11

Helicopter Carriers, Amphibious Forces and other Projects

SINCE THE SECOND WORLD WAR there have been a number of ships built (and many more designed) for ‘auxiliary’, but very important, roles. The main types are replenishment ships to support a task force, and amphibious warfare vessels to land a military force and support it when ashore. Many of these ships are complex and expensive, but they are essential to the success of an operation and hence must have some capacity for self-defence. There is always room for debate on the scale of this self-defence leading into the debate as to whether the ships should be RN or Royal Fleet Auxiliary (RFA) manned, which can have surprising consequences, as will be seen in specific examples later in this chapter.

Cheap Helicopter Carriers

The success of wartime escort carriers and MAC ships encouraged the concept of cheap aircraft carriers or, latterly, helicopter carriers. Early studies were based on the Seamew ASW aircraft, but this proved too small for effective operations against modern submarines. This shows the nub of the problem: an effective aircraft is much bigger – and more expensive – than a wartime Swordfish.

Conduct of operations requires that aircrews be briefed in a capable operations room ‘linked’ to other ships and aircraft. The numerous aircraft, their trained crews and full electronic fit are a major investment that requires protection whatever the cost of the hull, demanding at least a point defence system (including an AIO), signature reduction, subdivision, shock resistance, firefighting, etc; all of these are costly – one has almost defined a CVS.

There are roles in which cheap helicopter carriers are useful, but such roles must be tightly defined to avoid creeping growth and, conversely, to correct any impression that a full aircraft carrier can be obtained on the cheap. The ship with its supplies and aircraft becomes a high-value unit and was seen to require vertically-launched Sea Wolf, full AIO and communications and some signature reduction. Whitehall would not believe the cost estimates. One approach is to combine roles – to carry several helicopters on a replenishment ship. Fort Victoria (see below) can carry four Merlin helicopters in a hangar at the after end, with a sizeable flight deck. While this is a worthwhile solution it has problems, as the vertical motions at the stern of a long ship are severe and airflow over the deck is not good.

About 1980 there was a considerable number of studies into ships which combined the role of replenishment ship and helicopter carrier in different proportions. The simplest variants had a box hangar forward and a big deck with three landing spots aft. This arrangement is only suitable for an aircraft complement of up to about six, above which movement in the hangar becomes too difficult.¹ If more numerous aircraft are needed a conventional carrier style with an island superstructure and flight deck with about five spots and hangar below is required. Two lifts are essential since one may be disabled by accident or damage and lifts to raise a Merlin are not cheap. This configuration would make an alternative deck for V/STOL aircraft to land, refuel and for some limited re-arming. It could not have full maintenance facilities without escalating to the size and cost of a CVS.

There was prolonged discussion about whether these ships should be RN or RFA manned, a discussion that raised some very interesting points. Operation of the ship required far fewer men as an RFA, but since their pay was higher, they had much longer leaves and had bigger and more attractive living quarters, the overall cost seemed little different. The RFA authorities were insistent that it be powered by commercial diesels citing the need for special training as ruling out gas turbines. The RN were equally insistent that it be powered by gas turbines citing the need for special training as ruling out diesels. Once again, there was little difference in the cost – really big diesels do not come cheap. Originally the RN manning would have had a ship CO of Commander rank but when it was decided that the air group needed a Captain it was inevitable that the ship CO would be upgraded. On the standard scale of complement this brought a considerable increase – stewards, a dentist, some instructor officers (meteorologists)!

One major problem applied to both configurations: flight operations made it virtually impossible to have any replenishment rigs on the port side and probably no more than two to starboard. It was not easy in the ‘carrier’ configuration to keep the hangar deck high enough to prevent flooding after damage (and inevitable capsize as in the case of the ferry Herald of Free Enterprise in 1987) and the solution added to the size of the ship.

Two designs for a cheap helicopter carrier with some replenishment capability. The version with a hangar forward (above) is suitable for only up to about six aircraft, beyond which moving within the hangar becomes too difficult. For more aircraft the ‘through deck’ carrier configuration (left) becomes almost inevitable. Neither of these designs was built, but some of the thinking went into Ocean. (D K Brown collection)

The conclusion had to be that the two roles were not compatible. However, much of the thinking was to read across to Ocean (LPH). The design of a helicopter carrier to support amphibious operations proved worthwhile. It would be part of a force containing merchant ships whose signatures would obscure those of the LPH and, since opposed landings are not envisaged, self-protection could be reduced. There is a risk in this, since the LPH is vital to the success of such an operation and its loss would be a disaster.

Argus

During the Falklands War the container ship Contender Bezant (built 1981 near Venice) was requisitioned as a helicopter carrier but reverted after the war (see later section). She arrived in the Falklands area in June 1982 and could carry nine helicopters (including some Chinooks) and four Harriers. Her configuration with twin funnels and two large gantry cranes made aircraft operation difficult.

However, there was still interest in this ship as a replacement for the air training ship Engadine and in March 1984 a contract was placed with Harland & Wolff to purchase and convert her at a price of £63 million; she was renamed Argus.² There were many problems, some unforeseen, such as the presence of asbestos and lead-based paint. Without cargo her stability was excessive, and this was cured in two ingenious ways. The new superstructure, seven decks high, was built of heavy plate (8–10mm), easier to fabricate, weighing 800 tons – the new mast alone weighed 26 tons. In addition, the hatch covers were inverted and the shallow trays so formed were filled with concrete to a total of 1800 tons. Hatch covers in the way of the two 18-ton capacity lifts (weight 55 tons) were removed.³

Argus has a full naval communication fit (Link 11 and 14). She has accommodation for 253 RFA, RN and air group personnel. She can carry out RAS with 3500 tons of fuel plus 1000 m³ of AVCAT. The original machinery has been retained, modified to run on naval-quality dieso. The main and auxiliary engine rooms have been separated by a bulkhead improving subdivision, and the shaft tunnel has been separated from the engine-room. At a full load displacement of 28,081 tons, she was the largest ship in naval service.

She can carry helicopters and transport, but not operate, Harriers; a typical load is twelve Harriers and six Sea Kings. Argus has proved invaluable as headquarters or hospital ship for various intervention forces but there is no such thing as a cheap helicopter carrier. Plans to convert her sister, Contender Argent, were abandoned, to be replaced many years later by Ocean.

Argus served as the mercantile Contender Bezant in the Falklands and was later purchased and given a major conversion to the helicopter carrier configuration seen here. (Mike Lennon)

‘Arapaho’ and Reliant

During the 1970s the USN tried to develop a containerised kit (‘Arapaho’) for fitting to a merchant ship in 3 days and to support four Sea Kings for 15 days. Progress was slow due to lack of funds and the project was recast in 1980. This scheme was followed with interest by the RN and when an urgent requirement came forward in 1982 for a helicopter ship, arrangements were made to lease the US kit. Negotiations were complete early in 1983 but the gear was not yet ready.

However, by May, some eighteen containers and sixty-nine modules forming the hangar and flight deck arrived. Fifty-five more containers had to be fitted out in the UK providing accommodation, water and sewage plant, stores, etc. These were fitted by the end of September and, after two months setting to work, trials began in December 1983. The ship chosen was the Astronomer, which had served as an aircraft transport during the Falklands War, now renamed Reliant.

She served satisfactorily for several years but the concept of a rapid-fit kit built in advance and installed in an emergency was seen to be impractical. Ships varied too much and the kit would have to be designed to fit a particular class, while the ships would need advance preparation. As demonstrated during the Falklands War, quick conversions of container ships as transports can be most valuable but they can never equate to a true helicopter carrier.

Replenishment at Sea

The RN carried out trials in 1902 of replenishing at sea with coal and in 1906 with oil.⁴ Though both trials were said to be successful there was little further development. There is no record of refuelling at sea in the First World War and between the wars there was little interest since the British Empire had numerous fuelling depots world-wide. In the early years of the Second World War it became apparent that few escorts could cross the Atlantic without refuelling and a tanker sailed with each convoy fitted to refuel escorts from astern, though there were experiments in the beam method by 1943.⁵ The full nature of the problem became apparent in the Pacific.⁶ Compared with the USN the RN Fleet Train was slow, unreliable and expensive in manpower. Following the war a major effort was made to catch up. Model tests and cautious trials established safe procedures.

Fort Grange, a replenishment ship for dry stores displacing 22,750 tons, launched in 1976. The ship can operate up to four Sea King helicopters, although normally only one is embarked. (Mike Lennon)

Many trials were carried out, mostly involving Bulawayo (the ex-German Nordmark).⁷ The first task was to develop a self-rendering winch that would pay out as the supports on the two ships moved towards each other due to rolling and other motions in a seaway and then take up the slack as the ships moved the other way. The behaviour of two (or more) ships in close company is complicated, and can be hazardous (as with the sinking of the minesweeper Fittleton by Mermaid in 1976). With the two ships abeam there is an overall force pushing the ships together and a turning moment pushing the bows apart. This is safe but there is a transitional case when the smaller ship is coming up from astern in which the bows are sucked together.

During the Falklands War the mercantile Astronomer was employed as a temporary helicopter carrier, with a hangar made from containers. Later she was purchased, becoming Reliant, and was used for trials with the US ‘Arapaho’ system for conversion to helicopter carrier. In this May 1986 view the ship has a Harrier on deck. (Mike Lennon)

By about 1970 quick and efficient procedures were established and the hardware was available. To ensure that all concerned keep in practice, about 55 per cent of fuel burnt by the RN is taken on at sea. The normal method of refuelling is the jackstay rig alongside, though astern refuelling is possible if both beam stations are occupied. A jackstay rig can also be used to transfer solid stores up to 4 tons in weight, though increasingly helicopters are used for stores transfer (VERTREP).

Replenishment Ships: AOR Fort Victoria

The concept was originally known, informally, as the ‘one stop ship’, an apt description as it was intended to supply fuel, dry stores and ammunition in a single replenishment operation. There were an exceptionally large number of constraints, many of which were not obvious. It had to be able to come alongside at most naval fuel depots to fill its tanks, and the length of the jetty fixed the maximum length of the AOR. It was to be RFA manned which, by agreement, meant that it had to abide by merchant ship rules as far as possible. Both the seamen’s union and the Department of Transport accepted that there would be exceptions, and though they were helpful each exemption required negotiation and justification. Merchant ship rules forbade accommodation over fuel tanks or ammunition stowage but with a large crew and a ship almost full of fuel and ammunition this was not practicable. With such a cargo firefighting capability had to be available at a moment’s notice so that naval practice of a permanently-filled fire main was needed, which meant expensive bronze piping instead of steel – and so it went on. Boat stowage to tanker standards took up upper deck space that was in great demand.

It was soon clear that this would be a most valuable ship whose loss would jeopardise an operation, so on came vertically-launched Sea Wolf, an operations room, Link communications etc, and up went the cost. The first estimate came as a shock to Staff and ministers, and drew the usual parrot-cry of ‘gold plating’. After a long interval a design competition was held, which ended in much higher prices being quoted. This, too, was disbelieved and a further competition was held, which was won by Harland & Wolff. Eventually, Fort Victoria was completed very much in accord with the Ship Department (Brown/Andrews) sketch design, years late and much over budget.

Fort George, a very capable 32,500-ton replenishment ship with fuel, stores and ammunition capability. Three large helicopters are usually carried, but five can be handled if needed. (Mike Lennon)

Amphibious Forces

In January 1958 the Chiefs of Staff invited the Admiralty to examine the technical problems of replacing the ageing amphibious force and the following month a study group was set up.⁸ The force to be lifted was two assault battalions with supporting arms.⁹The study group reported in October 1958 having considered three groups of design.

Bow loading, beaching LST.

Stern loading, non-beaching LST.

LSD.

USN designs were considered but rejected as bigger and more complex than were needed and hence too expensive.

The draught forward of the beaching LST was governed by the ability of wheeled vehicles to ‘wade’, some 5-6ft depending on type (it was assumed that the Centurion tanks would be Duplex Drive, capable of swimming). This limit affected the draught aft, depending on the beach slope selected. UK planners wanted to be able to land on beaches with a slope of 1/120, which meant a shallow draught, small propellers, and a hull form which was resistful and a poor seaboat. US plans called for a 1/50 slope, which made for a more seaworthy vessel at the expense of severe limits on the number of beaches that could be used.

Two studies were prepared for a beaching LST, one with four Deitics (6000shp) and the other with two G6 gas turbines (10,000shp). Speeds above 17kts were not examined as the cost would be high and top speed would only be usable in calm weather. Each vessel carried half a battalion.

There would be few limitations on the form of non-beaching stern loaders and speeds from 18 to 24kts were examined using a version of the Whitby class Y 100 steam machinery for the fastest version. Such vessels did have a major, unsolved problem. Vehicles would be transferred to an LCM using the stern ramp and it was clear that this operation could only be carried out at sea in very calm weather and, even then, it would be slow, taking 5 hours.

The bigger LSD study was based on the USN LSD-28 (Thomaston) but omitting some of the more expensive items of equipment. It could carry a full battalion. This ship was to develop into the Fearless, discussed later. The dock could accept nine LCM or three LCM and one LCU. The smaller LSD could carry two-thirds of a battalion and six LCM. Model tests in both head and following seas were recommended for the beaching LST and the LSD. (The very wide transom of the LSD posed the risk of broaching in a following sea.)

1958 Landing Ship Tank Designs. In 1958 five LST designs were produced. All could carry a tank and vehicle load of 676 tons. The ‘SL’ series were stern loading non-beaching LSTs; the ‘BL’ series bow loading and beaching LSTs. Design SL/A was powered by Y100 steam turbines producing 20,000shp, which gave a speed of 23kts at deep displacement. SL/B, powered by two gas turbines producing 10,000shp with a speed of 19kts at deep displacement, was identical in appearance to SL/C driven by four Deltic diesels producing 6000shp, with a speed of 16kts at deep displacement. BL/C and BL/D were identical in appearance. BL/C was powered by four Deltic diesels, speed being 14kts at deep displacement. BL/D had two gas turbines giving a speed of 16kts at deep displacement. Note the differences in hull design and bridge design. (Drawings by John Roberts from originals in PRO ADM 1/29139)

The estimated costs are of interest.

	Cost (£ million)
Beaching LST	2.75-3.0 + 6 LCA @ £15,000 each
Stern LST	3.-3.5 + 4 LCA @ £15,000 and
	3 LCM @ £50,000 each
LSD	5.0-8.0

For comparison the following figures were quoted at 1958 prices:

	Cost (£1000)
Repeat LCT 8	600
LCT 910	900
LCM 7	35
LCM 8	60
Repeat LST 3	2500
US LPD	$ 30 million

Assault Ships¹¹ Fearless and Intrepid

The wartime Landing Ships Dock, built in the USA,¹² proved of great value in support of amphibious operations and, following the 1958 studies discussed above, it was decided to design and build two similar vessels. These were loosely based on the uss Raleigh, whose plans were made available, and a constructor, Peter Lover, went to sea in Raleigh as a Constructor Commander.

The sketch design was agreed in 1960.¹³ They were intended to carry troops, tanks and other vehicles and land them using their own minor landing craft and, to a limited extent, helicopters. They were also to act as a Brigade Headquarters Ship. They were to carry four LCA(2) in davits, each transporting 35 troops. The LCM 9 was to carry two Centurion tanks or four 3-ton vehicles and stores up to 100 tons. (In 1960 it was thought that there would be no tanks bigger than Centurion but trucks might grow.) The LCM (later LCU) were carried in a dock at the after end of the ship; hence small size was desirable in the LCM. This made a very difficult design problem, and they were never able to carry the full design load, though they were to prove very valuable in the Falklands War. It was intended that the full number of vehicles and men would be landed in five trips by each craft.

When ballasting down, the well deck would be awash in about 30 minutes when it would take a further 15 minutes to flood the dock using four steam pumps. It was immediately apparent that waves in the dock would be a major problem and numerous model experiments were run at Haslar to reduce the problem. In an emergency, it was thought that the ships could make 16kts with the dock flooded.

They have a large helicopter deck but no hangar. Two landing spots were provided but one was obstructed when the full number of vehicles was stowed. They were intended to operate with Wessex helicopters but it was noted that the wheel loading on the deck for vehicles was greater, allowing a margin for bigger helicopters in future. They had accommodation for 400 troops (700 on short crossings) and could carry 15 tanks, six self-propelled guns and up to 50 vehicles (3-ton). Their armament has always been light: originally four Sea Cat mountings and two 40mm, but Fearless had two Phalanx CIWS in 2001.

A model of the Fearless class LSD under test at Haslar in confused seas. Waves within the dock were an additional problem that required extensive testing to resolve. (D K Brown collection)

Particulars
Displacement, deep (tonnes)	11,540
Dimensions (ft)	523 (oa) × 80×20 (deep)
shp/speed (kts)	22,000/20
Fuel, endurance @	2040, 5000 20kts
	6 months out of dock
Complement	450

The estimated cost in 1960 was £8.5 million.

They were ordered and laid down in 1962 as part of an expansion of amphibious forces, completing in 1965–7. They proved invaluable in the Falklands War and in numerous confrontations elsewhere.

LPH Ocean

The primary role of this ship is to carry, operate and maintain a squadron of twelve Sea King or Merlin helicopters in support of the amphibious force and to accommodate a Royal Marine commando of 500 men (800 overload) with their vehicles. Up to six Lynx helicopters can also be carried; Chinooks can be operated from the flight deck (though not hangared) and Sea Harriers can be transported and flown off lightly-loaded.¹⁴

An invitation to tender for the design and build was issued in February 1992 and a contract was placed with VSEL in May 1993.¹⁵ The hull, main machinery and many non-military equipments were to be built by Kvaener Govan (formerly Fairfield) on the Clyde. She was launched on 11 October 1995, incurring some damage, but after repairs and some further outfitting she sailed under her own power to Barrow in November 1996. She was named Ocean by the Queen at Barrow on 20 February 1998 when military equipment had been installed.

Ocean uses a mixture of naval and merchant ship standards. The hull form is that of Invincible but slightly beamier. Subdivision is to RN standards¹⁶ with no fore and aft access below the hangar deck and there are five fire zones and three NBCD citadels. She is longitudinally framed to Lloyd’s rules except for the lower decks and fore and aft ends generally.¹⁷ The steel is of good commercial standard, ductile at low temperatures. The above-water form is mainly of flat surfaces, both to ease fabrication and to minimise radar reflection.

She has the largest hangar ever fitted in a Royal Navy ship –111.3m×21m and 6.2m minimum headroom. There are two 16.75m × 9.75m lifts and two fire barriers. The flight deck has six helicopter spots with parking space for six Lynx. A runway 130m long is available. The vehicle deck is on 4 deck and is 47.5m × 23.25m with a 4.0m headroom. There is a side ramp and a stern ramp for access. Armament comprises three Phalanx CIWS and four twin 30mm. There is a very capable command and control system based on ADAWS 200. Four LCVPs Mark V are carried in davits. Designed and built by Vosper Thornycroft, these can carry 35 Marines and their equipment at 15kts.¹⁸ There is also a Pacific 22 RIB as rescue boat.

1958 Landing Ship Dock. Studies DLVA (top) and DL/B were eventually to lead to Fearless and Intrepid. Both were powered by two Y100 steam turbines producing 20,000shp. Deep displacement speeds were 20kts (DL/A) and 22kts (DL/B). Deep displacements were 11,500 tons (DL/A) and 8000 tons (DL/B). (Drawing by John Roberts from originals in PRO ADM 1/29139)

There are two separated engine-rooms each with a 6750kW Pielstick reversing engine driving through a reduction gearbox.

Sir Lancelot Class LSL

These ships were designed in the 1950s under the direction of the Department of Transport as agents for the War Office and, on completion, they were operated by commercial companies under charter. They had a helicopter deck and could carry 16 main battle tanks, 34 other vehicles and 534 troops. They were built to commercial standards and were not intended for use in opposed landings. They were, however, intended to land troops and vehicles (with Mexiflotes) on suitable beaches in the event that ports were destroyed. Since they were regarded as merchant ships, the rules said that if they grounded they had to be docked for inspection and hence beaching was only practised once, just before a planned docking. They were taken over by the RFA in 1980.

The Big Landing Ship Logistic

By 1980 it was clear that the ‘Sir’ class would need a major update or replacement. A meeting was held in an attempt to clarify requirements. The Army merely wanted a Ro-Ro ship with decks and ramps strong enough to take reinforcements of main battle tanks¹⁹ across the North Sea in a time of rising tension, but the Royal Marines and Navy had a much more elaborate requirement – to loiter off northern Norway for several weeks and then land marines and heavy vehicles.

It was envisaged that the ship should be RFA manned with the usual condition that merchant ship rules should be followed as far as possible. The large number of troops made them into ‘passenger ships’ requiring lifeboats in addition to the landing craft. This translated into a very large vessel, 650ft long and 11,500 tons. The project went no further.²⁰

Sir Galahad

Following the loss of the first Sir Galahad in the Falklands war a replacement was designed and built by Swan Hunter. She is a most versatile ship, carrying fifteen Challenger tanks and other vehicles, together with Mexiflotes and 400–500 troops. Alternatively, she can operate up to six Merlin helicopters, stowed in the tank deck with two large lifts to the upper deck with two spots. During the 1991 Gulf War she served as an MCMV depot ship for five ‘Hunt’ class and three USN minehunters using the containerised Forward Support Unit.²¹ She was able to embark the containers in 20 hours using her own crane and could have disembarked them more quickly had the amphibious landing gone ahead.

Ocean at Marchwood in January 1999. Her hull form is closely based on Invincible. (Mike Lennon)

The LSL Sir Galahad acting as a support ship for five ‘Hunts’, Hecate, and three USN MCMVs in the Gulf in 1991.

(D K Brown collection)

LPD²² Albion and Bulwark

The two new LPD are direct replacements for the aged Fearless and Intrepid. Indeed, the new design team has paid several tributes to their predecessors, including that greatest homage: copying. In particular, the difficult dock design was very closely based on the earlier ships.

In the early 1980s there was a general review of the RN amphibious force, as a result of which it was decided in 1985 to go ahead with two new LPD. Three one-year design studies were funded but failed to produce a satisfactory response. Downs and Ellis²³give the reasons as: firstly, the Ministry was unable to make an input into competitive studies; secondly, splitting design resources between three contenders working on a short timescale meant insufficient depth of study.²⁴ A new study was initiated in 1990 with a single contractor who was forbidden to take part in the design and build stage.²⁵ This ended with a cost estimate some 30 per cent over the planned budget. Yet another study was set up and in 1994 tenders were invited for the detailed design and build. VSEL was the only tenderer and their quoted price was much in excess of budget. After lengthy discussion of cost-saving measures an acceptable price was agreed.²⁶

The payload was almost exactly the same as the earlier ships – 305 troops (405 overload), 31 ‘high’ vehicles or tanks, 36 light vehicles and 30 tons of cargo. The dock could take four LCU Mark 10²⁷ (one USN LCAC hovercraft could be accommodated) and four LCP Mark 5 are carried in davits. There is a side ramp on the starboard side in addition to the stern ramp, and internal ramps connect the vehicle deck to both the dock and the helicopter deck. The flight deck has two spots for Merlin or Sea King and a third stowed, or could accept one Chinook. There is no hangar but some helicopter support facilities are available. Particular attention has been paid to access for fully-equipped troops to assembly areas and on to the deck or dock. Overhead rails are installed to move munitions and heavy stores.

The development of the hull form proved difficult, as most of the weight was forward and the after end was empty. Numerous model tests and computational fluid dynamics eventually reduced the power by no less than 34 per cent compared with the original design. Subdivision is to SOLAS 1990 (roughly two compartment flooding) but firefighting is to RN standards. Watertight wing compartments alongside the vehicle deck aid survivability.²⁸

The hull structure is generally to Lloyd’s rules for fast cargo ships but with higher standards of watertight subdivision and scantlings increased to those suitable for a draught some 2m greater than the actual design draught, for increased strength. External plates are of steel that is tough at low temperatures. Some changes were made to increase resistance to shock from explosions. Fatigue life was set at 10⁸ wave encounters (30 years).

The LPD Bulwark after launching at Barrow. (BAE Systems)

Diesel-electric propulsion was chosen in the light of the wide speed range and manoeuvrability needed. This system requires an engine room complement of about 60, one third of that of Fearless. A bow thruster is fitted. Overall complement is 325, compared with 550 in Fearless.

A very elaborate control and communication system is supplied, since the army commander will be based on the ship during the early phases of an operation as well as the naval task force commander.

Particulars
Displacement, deep (tonnes)	18,500 (c21,500 docked down)
Dimensions (m)	176×28.9×6.1
Power and Speed	Two×6MW;18kts
Armament	Two Goalkeeper CIWS, two 20mm
Radar	Type 996, two Type 1007

Albion is running trials in early 2003.

Landing Ship Dock (Auxiliary) (formerly Alternative Landing Ship Logistic (ALSL))

The Strategic Defence Review of July 1998 envisaged a considerable increase in the RN’s amphibious capability. At much the same time Sir Bedivere showed that the SLEP of these aged LSLs was not cost effective. A review of requirements led to the ALSL, which could transport troops, their vehicles and other equipment and deliver them in an assault role. They would also be able to provide logistic support to troops already ashore, take part in humanitarian operations and work as troopships.²⁹

A contract was placed in December 2000 with Swan Hunter to design and build two ALSL and two more were ordered from BAE Govan in November 2001.³⁰ The new ships will be much bigger than the ‘Sirs’ which they replace, with a deep displacement of 16,000 tons and a length of 176m. They will have diesel-electric propulsion driving a pair of azimuthing thrusters giving a speed of 18kts, similar to that of the rest of the amphibious force. There will also be a bow thruster. Stability will be to warship standards which a study has revealed, unsurprisingly, also satisfies SOLAS 90. The steel is chosen to permit limited operation in ice. They will be fitted ‘for but not with’ light AA guns. The superstructure will be forward without a hangar but with a large flight deck behind – probably one spot for helicopters up to Chinooks or Ospreys in size and a parking space. There will be a dock for one LCU or two LCVP. They will normally carry 350 troops (twice that in overload), and have 2½ times the vehicle capacity of their predecessors. There is a stern ramp and and side ramp well forward. These ships will not beach but disembark their cargo using Mexiflotes which they themselves carry. A particular feature of these ships, developed from Ocean and Albion, is wide troop gangways from berth to assembly area to deck or dock.

Challenger, a seabed operations vessel designed to identify and recover military artefacts from deep water. She fell victim to defence cuts before she could demonstrate her value. (Mike Lennon)

The first ship, Largs Bay, was launched in February 2003 and is due to enter service in July 2004. The first Govan ship will be launched in October 2003. The cost is £95 million each.

The Seabed Operations Vessel Challenger

This ship had a number of difficult roles, all posing problems of ship and equipment design. She was required to search the seabed using hull-mounted sonar in shallow water and a towed, unmanned submersible in deeper water. She was to inspect items found on the seabed, and carry out work using a pressurised diving bell or a submersible with diver lockout facilities, and recover objects. The ‘objects’ could include RN or NATO ordnance lost in exercises, or Soviet devices lost or deliberately placed.

The number of options considered was very large, including two ships, conversions, multi-hull, etc but after consideration a monohull was chosen. She was positioned using two Voith-Schneider units aft and three bow thrusters forward, computer controlled. Her position was determined from satellite systems. A diving bell was operated through a moonpool amidships and an unmanned submersible over the stern. She was designed to RN damaged stability standards to reduce the chance of her sinking. A particular problem would arise if she sank while a diver was in the decompression chamber. A pressure tight tube was arranged to take any such cases to a hyperbaric lifeboat. A RINA paper³¹ discusses the problems which were overcome in much more detail than is possible here. All these features were expensive and she cost as much as a frigate.

Particulars
Displacement (tonnes)	6500 standard
Dimensions (m)	127×18×10.85 (Depth)
Machinery	Five Ruston 16RKCZ driving 3.3kV generators, two 6RKCZ harbour diesels.
Crew	18632

She was completed in 1984 but soon fell victim to defence cuts and was sold. When last heard of (2001), she was mining the seabed for diamonds off Africa.

Icebreakers

In the mid-1950s it was decided to increase the RN presence in the Falklands Islands dependencies. It was hoped to build an icebreaker and the USN generously made the drawings of the ‘Wind’ class available. British engines were selected which made the ship much longer. The cost rose and the project was abandoned, the former netlayer Protector being chosen instead with a minimum of changes. A few years later another design study was progressed in more detail but it, too, foundered on cost. She would have been called Terra Nova; her substitute was Endurance of Falklands fame.

Several attempts were made to design and build an icebreaker to replace the ex-netlayer Protector for Antarctic work but all failed on cost grounds. This is Design Study I for a vessel to be called Terra Nova. This impressive icebreaker/oceanographic survey ship made use of Canadian, American and Scandinavian experience in the design. Deep displacement was approximately 7000 tons with dimensions 278ft × 64ft. Machinery suggested was four Ruston AO engines developing 15,000bhp; ASR1 diesels were also considered. It was cancelled as an economy measure in 1967, her replacement being the purchased Polar Ship Endurance (ex-Anita Dan). (Drawing by John Roberts from original in PRO DEFE 24/90)

¹ See Chapter 4 where similar conclusions were reached in early studies leading to Invincible.

² Anon, ‘RFA Argus, a new air training ship for the RN’, Warship Technology (May 1987).

³ It is said that one has been fitted with an outboard motor and is in use as a cattle ferry on Belfast Loch.

⁴ H W J Chislett, ‘Replenishment at Sea’, Trans RINA (1972), p321.

Respectively, the collier Muriel with Trafalgar, tanker Petroleum with Victorious.

⁵ The ship was Wanderer. See R Whinney, The U Boat Peril (London 1986).

⁶ Vice-Admiral D B Fisher, ‘The Fleet Train in the Pacific War’, Trans INA (1953), p212. This paper was originally issued in 1948 and withdrawn at official request!

Published 1953 without discussion.

⁷ G Jones, Under Three Flags (London 1973).

⁸ ADM 1/29139, October 1958, originally Top Secret (PRO).

⁹ Each battalion comprised 1050 men, 16 tanks (Centurion), 8 self-propelled guns and 60 ‘3-ton equivalents’.

¹⁰ No records have been found of this craft.

¹¹ For a time, the category ‘Assault Ship’ was not thought ‘politically correct’ and they had a range of titles.

¹² Based on a design study by Sir Rowland Baker.

¹³ ADM 167/157 (PRO).

¹⁴ Anon, ‘HMS Ocean – A new helicopter carrier’, Warship Technology, RINA (March 1998).

¹⁵ The losing tender by Swan Hunter was said to be £71 million higher; as a result of this failure the firm went into receivership.

¹⁶ Three compartment flooding.

¹⁷ The big side openings for her landing craft required special design and approval.

¹⁸ The davits can also handle the Dutch LCA Mk 2.

¹⁹ The Army representative said he would like swivelling ramps if they did not cost too much. To my surprise, the ramp manufacturer said that factor of safety on their standard ramp was such that they could accept tanks with very minor changes.

²⁰ Before the second meeting I had a design study with a large scale drawing of the 650ft ship of 11,500 tons which I unrolled towards the end of the meeting. The dialogue was what I had predicted:

Royal Marine colonel: ‘That’s not what we want.’

Brown: ‘But it is what you asked for.’

The army colonel dryly remarked that the fjord where it was proposed to disembark was not 650ft wide – you will have problems!

The meeting adjourned.

²¹ Her Master was most enthusiastic over his ship’s capability but still outlined his ideas for an even better Mark II.

²² LPD is supposed to stand for ‘Landing Platform Dock’, a nonsensical title. In the USN equivalent, P stands for Personnel, a rational interpretation.

²³ This section is based (with permission) on a symposium paper by D S Downs and M J Ellis, ‘The Royal Navy’s New Building Assault ships Albion and Bulwark’, given at RINA Warship ’97; and also the article ‘HMS Albion’ in Warship Technology (May 2001).

²⁴ The author would strongly endorse these views.

²⁵ A very strange approach excluding design teams with experience.

²⁶ It is interesting that one cost saving measure was to increase the size of the ship, making outfit easier. Often advocated, this seems to be the first time it was tried in the UK.

²⁷ The LCU Mark 10 is a drive-through craft with a ramp at each end, speeding dock operation. It can carry a Challenger II tank.

²⁸ Good. Baker got this right in the Second World War, unlike modern Ro-Ro ships.

²⁹ UK details ALSL design. Warship Technology, RINA July 2000.

³⁰ Replacing Sir Geraint and Sir Percivale. They will be named Lyme Bay and Largs Bay. The second pair will be named Mounts Bay and Cardigan Bay. The design is based on the Dutch Rotterdam.

³¹ P J R Symons and J A Sadden, ‘The Design of the Seabed Operations Vessel’, Trans RINA (1982), p41.

³² There was the usual debate as to whether they should be RN or RFA. A naval crew was selected on the basis of security.