, vehicles simple drive down the ramp and on to their destination.

For vehicles, it is a very efficient process.

Man cannot live of RORO link spans alone, the worlds logistic system revolves around the pallet and ISO container and military logistics  is not really very different. Containers provide security and protection, can be handled using a variety of equipment and most importantly, reduce the number of crane movements per weight, quantity or volume of what is in them.

If CONCEPT 1 has carried out surveys, cleared debris and munitions, repaired equipment and aids to navigations, provided security and dredged channels, the final piece of the jigsaw is allowing the facility to load and unload a variety ships of a variety of cargo, most likely vehicles and ISO containers but potentially break bulk as well.

RORO Ship Concepts

RORO ships are designed to carry wheeled cargo; trucks, tractors, excavators, cars and trailers, they have evolved from simple ferries to mixed vehicle and passenger ships, those that mix containers and vehicles and the large Pure Car and Truck Carrier (PCTC)

Modern RORO ships have their origins in railway ferries, the first of which was the Forfarshire used in the Firth of Forth, built in 1881 and it was a similar design used so effectively in WW1

During the early fifties the more familiar concept was developed in Europe and the USA, often using surplus WWII landing ships.

RORO vessels types include;

ROPAX and Ferries, mixed passenger and vehicles, usually on short sea routes and includes a wide variety of designs.

CONRO, combining containers and roll on roll off, an example of which was the Atlantic Conveyor owned by the Atlantic Container Line.

ACL are bringing into service the G4, more details here

Pure Car Carrier and Pure Car Pure Truck Carrier, these are large specialist ships designed to move high volumes in intercontinental routes.

Freight Only; carrying only vehicles and containers these are a common type of vessel and the UK’s Strategic RORO vessels are typical

The medium sized landing ships in common use in areas with less well developed port infrastructure can also be classed as RORO vessels

Also of course, vessels like the UK’s Landing Ship Dock (Auxiliary) and the US Joint High Speed Vessel are also RORO

This is all well and good but the really important aspect to consider is ramps.

The large Pure Car Pure Truck carriers have two ramps, one in the side of the hull and one at the stern but the stern ramp is angled so that when moored in a conventional position they can load and unload from both.

Other designs only have the stern ramp but they are always angled to allow unloading and loading whilst berthed.

Some RORO vessels have two stern ramps.

A more military oriented example of a stern ramp can be found on the US Military Sealift Command’s Large Medium Speed Roll on Roll Off Ships, the images below shows the USNS Gillliland (T-AKR 298)

As can be seen from the two images the stern ramp is slewable for maximum flexibility.

The UK’s Point Class vessels, the RORO 2700 from Flensberger are the broad equivalent of the T-AKR ships

Instead of a slewable stern ramp they have a large stern ramp and smaller side ramp.

The images below shows Hurst Point at Mare Harbour in the Falkland Islands

And this one of a similar vessel ‘med moored’

The stern ramp can be lowered onto a Mexeflote as shown below

I guess no one approach is right or wrong, just different but if the Point Class is unable to dock stern on the small side ramp may well impede the speed of operations and I am not sure if it is rated for heavy loads like main battle tanks.

It is also likely that future operations, either national or multinational will use a range of civilian vessels. Not all these have such flexibility when it comes to offload and loading ramps.

Link Spans

However they are designed, stern ramps, side or bow, in order to interface with the dockside a link span is often used where the harbour is subject to tidal variation.

As can be imagined, they range from simple ramps to complex designs with split level ramps, hydraulic raising machinery and multiple roadways to facilitate rapid loading and unloading.

There are two components to a typical link span, a pontoon or fixed structure and the vehicle roadway.

Supporting the vehicle roadway can either be a floating pontoon that moves up and down with the tide or a permanent (usually concrete) structure that supports a hydraulically raised and lowered ramp. This structure can either be dockside or at some distance from the dockside depending on individual requirements.

The image below shows a typical single lane floating and spudded link span at Calais that was installed in 2007 for 2.6 million Euros by Marad

This image shows a non floating linkspan

A good primer on the different types of linkspan can be found here and TTS have an equally good range of brochures on

• Full mobile linkspan
• Floating linkspan
• Mechanical Support Linkspan
• Integral Tank Linkspan
• Submerged Tank Linkspan

Temporary solutions can be installed using barges and simple roadways as the example below shows

The example I wrote about in the post on Iraq in 2003 also showed how a temporary solution could be used (in Kuwait) but again, it was not speedy.

The MoD had chartered a lot of RORO shipping to get the Army to Kuwait but although the port of Shuaiba was the preferred location the RORO facilities left a lot to be desired. It was not an option to crane the many hundreds of vehicles over the side so the technical people involved with FIPASS were drafted in.

In less than 30 days they had designed, built and installed a floating linkspan that comprised a 28x14m pontoon attached to two smaller pontoons and a 17m link bridge. The whole system was secured using tensioned steel rope and allowed an unused corner of the port to be used for offloading, a quiet success story

What characterises all these solutions is they are not rapidly deployable and therefore not much use for CONCEPT 1.

A large pontoon based solution would no doubt be suitable but it would need towing to site, never a quick solution, and if CONCEPT 1 is to be limited to in service means of transport that means a modular pontoon, as highlighted in the previous post on debris removal and repair and some sort of compact bridging unit.

Any system cannot be load or size compromised because it will need to accommodate Heavy Equipment Transporters, main battle tanks and possibly Chinook helicopters.

Cimtec engineering have an interesting solution that uses a pontoon and what looks very much like a Mabey Compact 200 panel bridge i.e. son of Bailey

A deployable solution would need three components, the floating platform, the link bridge and some means of securing the whole thing.

The floating platform is obvious, modular pontoons from manufacturers including Damen, Hann Ocean, Robishaw Engineering, Combifloat, Modular Pontoon Systems,Intermarine, Innovo, Baars, Poseidon Barge and Ravenstein, the image below

Securing the pontoon is essential for safe operation so it can either be moored to the dockside, most of the modular pontoon suppliers can provide bollard fittings.

An alternative is to use a jackup attachment, again, most of the pontoon manufacturers can provide these.

The jackup spud legs allow the platform to be raised and lowered not only to accommodate the rise and fall of tides but also for vessels with different ramp geometries.

A jackup solution also allows the landing platform, that joins the vehicle roadway and ships ramp, to be secured at some distance from the dockside. Using mooring ropes means in order to provide stability it would need to be directly adjacent to the dockside. This arrangement would provide much greater positioning flexibility and therefore value in a compromised port.

The Combifloat is a good example, read the brochure here, even the compact C5 series has a deck loading of 15 tonnes per metre squared although its maximum deck load is 80 tonnes which puts it beneath the MLC 120 threshold for a HET and main battle tank so the larger C7 would be more applicable.

Finally, from the landing platform to dockside needs a roadway. These could either be in the form of a single piece or modular. Because the lift capacity available to CONCEPT 1 is limited by the Terex AC55 all terrain crane and large single span able to support a large weight is probably too heavy so the modular solution becomes the obvious answer.

The Logistic Support Bridge, a military version of the Mabey Compact 200, is already in service

Although the LSB would seem ideal a new fabrication might be needed to secure and accommodate the rise and fall of the platform.

Cargo Handling

The Point class Strategic RORO vessels are often used for ISO containers in addition to vehicles, sometimes these ISO containers are carried on the same vehicles that will transport them to their destinations but when these vehicles are not available there is an obvious need for some means of transferring the containers from the RORO ship and into the port area where they can either be cross-loaded onto other vehicles, stored, repacked or otherwise handled.

In addition to vehicles and mobile plant, RORO vessels are increasingly used for break bulk and outsize cargo that is difficult to carry on container ships.

For non containerised cargo a flat ‘Mafi trailer’ is used with a gooseneck

For containers, a container trailer

For moving these container and flat trailers a specialised tractor avoids using normal road going trucks

Terberg and Mafi are representative manufacturers, Terberg, incidentally, are the ones that supply the large Schopf RAF aircraft tractors

These specialist solutions represent the most efficient means of loading and unloading trailers from RORO vessel but it would be equally simply to offload them using standard road going tractors and trailers.

They could also be loaded onto DROPS or MAN SV EPLS (and whatever replaces it) trucks.

The majority of ISO containers arrive at port on dedicated shipping, they are taken from the container ship cells by large port cranes onto the quayside for handling by straddle carriers or directly onto other container handling vehicles or trucks. Container handling in large dedicated ports is increasingly automated and ruthless efficient.

In the scenario envisaged by CONCEPT 1 there may be a complete absence of dockside handling equipment so bring your own is the order of the day but it would be impossible to match the container move rates of a dedicated port equipment such as straddle carriers.

The Points also have a fairly sturdy deck crane, capable of lifting 40 tonnes at 25m outreach and their container capacity is also impressive, 668 TEU’s on Mafi trailers. Many general cargo ships have deck cranes that can offload onto a dockside without port infrastructure.

For offloading RORO vessels, either civilian, military or the Strategic RORO ships, it would be reasonable to deploy a small number of tractor units to quickly offload conventional or Mafi style trailers. These would allow a rapid turn ship around and positioning within the port area.

For container vessels offloading containers requires high cost, very large and very much specialised equipment, completely beyond the scope of CONCEPT 1

The Terex AC55 mobile cranes could be used but container weight and reach would have to be limited.

Moving containers around the port area, onto vehicles and potentially, off ships the in service Rough Terrain Container Handler would be ideal

The Kalmar RTCH can also be used for container handling off Mexeflotes or other landing craft/pontoons

For CONCEPT 1, therefore, the best solution is to make use of existing equipment, mobile cranes, reach stackers, DROPS/EPLS and container handlers,  with a small increment of trailers and terminal tractors.

Landing and Access Stages

The modular pontoons featured above tend to be steel construction and ISO container size, for some applications, such as landing stages for small craft or personnel access recent developments in plastic pontoons are seeing widespread adoption, including by the MoD that has installed units in the new RM Tamar amphibious warfare centre of excellence in Plymouth and they were also on show at the recent DSEI show in london.

The UK company Aqua Dock is one supplier, another successful and innovative British company we need to hear more about

Click here for the brochure

CONCEPT 1 would at very little cost include a small quantity

Sources and Further Reading

The design of ship to shore linkspans for ro-ro terminals

Design of Marine Facilities

McGregor Navire Linkspan Equipment

Other Posts in the Series

Ship to Shore Logistics – 01 (Introduction)

Ship to Shore Logistics – 02 (History – 1944 Europe)

Ship to Shore Logistics – 03 (History – 1982 the Falkland Islands)

Ship to Shore Logistics – 04 (History – 2003 Iraq)

Ship to Shore Logistics – 05 (History – 2010 Haiti)

Ship to Shore Logistics – 06 (Case Study Observations)

Ship to Shore Logistics – 07 (Doctrine and Concepts)

Ship to Shore Logistics – 08 (Requirements and Drivers)

Ship to Shore Logistics – 09 (Current Capabilities and Future Plans)

Ship to Shore Logistics – 10 (Allies – the USA)

Ship to Shore Logistics – 11 (Mid Point Review)

Ship to Shore Logistics – 12 (Ports, Beaches or Both)

Ship to Shore Logistics – 13 (Expeditionary Port Access Concepts)

Ship to Shore Logistics – 14 (Expeditionary Port Access – Concept 1 – Survey and Munitions Clearance)

Ship to Shore Logistics – 15 (Expeditionary Port Access – Concept 1 – Repair and Debris Removal)

Ship to Shore Logistics – 16 (Expeditionary Port Access – Concept 1 – Dredging, Aids to Navigation and Mooring)

Ship to Shore Logistics – 17 (Expeditionary Port Access – Concept 1 – RORO Link Span and Cargo Handling)

Ship to Shore Logistics – 18 (Expeditionary Port Access – Concept 1 – Deployment Options)

Ship to Shore Logistics – 19 (Expeditionary Port Access – Concept 2 – Introduction)

Ship to Shore Logistics – 20 (Expeditionary Port Access – Concept 2 – Lighterage and Intra Theatre Lift)

Ship to Shore Logistics – 21 (Expeditionary Port Access – Concept 2 – Piers and Causeways)

Ship to Shore Logistics – 22 (Expeditionary Port Access – Concept 2 – Materials Handling)

Ship to Shore Logistics – 23 (Expeditionary Port Access – Concept 2 – Wave Attenuation)

Ship to Shore Logistics – 24 (Expeditionary Port Access – Concept 2 – Transport and Deployment)

Ship to Shore Logistics – 25 (Expeditionary Port Access – Concept 2 – Organisation and Funding)

Ship to Shore Logistics – 26 (Summary)

 

 

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It seems that the long awaited first flight of Taranis in Australia has already taken place but been kept a under wraps. I would love to know  more about this aircraft and many of the outlandish claims in the media including that it is super sonic with a 2,000 – 4,000 mile range and one of the lowest Radar Cross Sections ever recorded. But the men at the ministry are giving nothing away for once.

 

 

http://www.janes.com/article/28899/taranis-makes-maiden-flight

 

http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_10_25_2013_p0-630512.xml

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Due to the ongoing sequestration and budget battle in Washington the US Army has been forced to delay its Apache new build and rebuild programs to AH 64 E standards. This means the current type as used by the British Army is likely to be supported for longer giving the MOD some vital breathing space to decide what to do about its Apaches.

Currently UK thinking seems to be slanted towards going for a rebuild on the current fleet but reported costs for the US program would put a rebuild on the entire UK Apaches fleet some where north of $600 million which is probably not something the MOD can consider for the next few years at the very least.

However as the rebuild will see the fuselage and main rotor replaced, if it was to go ahead would it be worth the UK looking at a marinised version? The aircraft is said to have performed very well from Ocean but it has some severe maintenance issues when being used in a salt water environment. Could a rebuild offer us the chance to solve some of these issues and produce a truly purple asset.

http://www.janes.com/article/29255/adex-2013-us-sequestration-buys-time-for-uk-apache-decision-makers

 

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