Type Designation: Amphibious Assault Ship, Helicopter (LPH)
Displacement, tons: 21,578 full load
Guns: 2 GAM-B01 single 20mm mountings; 3 Vulcan Phalanx Mk15.
Programmes: Initial invitations to tender were issued in 1987.
Tenders submitted in July 1989 were allowed to lapse and it was not
until 11 May 1993 that a contract was placed with Vickers Shipbuilding
and Engineering Ltd (VSEL). The hull was built on the Clyde by
Kvaerner Govan Ltd and sailed under its own power to Vickers at
Barrow in November 1996 for fitting out and the installation of military
equipment. Estimated cost is £201 million.
HMS Ocean restores to the Royal Navy's a dedicated amphibious aviation support capability lapsed since the sale of HMS Hermes to India in 1986, and for the first time provides the service with a Landing Platform Helicopter (LPH) ship designed from the outset to meet the specific needs of amphibious operations and Commando aviation. HMS Ocean has a 20 year design life, and is currently scheduled to pay-off in 2018.
A sister ship to Ocean was originally planned but abandoned long before any order was placed on cost grounds. It is currently envisaged that while HMS Ocean is in major refit one of the three Invincible Class CVS's will stand as the LPH in the RN's Amphibious Group. However it is unclear what will happen after the Invincible's are replaced by only two of the new CVF aircraft carriers - only one of the new carriers will normally be operational and she is very unlikely to be available for use as a LPH. Other alternatives such as RFA Argus have when forced to operate in a LPH role proved to be very unsatisfactory. It is therefore to be hoped that in the next few years the idea of a sister ship will be resurrected.
Ocean constitutes the first part of a wider equipment programme to revitalise the UK's amphibious shipping capability. This entails the provision of a core force comprising Ocean, the new Landing Platform Dock (LPD) ships HMS Albion and Bulwark (entering service from 2004 to replace HMS Fearless and Intrepid) and five Landing Ship Logistic (LSL) vessels (including four new-build ships to enter service from 2006), from which Commodore Amphibious Task Group will be able to assemble a mobile, flexible and sustainable amphibious force.
Ocean has blazed a new trail in naval procurement by bucking the trend in the hitherto steady upward movement of large warship construction costs. Ordered at a cost of less than £150 million (US$263m), and estimated to have cost around £200 million fully equipped, the ship has been procured at a price little more than that of a modern frigate.
Ocean is the first major RN warship to be largely designed to commercial classification society standards, allowing the cost reduction benefits of mercantile shipbuilding practice to be reaped. Furthermore, the widespread use of commercial standards and equipments pioneered in Ocean is informing the design processes, construction methods and systems technologies for other major naval projects, notably the Future Aircraft Carrier (CVF).
The relatively low speed of the ship has caused comment and concern.
Tenders for a 'whole ship procurement' were invited in October 1988, with three consortia submitting bids received in July 1989. However, the Ministry of Defence's (MoD) budgetary provision of £105 million per ship proved totally unrealistic, forcing the ASS procurement to be shelved.
The end of the Cold War, and the attendant 'Options for Change' defence review completed in 1990, saw the ASS programme resurrected (albeit for just one ship). Approval to re-open the competition for what was now cast as an LPH came in November 1991, the MoD having re-visited the original requirement and identified areas where the procurement specification could be relaxed to meet a budget cap in the region of £170 million.
An invitation to tender was issued in February 1992. Bids were received from Vickers Shipbuilding and Engineering Limited (VSEL) and Swan Hunter Shipbuilders that October, with the intention to place a contract by the end of November 1993. However, as 1992 drew to a close, a budget-driven planning blight within the MoD cast a dark cloud over the future of the programme.
It was thus a fortunate coincidence that in early 1993 the RN was forced to press the air training ship RFA Argus into service as a makeshift LPH during operations off the Former Republic of Yugoslavia. The accommodation and facilities on board proved totally unsuitable for the demands of a large embarked military force, reaffirming the need for a purpose-built asset.
Ministers subsequently reaffirmed the place of the LPH in the equipment programme, and the procurement process was 'reactivated' in March 1993. Given concerns over Swan Hunter's financial position, the MoD decided to accelerate the procurement process in order to ensure competition and give Swan Hunter management an opportunity to secure the future of the yard.
Initial tenders from the two bidders were close in price, but were both assessed to be non-compliant in some significant areas. In addition, Swan Hunter's overhead provision was assessed to be unrealistic. Following a short period of clarification talks, best and final offers were requested on 26 March 1993 against the procurement specification (revised to take account of the clarification process).
When the new bids were submitted on 22 April it was immediately evident that a significant price differential had emerged, with VSEL lowering its price to £139.5 million (in effect opting to support the bid from its reserves); Swan Hunter's offer had increased to over £210 million. The recommendation to the MoD's Equipment Approvals Committee to award the contract to VSEL was endorsed on 30 April. Following the inclusion of certain costed options, a £143.9 million fixed-price contract to build the LPH, given the name HMS Ocean, was awarded to VSEL on 11 May 1993. Two days later Swan Hunter was forced into receivership. (VSEL itself was purchased by GEC in 1995; it now constitutes the Barrow operation of Marconi Marine [part of Marconi Electronic Systems, which itself has been sold by GEC to British Aerospace, now called BAE Systems!])
A contract with KGL was agreed on 31 August 1993. First steel was cut on 20 May 1994, with the ship assembled from eight pre-fabricated hull blocks delivered to the slipway between March and July 1995.
Launching on 11 October 1995 was intended to be a low-key affair without ceremony. Unfortunately, damage to the hull (including a breach in one tank) sustained as the ship went down the slipway meant the event garnered a rather higher profile than intended. Repairs were later completed in the dry dock at the Scotstoun yard of Yarrow Shipbuilders Limited (also part of Marconi Marine).
On completion of fitting out of all non-military elements of the ship, Ocean sailed from KGL's yard on 18 November 1996 for a 10-day period of contractor's sea trials in the Clyde estuary. The ship was signed over to VSEL on 25 November, and berthed alongside in Buccleath Dock at Barrow-in-Furness on 28 November for the installation, outfitting and setting-to-work of those features required to make the vessel fit for military purpose.
Ocean was officially named by HM The Queen at Barrow on 20 February 1998. The ship had originally been planned to leave its fitting-out berth on 25 March to sail to Devonport. However, during basin trials alongside, a steel hawser became entangled around the port shaft and propeller. This delayed Ocean's departure and also necessitated an unprogrammed docking period at the facilities of Fleet Support Limited in Portsmouth.
The LPH eventually sailed on 23 April, arriving in Portsmouth two days later to dock down (celebrations to mark the 25th anniversary of the UK/Netherlands Amphibious Force were hosted on board on 8 May). Following completion of repairs to the shaft bearings, Ocean sailed from Portsmouth on 12 June to conduct an intensive 48-hour programme of contractor's final machinery trials. Arriving in Devonport on 14 June, Ocean was handed over to the RN on 26 June 1998.
Part IV trials, which test all aspects of the ship's operational and functional capabilities, commenced following a seven-week period of maintenance, defect rectification and guarantee tasks. Ocean sailed on 7 September to undertake a first set of First of Class flying trials with the Sea King HC.4, Gazelle AH.1 and Lynx AH.7, returning to Devonport for its commissioned ceremony on 30 September 1998.
Further first of Class flying trials in January 1999 cleared the Chinook HC.2 helicopter for operations from Ocean. The ship passed its Operational Date Material Assessment on 13 March 1999 and then underwent a four-week programme of Basic Operational Sea Training during April with 40 Commando embarked.
Exercise 'Aurora', the culmination of the ship's work-up to full operational readiness, followed in May 1999. Originally intended to take place in training areas on the eastern seaboard of the US, the exercise was condensed in to three weeks and switched to home waters as a "prudent contingency measure" with the intensification of Operation 'Allied Force' in the Balkans. Indeed, while the exercise was in progress it was announced that an amphibious ready group comprising Ocean, the LPD Fearless, three LSLs and an auxiliary oiler replenishment ship had been put on standby to deploy as part of the Kosovo peace implementation force.
'Aurora' marked the most stressing test of the LPH's operational capability, requiring the ship - operating as part of a task group - to deliver two companies of 42 Commando ashore in a simultaneous air and sea assault in landing areas on the north Devon and south Wales coasts. With all work-up objectives achieved, readiness state R2 - putting Ocean at five days notice for sea - was declared on 31 May, a full month ahead of schedule.
In some cases these systems are fully compliant to naval performance requirements; in others, COTS systems have been ruggedised to comply with more stringent naval standards, or have been integrated into an overall system designed to military practice. In those areas where military pedigree is essential, full naval engineering standards have been applied to meet requirements for operational functionality, safety, strength, firefighting and operation in the military environment.
The structure of the LPH is designed to meet the requirements of Lloyds Register of Shipping (although its design does not conform to any conventional classification society ship types, requiring direct calculation procedures to meet Lloyd's requirements). Ocean is very much pioneering for the use of commercial standards and techniques in the RN; lessons learned have been incorporated in a new set of rules developed by Lloyd's Register (in co-operation with the Directorate of Naval Architecture in the Defence Procurement Agency) which will be formally published in January 2000.
Ocean's underwater hull form is a simple waterline beam variation of the Invincible class. To comply with naval engineering standards for intact and damaged stability, the ship is subdivided into 17 watertight compartments along its length. The hangar deck (5 Deck) is designated as the damage control deck and has fore and aft access on either side at this level. Access below 5 Deck is restricted to each watertight compartment.
In all, the LPH comprises over 1,000 separate compartments. Of these, around 100 are currently void spaces, offering considerable potential for additional storage or equipment spaces. Two previously unallocated areas have already been equipped as fitness suites, another as a synthetic small arms range. Ocean is further divided into five fire zones and three NBCD citadels. The forward and aft engine and auxiliary machinery rooms are arranged to allow three-compartment flooding without affecting other like rooms.
Propulsion power comes from two Crossley Pielstick 12-cyclinder PC2.6V medium-speed diesels, each with a continuous rating of 6,750kW. Design speed is 18kt, though a speed of 20.6kt was sustained during full power trials in June 1998. Each engine drives through a 3:1 reduction gearbox via a solid propeller shaft to a five-bladed skewed fixed-pitch propeller. It should be noted that there is no reversing capability in the gearbox; it is the engine that needs to rotate in the opposite direction to generate astern thrust.
Although the propulsion system itself is designed to Lloyds rules, there are additions to meet military duty requirements. Two engine rooms are provided, each housing one main diesel and half of main generating capacity to provide redundancy. Extra damage isolation is fitted, cross connections incorporated and additional shock protection afforded.
Electrical power is provided by four Ruston 12RKCZ main generator sets with Hyundai alternators, each rated at 2MW. An emergency supply can de drawn from an additional 890kW Paxman Vega diesel operating in conjunction with a Stamford alternator. Siemens is responsible for the ship's main electrical power generation and distribution system, as well as carrying out electrical design and installation engineering. The complete installation includes two Type S404 main power and one emergency power switchboards totalling 34 panels (complete with automatic generator and load control), eight Type S404 group starter boards and 24 electrical distribution centres.
Somewhat unusually for a warship, Ocean has two Brown Brothers stabilisers (which are fully retractable when going astern or berthing). A 450kW KaMeWa bow thruster is fitted to assist with confined manoeuvres. The main engines and diesel generators are managed from the Ship Control Centre on 6 Deck using a Radamec machinery control and surveillance system.
As built, Ocean was equipped with four Caird and Rayner reverse Osmosis desalinisation plants, each of which can produce 80 tonnes of potable water per day. Early operating experience has resulted in the installation of a fifth plant.
Designed for the EMF
"Those converted aircraft carriers previously used by the RN as commando carriers were not specifically designed to accommodate, support and facilitate the military force aboard ship," explains Colonel Simon Guyer, Ocean's Amphibious Operations Officer and commanding officer of 9 Assault Squadron Royal Marines. "Ocean is different. She has been built around the marine and his bergen, and is designed to deliver him ashore in the most timely and efficient manner."
The design took the needs of the EMF into consideration from the outset, drawing on user input and operational experience to identify those factors most critical to the Commando group. "There was still the knowledge around from those with experience on board Bulwark and Hermes," said Col Guyer. "A lot of the standard operating procedures we use have been uplifted from those two previous ships and then refined to suit the superior EMF facilities afforded by Ocean.
"The big difference is the tempo," explains Col Guyer. "In the old carriers it took an hour to get marines from their messdecks, issue a lifejacket and get them to the flight deck. The assault routes were tortuous. "The same process takes 20 minutes at assault stations in Ocean. Also, the Sea King HC.4 gives us much greater carrying capacity than the Wessex."
EMF accommodation has been laid out to suit assault requirements. The bulk of the Commando is accommodated forward, with assault routes running direct to the hangar assembly areas. All passageways and stairways on these routes have been suitably sized to enable a fully equipped marine (in full Arctic warfare kit) to pass through unhindered. As well as being double width, the assault routes feature wide, sill-free openings, high hatchway deckheads and an incline of no more than 45¡. From the hangar assembly points, the marines will then move directly to the four LCVP bays (on 4 Deck) or via the aircraft lifts to the flight deck.
The vehicle deck (located aft on 4 Deck) has been designed to offer maximum loading flexibility. A side ramp is incorporated for quayside loading, and a stern ramp is fitted to allow for loading from either a low quayside or mexeflote. The deck itself provides parking space for up to 40 Land Rover variants, 34 trailers and six 105mm light guns. For internal vehicular movement, Ocean is fitted with a fixed ramp to allow access between the vehicle deck and flight deck offload points. There is also access (via a large watertight door) to the aft aircraft lift for transfer to either the hangar or flight deck.
The EMF's stores and armouries are sited adjacent to the hangar. Large deep magazines are located below the waterline, connected by weapons' lifts to the hangar and flight deck.
By adopting a three-abreast layout in the hangar, aircraft can be moved to either of the two lifts (for transfer to the flight deck above) without infringing the maintenance area. The operational requirement for the LPH demands that 12 Sea Kings with troops and/or underslung loads are launched in two waves of six inside 30min while maintaining an armed aviation patrol airborne throughout the period of the assault.
The flight deck area is 170m in length, with six on-line operating spots (clear of the aircraft lifts) and parking space for a further six helicopters. The operating spots are arranged so as to cater for Merlin, Sea King and Lynx helicopter operations. Two AVCAT pump rooms provide aviation fuel in quantity to the six helicopter positions on the flight deck and three further positions within the hangar. Dieso is supplied to the vehicle deck and hangar.
HMS Ocean does not have aircraft permanently assigned to her. Rather she normally embarks a tailored air group (TAG) drawn mostly from the navy operated "commando" helicopter force within the tri-service Joint Helicopter Command. This consists of 845 Naval Air Squadron (NAS) and 846 NAS each operating the medium size Sea King HC.4 (able to carry 16 troops or an underslung load of 4,500 lb); and 847 NAS operating the Lynx AH.7 (equipped with TOW anti-tank missiles) and Gazelle AH.1 light/reconaissance helicopters. However, Army and RAF helicopters, including the heavy lift Chinook, regularly form part of the TAG.
An absence of traditional workshops, coupled with the requirement for amphibious squadrons to embark much of their deployable support equipment and spare in other platforms, has led to the development of a new concept for engineering support of amphibious aviation at sea. This includes the embarkation of containerised Amphibious Support Package (ASP) modules specific to the size and composition of the embarked TAG, with individual ASP modules installed in purpose-built hanger recesses.
Ocean has the ability to land, operate and provide flight-servicing facilities for the larger Chinook helicopter. Up to four of these aircraft can be sited on the flight deck simultaneously. The ship also has the capability to cross-deck US Marine Corps CH-46 Sea Knight helicopters and the new MV-22 Osprey tilt-rotor. The imminent introduction of the WAH-64D Apache attack helicopter into UK service will add another dimension to Ocean's mix of embarked air assets. It is envisaged that a flight of six Apaches could be routinely embarked (in place of the Lynx) from 2003 to provide anti-tank, combat support and reconnaissance capabilities in support of expeditionary forces ashore.
These same aviation facilities can also be used in a number of secondary roles: Ocean can embark, support and deploy an anti-submarine warfare helicopter squadron of up to 12 Merlin or Sea King helicopters (when operating in close conjunction with an Invincible-class carrier). Alternatively, it can be used as a base for maritime counter-terrorist operations, to support afloat flying training or as a ferry for Sea Harrier aircraft.
Sleeping accommodation for the ship's 283 crew is provided principally on 6 Deck. Sited aft of the hangar deck on 5 Deck are a 50-seat wardroom and 40-seat anteroom, a 60-seat senior rates mess and a 174-seat junior rates messroom. A medical complex on 2 Deck offers self-contained medical, surgical and dental facilities.
The casualty reception area immediately outside has direct access to the aircraft lift, enabling the fast transfer of casualties from the flight deck and hangar.
Ocean is the first ship to be fitted with the Alenia Marconi Systems ADAWS Mod 1 (Colour Variant) command system, also known as ENA. Offering functionality similar to that of the ADAWS Mod 1 systems fitted to the Invincible-class CVSGs and Type 42 destroyers, the ENA system retains F2420 mainframe processors and re-uses existing ADAWS software, but introduces colour display technology, a UNIX-based operating environment and a Windows-type graphical user interface. Functionality resident within Ocean's ADAWS Mod 1 (Colour Variant) system provides for tactical picture compilation, helicopter control, electronic warfare, and receive only Link 11 and Link 14. The system's four operator consoles are located in the operations room.
A combat system highway links ENA (via gateway nodes) with all other combat system member equipments. These include a full suite of navigation sensors and plotting facilities; a Type 996(6) E/F-band surveillance radar and LFA track extractor; two Type 1007 I-band radars for navigation and helicopter control; a Type 1010/1011 D-band identification friend or foe interrogator/ transponder; and an Outfit UAT(1) electronic support measures system. For close-range defence, Ocean is equipped with three Phalanx 20mm close-in weapon systems and two GAM-B01 single 20mm mountings (replacing the GCM-A03 twin 30mm mountings originally fitted). Soft-kill protection is provided by an eight-launcher Outfit DLJ(2) NATO Sea Gnat chaff/infrared decoy system.
The Amphibious Operations Room has a large screen display facility and five workstations for the EDS Defence Command Support System (CSS). Largely based on COTS information technology, the CSS is a fleetwide command, control, communications, computers and intelligence infrastructure designed to provide automated medium- and long-term planning support to the amphibious and ship's staff. It is employed to process, manage, disseminate and display the recognised maritime picture and other tactically useful information. Ocean has nine CSS workstations aboard (others are located in the Operations Room and the Warfare Office). Software for amphibious planning is in development; there are long-term plans to increase the CSS fit in Ocean to as many as 30 workstations.
The MCO is the main hub for all external communications, with facilities for LF/MF/HF, V/UHF and SHF satellite communications. Redifon MEL has supplied the main portion of the external communications suite for Ocean, adopting a hybrid solution that combines transmit/receive elements and combining system of the ICS6 suite (fitted to Type 23 frigates) with a distribution system largely derived from the ICS25 system fitted to RN mine countermeasures vessels and fleet auxiliaries. Externally, the system incorporates new AS6000 HF loop antennas in place of conventional whip aerials.
Park Air Electronics has supplied Outfit 1207 multi-channel VHF/UHF transceivers, together with an autoguard logger. Message processing and distribution is undertaken by DIMPS (supplied by British Aerospace Systems & Equipment), while Redifon MEL has supplied the RICE 10 internal communications and broadcast system.
One major new addition to service equipment aboard Ocean is the Operational Information System (OIS), a near-real-time information management system based on ruggedised workstations linked over a local area network. All of Ocean's dynamic data (heading, speed, pitch, roll and wind), together with aircraft lift, gun and rudder display functions are distributed and displayed via the OIS onto workstations and repeater displays located throughout the ship.
Ocean's Work Up Experience
"We've brought the ship out of build and proved that she can achieve what she was built to do in the original staff requirement," said Capt Bob Turner. "We must now begin to look ahead at what we want an LPH to do in the future, so we can best exploit her whole utility in peace and war across a whole spectrum of operations."
One issue is endurance. "The original operational requirement was predicated around a 42-day mission," points out Capt Turner. "A six-day transit, 30 days in theatre and then six days to get home. Today, we're deploying for four months, which means we must think carefully about sustainability."
He adds: "Ocean is very lean manned, and that calls for a new mindset. Innovative manpower management and meticulous planning of the watch and station bill have been needed to operate her effectively at sea. Nevertheless, sustainability and crew fatigue will need to be carefully monitored. We cannot be all things to all men.... There is not the strength in depth aboard to man up for defence watches in the traditional way. Similarly, for assault stations we must plan backwards precisely to ensure that we peak at the point of launch." [It should be noted that in early 2001 some crew members have been quoted in press reports as complaining that the ship is under manned.]
Ocean is a ship built to a tight budget. Commercial standards have been widely invoked to keep costs down, although this has brought with it some minor teething problems. "Excessive water expenditure was found to be a problem early on, the result of fitting screw taps and high-power shower heads," notes Capt Turner. "Those commercial fittings were incompatible with the military requirement, so we de-tuned the showers and replaced the taps with press-down percussion tops." He adds: "Four reverse osmosis plants were installed at build. We have now had a fifth installed to better cope with peak demands. Storage capacity has also been increased on board."
Overall, the application of commercial standard build practices and COTS equipments has been judged a relative success. "The early lessons have been and must still be fed into the LPD replacement programme to benefit both the procurement process and the new ships themselves," said Capt Turner. "Looking further ahead, CVF will also gain from our experience."
The single most significant aspect of the combat system identified for enhancement is communications. "Cost capping and assumptions on the availability of an accompanying LPD with full command, control and communications facilities mean the existing fit aboard Ocean is limiting for some of the tasks we may now be called upon to execute," said Capt Turner. "Bolstering the communications suite would give us the potential to improve our battle management capability yet further. "However, this should not mask the huge capability and potential that Ocean brings to the amphibious task group and the fleet. I believe that she is the right ship at the right time and represents excellent value for money."
In an assault landing operation, the first wave of troops are landed on the beach by landing craft from the LPDs - HMS Albion and/or Bulwark - and by a "vertical assault" on vital points somewhat inland by helicopters from the LPH (e.g. HMS Ocean), to establish a beachhead and landing zone. The LSD(A)'s are initially positioned about 20nm offshore and remain over-the-horizon during the first wave assault, they may use landing craft and helicopters to help offload the second wave and subsequent waves of troops and equipment from themselves. When the beach area and landing zone have been finally confirmed as secure, the LSD(A)'s will approach the landing zone and from just one or two thousand yards off-shore will deploy Mexeflotes (motorised pontoons) to assist in the quick and efficient offloading of the heavy vehicles and equipment that they carry. Once a harbour has been secured, Point Class "Ro-Ro" Strategic Transport's and ships taken up from trade (STUFT) will bring in further reinforcements and re-supply the force.
Links Note: Links open in new windows Janes
(The company's many publications are an excellent source of information
on HMS Ocean ) Royal Navy - HMS Ocean (all RN links deleted at
the request of the MOD) Last Update: 7 May, 2001
Note: Links open in new windows
Janes (The company's many publications are an excellent source of information on HMS Ocean )
Royal Navy - HMS Ocean (all RN links deleted at the request of the MOD)
Last Update: 7 May, 2001
© 2004-10 Richard Beedall unless otherwise indicated.