OPVs that come with lots of questions - UPDATED

Finally, the first steel has been cut for the first of three new Offshore (Oceanic?) Patrol Vessels for the Royal Navy. Ships which came quite out of the blue, and about which we began to know something only on the day of the ceremony for the start of building. But now work is ongoing and HMS Forth, HMS Medway and HMS Trent are the chosen names. The design selected, unsurprisingly, is a very mildly changed BAE 90 meters standard OPV already built. 


 
Of these OPVs we know that they are being built to "bridge a gap in workload" for the shipyards between the end of Block building for the aircraft carriers and the beginning of the construction of the Type 26 frigates. The MOD is locked into the financial terms of an agreement with BAE, BVT and VT groups, the infamous TOBA (Terms Of Business Agreement) which is (or better, we should probably say "was") about ensuring that the rationalized (read: reduced) shipyards left in the country are guarranteed a minimum amount of work each year, to enable their sustainment and the preservation of know how. The yearly workload to be sustained is quantified in around 230 million pounds worth of activities, and the MOD is bound to pay the shipyards to be idle, if activity falls beneath the baseline. The agreement was signed in 2009 by the Labour government with an expected validity of 15 years, renewable by 5 years intervals in absence of formal termination issued from one of the two sides.

The TOBA agrement(s) set out a way forwards for the preservation of shipbuilding capability, measured with the KIC (Key Industrial Capability) indicators, and set targets for cost cutting while having the MOD committed to ensure that appropriate work was always available across the yards. 
However, the Royal Navy has been cut back again and again in the meanwhile, and the deal has become unworkable as there are not enough orders anywhere to be seen to keep the yards going. The 2009 TOBA document for example contained open mention of what was to be the C1 combat ship, to enter service in 2019: the separated 10 C1 "high end" combat vessels and the 8 C2 "lower end" general purpose frigates have been cancelled and reabsorded into the Type 26 programme, hopefully for 13 hulls in total, and with entry in service moved back to no earlier than 2021 or 2022, with an obvious impact on the plans. MARS, the programme to renew the RFA, also ended up being far smaller and far different than what had been imagined back then. 

In November 2013, the conservative government renegotiated costs for the Queen Elizabeth class and shaped out a deal on the way forwards that effectively "suspends" the TOBA agreement thanks to the OPV order, and eventually leads to the end of the TOBA. Shipbuilding in Portsmouth ends, with only a partial compensation coming thanks to renewed investment in the support, maintenance and refit infrastructure, including renovation of dock 15, a planned revamping of dock 14 and the bonification of 3 Basin to enable underwater maintenance. Even so, it is increasingly looking evident that Govan shipbuilding will cease as well, with 200 million pounds invested in improving Scotstoun to make it a one-location "frigate factory" hopefully able to build ships at far more competitive prices. 

Faced with some 230 million pounds of payments to make to BAE in absence of work between 2014 and 2016 (end of Block building for the Prince of Wales aircraft carrier and planned first steel cut for the first Type 26), the MOD correctly decided to instead order the building of some vessels, to actually preserve skills and to get something tangible out of the sizeable payment. 


Weird cost figures

There is, therefore, a challenge in sustaining a skilled shipbuilding work force in the United Kingdom between the completion of construction of the blocks for the second carrier and the beginning of construction of the Type 26 in 2016. Under the terms of the TOBA, without a shipbuilding order to fill that gap, the MOD would be required to pay BAE Systems for shipyards and workers to stand idle, producing nothing while their skill levels faded. Such a course would add significant risk to the effective delivery of the T26 programme, which assumes a skilled work force and a working shipyard to deliver it.

To make best use of the labour force, therefore, and the dockyard assets, for which we would anyway be paying, I can announce today that we have signed an agreement in principle with BAE Systems to order three new offshore patrol vessels for the Royal Navy, based on a more capable variant of the River class and including a landing deck able to take a Merlin helicopter. Subject to main-gate approval in the coming months, these vessels will be constructed on the Clyde from late 2014, with the first vessel expected to come into service in 2017.
The marginal cost of these ships, over and above the payments the MOD would anyway have had to make to keep the yards idle, is less than £100 million, which will be funded from budget held within the equipment plan to support industrial restructuring.

Secretary of State for Defence, Philip Hammond; statement to the House of Commons, 6 Nov 2013 : Column 253


230 millions however, turned out not being enough. The order for three OPVs required some 100 additional millions, bringing the total to 348, as from the contract signed in August 2014, inclusive of 20 million expended in March 2014 for long lead items. 

This is where the first question arises. 348 million is quite a lot of money for three vessels which are as basic as they could be, and only come with 29 secondary design adjustements compared to the BAE 90 meter OPV design already built in three examples in the UK and in one example in Thailand, on BAE licence. 

The three 90 meter OPVs built in the UK were constructed under a 2009 contract, worth 155 million pounds, signed by the government of Trinidad and Tobago with then VT Group. The OPV order came in the two years (2007 - 2009) over which BAE negotiated and then concluded a joint venture with VT which actually saw BAE buy the VT Group's shipbuilding activities. 

The Trinidad and Tobago deal fell apart in 2010, even with the first two ships being already ready for delivery. The then Port of Spain class was suddenly without a buyer, and the vessels were left in Britain while BAE and Trinidad sought a settlement. Eventually, Trinidad and Tobago agreed to allow BAE to seek a new customer for the ships, and in 2011 Brazil stepped in, eventually purchasing the whole trio as the Amazonas class with a 133 million pounds order placed in 2012, which also included some support and the licence to build up to five more vessels in its own yards.
2012 also saw the legal settlement between BAE and Trinidad. Trinidad and Tobago officially claims to have won the legal battle on the basis of delays in the construction of the ships and in "defects" they reportedly had, and the Trinidad government says it got almost 1,5 billion Trinidad dollars in payments. That means BAE paid Trinidad some 125 to 130 million pounds. With the money it got from Brazil, BAE avoided the loss, but made nothing out of the three ships. 

Today’s settlement is likely to be for £125m-£130m. There should be a net nil result in the working capital for the year as we understand Brazil has already paid for the ships

Financial Times report

The fourth vessel of this type was built abroad under licence: the HTMS Krabi of the Royal Thai Navy was built by the Mahidol Adulyadej Naval Dockyard, in Bangkok. Laid down in August 2010, it was launched 15 months later, on 6 December 2011. 

The vessel is built with some significant enhancements: the main armament is an Oto Melara 76 mm gun, with two DS30 30mm guns as secondary armament, combared to the Amazonas which have a 30 mm and two 25 mm guns. The Krabi has its flight deck thought for AW-139 helicopter operations.

The combat systems are different, but the main sensors are pretty much the same. 

The cost of the Krabi was 2.8 billion Baht, equating to some 54 million pounds, more or less. 

The four OPVs in the class built so far have had a cost ranging from 44 million pounds (Brazil deal) to 52 million (original Trinidad and Tobago price) to 54 million (Thai example). 
The three to be built for the UK come with a 348 million pricetag: 116 million each. 

Looking abroad, the cost comparison continues to be painful: the british OPVs cost far more than those, of similar size and comparable performances, being built for Ireland by Babcock (some 50 million euro each, around 40 or so million pounds); they cost far more than the Otago for New Zealand (90 million NZ dollars, or 45 million pounds, with hangar and work area in the stern) and they don't stand any comparison with the Holland class built on the other side of the Channel, which in my opinion, for their price, represent the best deal possible.  


Why the cost difference?

The cost difference is pretty much certainly not coming from the vessels themselves. The Royal Navy examples come with some 29 changes in the design, but none of these can quite justify such a cost difference. 
The Royal Navy ships will have the same hull and propulsion as the earlier BAE 90 meter OPVs. Range is a bit uncertain as Navy News at one time was quoting 6300 nautical miles, but generally the figure given is 5000 to 5500 nautical miles, the same as the other vessels in the class. Speed is again the same, and indeed the engines are pretty much certainly going to be the axact same as on Amazonas. 
The main radar is a SCANTER 4103, and all vessels in the class have a 4100 series. The Royal Navy example will have a Kelvin Hughes SharpEye navigation radar, reinforcing the feeling that the SharpEye is the RN's pick for the incoming renewal of the fleet's range of navigation radars (replacement of Type 1007 I-band radar; of the Northrop Grumman Sperry Marine Radar Type 1008 E/F-band radar, and of the Raytheon Radar Type 1047 I-band and Radar Type 1048 E/F-band radars, from 2016. Programme known as Navigation Radar Portfolio, ex NASAR project (NAvigation and Situational Awareness Radar), which had aimed for a 2012 ISD but was delayed). SharpEye had earlier been selected for the Tide class tankers (three such radars will be on each tanker), and has been installed on RFA Argus to control helicopter operations, while on Fort Rosalie it has been experimented in detecting and tracking FIAC threats at sea.

The main design changes include a reinforced flight deck capable to take a Merlin helicopter (the Amazonas have a flight deck capped at 7-ton class helicopters) and an improved Helicopter In Flight Refueling equipment, to support helicopter operations. 

HMS Clyde during HIFR operation with one of the two Sea King SAR based in the Falklands

According to Jane's, the other differences are:

an International Maritime Organization-compliant sewage waste treatment plant; additional accommodation for embarked military detachments; and improved watertight integrity and firefighting provisions to meet Naval Authority standards.

Jane's report 

The additional accommodation is tricky, because it is hard to see where they could put it, since the ship has exactly the same sizes, but a larger and reinforced flight deck and larger HIFR fit, i'm guessing with more fuel for helicopters, as well. Space is not going to magically augment. In fact, the BAE and MOD accommodation data suggests that there is no increase at all from the Amazonas: actually, possibly a reduction of 10, from a maximum of 70 to a maximum of 60, of which 34 / 36 base crew and some 24 EMF / helicopter flight. Almost certainly, the "additional accomodation" is said with reference to the River Batch 1 in current Royal Navy service.

The ships have two Pacific 24 RHIBs and the 90 meter BAE design offers the possibility to embark up to 6 20' containers, two of which should be carried behind the RHIBs, while to carry the other four it is necessary to use the flight deck, and so negate helicopter operations. 

A scheme of the flight deck, with 4 TEU containers arranged on deck within crane reach. Another seems visible in the bottom left corner, meaning behind the RHIB, and another might be on the other side, again behind the RHIB.

 
Armament on the RN variant is one DS30M 30 mm remotely operated gun turret and two MK44 7.62mm miniguns on the sides of the bridge, making it the lightest armed variation of the 90 meters family. Not surprising, but still worth of notice. 

A written answer given to the House of Commons details the 29 changes, one of which has been dropped from the requirements:

1 Watertight Integrity Modifications
2 Fire Safety Modifications
3 Enhanced firefighting facilities
4 Automatic Emergency Lights
5 Flight Deck Officer Position
6 Domestic refrigeration Modifications
7 Sewage Treatment Plant Modifications
8 Exhaust System Modifications – (No longer required)
9 Ballast Water Modifications
10 Merlin helicopter operation
11 Helicopter In-Flight Refuelling
12 Helicopter refuelling modifications
13 Changes to ship’s minimum operating temperature
14 Davit Modifications
15 Force Protection Weapon Modifications (lose two 25mm gun turrets, replace with MK44 7.62mm gatling)
16 Install WECDIS/WAIS
17 Install Combat Management System      (better expressed by saying they are to replace the existing combat system with the OPV version of the BAE Surface Common Combat System infrastructure which has been installed on HMS Ocean and is due to appear on all other ships in the RN fleet)
18 Military communications modifications
19 Magazine Protection
20 Radio Equipment Room Modifications
21 Change lighting and domestic power voltage from 115v to 230v
22 Codification of equipment
23 Provision of life saving equipment
24 Replace navigation radars      (The River Batch 2 gets the Kelvin Hughes Sharpeye, which seems set to become in 2016 the fleet-wide replacement for the Type 1007 after being also selected for MARS FT and fitted to Argus and Fort Rosalie)
25 Install Military GPS
26 Install flight deck landing grid
27 Fuel efficiency monitoring
28 Provide emergency communication equipment
29 Machinery Space Walkway


The 2017 handover date to the Royal Navy does make me think that part of the higher cost is due to the work being done with the brake pulled. These ships can be built in some 15 months, normally, and this would mean launching the first, HMS Forth, by the end of 2015. More than a year for fitting out and delivering such a basic OPV really seems too long a time, so we might be in for a stretched out build. 
The question then becomes one of ripple effects on the Type 26 programme: the first steel cut for the first new frigate is expected in 2016, with block integration beginning in 2017. Even at 15 months per ship, there should be a significant overlap, depending on how much of the OPV work goes on at the same time. 
It would be nice to have greater details on the expected building schedule. And in the meanwhile, we are left to hope that we aren't staring at an hidded schedule slip for Type 26. 

A skills and jobs saving measure? 

Avoiding a short (at least if Type 26 isn't delayed) gap in shipyard work with an expenside order, paying three ships more than due in order to keep the yards alive might not be a bad investment IF there is a clear way ahead after this gap-filler. The 2009 plan, fixed with the TOBA, fell apart incredibly quickly, and big questions remain to be answered about this new course.

Observing the MOD plans (even bearing in mind that changes and cuts are a constant...) we have:
 
- Main Gate for Type 26 frigate expected at the end of this year with building of the first vessel expected to start in 2016. 13 vessels to be built, with the first entering service in 2021 and the last not before 2036;
 
- MARS Solid Support Ship: while the MARS Fleet Tanker requirement has been met ordering hulls in South Korea on the ground that tanker hulls are simple and are best built by yards which build commercial tankers all the time, the assumption is (was?) that MARS Solid Support Ship, being more complex and technologically sensitive, would be built in british yards. The Fort class supply vessels are due out of service in 2023 (Fort Austin) and 2024 (Fort Rosalie) and undoubtedly Fort Victoria is also planned to bow out roughly in the same timeframe (2025, possibly?), so the replacement vessels have to enter service in the early 2020s. If they are to be built in Britain, and now doubting of it is licit, they will overlap with the work for the Type 26 frigates.
 
- MHPC: in late 2012 a DSTL document said that the MCM, Hydrographic and Patrol Capability programme should deliver the first new vessel in 2028. MHPC will replace the Hunt and Sandown minesweepers and, possibly, the hydrographic ships HMS Enterprise and HMS Echo. HMS Scott and her oversized equipment are unlikely to be replaceable by the relatively small multipurpose vessel (some 3000 tons, according to most sources) envisaged for MHPC. Delivery of the first vessel in 2028 implies an overlap with the activities on the late Type 26 ships, which will continue to be built into the 2030s.

One day, RFA Argus and RFA Diligence will have to be replaced, as well. They have been hard worked ever since they were picked up from trade in 1982 for the Falklands war, and in the 2020s it'll become increasinly necessary to find solutions for their replacement. A Maritime Role 3 Medical Capability vessel (MR3MC) is a requirement and a wish ever since the Labour defence review in 1998, but progress has actually been null. Studies for the Future Repair Capability have also lead nowhere so far. 

Very rough recent concept vessels, apparently based on the hull of the MARS Solid Support Ship variant, itself still in concept phase. In 2008, the OMAR concept by BMT was presented as an interesting solution to replacing Diligence. Who knows how many more years will have to pass before anything is built. If anything gets built at all, of course.

In theory, there is plenty of work on the horizon. In theory. It will be interesting, but probably, looking at recent history, also very unpleasant, to see how things will evolve, how many ships will actually be built, and where.

The boat building activity in Portsmouth is expected to survive the closure of the major surface warship activity. Of interest in this field we have the Royal Marines requirements for a Fast Landing Craft, which has however been put on hold and won't resurface before 2020, when the slow LCU Mk10 is supposed to finally retire; and the requirement for a Force Protection Craft. The fate of this second Royal Marines requirement is not clear at the moment. During DSEI 2013, CTrunk, while unveiling its THOR catamaran solution for riverine, force protection and inshore mission, said that they were in contact with the MOD, which hoped to reveal its final requirements for the boat during 2014, but so far there is no evidence of progress.
The Force Protection Craft programme, at least until 2011 or early 2012, hoped to deliver 12 crafts, which would partially replace the current fleet of 21 LCVP MK5s, from 2016.

Perhaps the most important measure of success or failure of the OPV stop-gap order will be the Type 26 programme: keeping the line hot and the skills intact absolutely has to ensure a smooth programme for the new frigate, with ships launched on time and on budget, because otherwise both the industry and the navy will be in serious, serious trouble. 



Have ships, will sail?

In the short term, while still wondering exactly why these three OPVs are costing so much, i believe there is one imperative: getting the greatest return possible out of a combined 387 million expenditure in OPVs. 

The unpleasant bit of news about the River Batch 2 is that they are expected, at least for now, to replace the River Batch 1 OPVs. These cheap and effective vessels have only been purchased outright from BAE in 2012, for 39 million pounds. Initially, in fact, the three ships were not owned by the Royal Navy, but they had instead been built under an arrangement with the shipbuilder, Vosper Thornycroft (VT), under which the Royal Navy leased the vessels from the shipbuilder for a period of ten years. VT were responsible for all maintenance and support for the ships during the charter period. At the end of this, the Navy could then either return the ships, renew the lease or purchase them outright. The first lease period was renewed in 2007, out to 2013. In September 2012 the outright purchase was announced.
The oldest one was only launched in 2002, so in 2017, if replaced, would bow out after a mere 15 years of life and just 14 years of service, having been commissioned in 2003. In my opinion, this is shameful and can't be allowed to happen, especially not in a Royal Navy already struggling to cover its basic, daily committments.

The new ships will be extremely welcome and useful if they are kept in addition to the Rivers, so that they can fully exploit their increased capability and potential by being employed away from home waters, to offload some constabulary tasks from the high end part of the fleet.
The Rivers will be barely around 14 years old when the first new ship is delivered, in 2017, and the Royal Navy has a clear need for deployable hulls. The new OPVs, with their greater sizes and capability (including helicopter) can and should be used away from home, to relieve the frigates of some of their tasks (Caribbean, but also counter-piracy, for example), while the River continue to do what they have done well for years.

Not long ago, the government published its Maritime Security strategy. The document, while being of some interest, hardly deserves the praise it received from several commenters. Moreover, the supposed "strategy" is written out in a deliberately ambivalent, vague way, especially when it comes to the new OPVs: mentioned several times in the document, they are described as a "further improvement" to the UK's maritime security capability, but not once there is a clear statement of their fate, and that of the Rivers. The official line is that the decision is left for the next SDSR. Of course.
The document has been written in such a way to allow the government to bin the Rivers and still describe the situation as an "improvement" because of the greater capabilities of the new vessels, regardless of the fact that, observing historical trends in the use of the Rivers, it is safe to say that such additional capabilities would be hardly be needed, and will only sparsely be exploited.

HMS Tyne, HMS Severn, HMS Mersey

There is no real operational reason why the Rivers need to be urgently replaced by larger OPVs with aviation landing facilities. While additional capability is always welcome, it should not come at the cost of the Rivers. The Rivers are not combat vessels: they patrol the economic zone of the UK and control that fishery respects the rules. They are very busy ships and they are very precious in forming the officers that will then transfer to the large warships. But they have little to no combat use, they are tied to home waters and they do not really need aviation facilities that would be seldom used at best. A flight deck could be handy to operate small rotary wing UAVs, perhaps, but a Camcopter does not take a Merlin flight deck, and i'm pretty sure that enough space could be arranged in the stern of the current Rivers, if that was the idea.
The new OPVs announcement, in other words, as it has been made, smells of back-door capability slashing. The Merlin-capable flight deck immediately made me imagine an horrible scenario in which know-nothing MPs with little understanding of the military are made to think that the ability to refuel a land-based Merlin helicopter away from the shore using the OPVs is a replacement for the missing Maritime Patrol Aircraft capability, for example. Most obviously, for a tons of very good reasons, this wouldn't even rank as mitigation of the gap, and never could it be "a replacement".
The Rivers are very busy in their intended role, besides, and the replacement vessels would be just as busy, meaning that they would actually have very little chance to even try and use their greater capabilities, which in home waters are useful, at best, but not essential.

The Fishery Protection Badge, approved recently by the Navy

The Fishery Protection Squadron is constantly out at sea around the UK, and has very little, if any time to wander far away from home. A 42 strong crew is embarked to work to a three watches mechanism. Each ship has an additional allocation of personnel used to rotate members of the crew to meet harmony rules. Personnel on the Rivers could be indicatively expected to spend four weeks at sea and two weeks on land, pretty much all year long. The River batch 1 ships each spend a minimum of 275 days out at sea, with maintenance to the vessels intended to ensure the capability of spending up to 320 days at sea. Normally there is a 9 days maintenance period and a longer one of 16 days, each year.
Combined, the three ships have to deliver at least 700 days of activity at sea, and Hunt minesweepers are used to complement the Rivers in fishery protection patrol task, but with no fixed target. Back in 2004, some three Hunt vessels could be routinely expected to be involved in supporting Fishery Protection. 
The only way in which the new OPVs could go "tackle piracy" as has been suggested, while replacing the Rivers, is reducing the fishery protection coverage in home waters. There really is no excess availability.

And having a Merlin-flight deck is of little use when the availability of spare Merlin helicopters is going to be next to none, with just 30 of them being retained (although recently news reports told of the Navy's battle in the background to get funding to upgrade to HM2 up to 8 more, as once had been planned) and all of them already overtasked, especially with the AEW role falling on them as well, under CROWSNEST. 
One thing for which the large flight decks could be useful is for landing the S-92 and AW-189 helicopters of the civilian SAR service coming up, to refuel them and enable them to expand their reach out at sea, but even this might be an illusion as it is unclear if the PFI-supplied crews will even have any deck-landing certification.

Cooperationg between the River batch 1 and the military SAR helicopters is pretty common, but despite my research, i haven't been able to verify if HIFR is an option available as of now. Another question without a certain answer is whether the incoming civilian SAR crews will be able to make any use of HIFR and even of helicopter decks on ships at sea.

MP Bob Stewart has, admiradly, thought of the same thing, but still we have no precise answer on whether that would be possible. The helicopter could surely use the deck, but would the crews be qualified for it? That's the real question. Besides, the Rivers do have a large cargo deck in the stern, which might be at least fitted with HIFR equipment to refuel helicopters without having them landing (i've been unable to verify if the Rivers already have such a capability). 
The cargo deck of the Rivers adds flexibility of its own as it can be used to carry containers, an LCVP, or pollution containment equipment, or other cargo, but it might be also adaptable to take helicopters, since HMS Clyde can, and isn't much different in design, nor much longer. 
The fear is that the new OPVs will not just take away the Rivers early, but be used to unrealistically run down other capabilities as well: 
 

Bob Stewart (Beckenham) (Con): Most people suggest that our biggest defence capability is not in maritime patrol aircraft. I am no expert—although I can see that there are many naval experts in the Chamber—but could this new River class OPV, with its enhanced length and helicopter deck, also be used to cover the gap between 240 nautical miles, the distance a land-based helicopter can go out from our shores into the Atlantic, and the 1,200 nautical miles for which we are treaty responsible? Could it perhaps play some sort of MPA role in that area?

Mr Hammond: I have not looked at the specification in detail, but I do not envisage that the thing will be able to take off and fly. I understand the point that my hon. Friend is making, however, and we are conscious of the gap in maritime patrol aircraft capability. It is one issue that will be addressed in SDSR 2015 and we will manage the gap in the meantime through close collaboration with our allies. We are considering all the options, including, potentially, the use of unmanned aerial vehicles in a maritime patrol role in the future.

Note how, as i feared, irrealistic mentions of MPA capability are made. Back-door capability cutting, camouflaged as new capability being delivered. Disasterous, and tipically suited to politicians. Better to keep one hunded eyes open on this matter. 

In other words, there is no real need to replace the Rivers with these new vessels. Losing the current River vessels would be a waste, and the greater capabilities of the replacements could also end up largely wasted.
In fact, these new vessels would be perfectly suited for interdiction of smuggling, for protection of oversea territories (And the Caribbean standing task springs to mind) and counter-piracy work as well, as noted by Hammond himself in answer to a question by Peter Luff:  

Peter Luff (Mid Worcestershire) (Con): I commend the Secretary of State, the Minister for defence equipment—the Under-Secretary of State for Defence, my hon. Friend the Member for Ludlow (Mr Dunne)—the Chief of Defence Matériel and all those involved for making the best of a very difficult situation. Will my right hon. Friend clarify the purpose and capabilities of the three new very welcome offshore patrol vessels?

Mr Hammond: They will be more capable than the existing River class, as they will be able to take a larger helicopter and will be 10 metres longer. They will be able to undertake a full range of duties, including not only fishery protection but the interdiction of smuggling, counter-piracy operations and the protection of our overseas territories.

To do all that, though, the new vessels would have to sail far away from home and, most likely for it to have any sense, they would have to be forward based, like HMS Clyde in the Falklands. While the OPV is suited for ocean navigation, it has a short logistic endurance in terms of stores (little more than one month for the new vessels) and, in part, in terms of fuel, so that sailing it back and forth from the UK would not be particularly effective. The BAE 90 meter OPV can be refueled and restored at sea, but the less this is needed, the better, as it keeps pressure off the RFA.
The new OPV would be a perfect solution for the West Indies committment, if it was forward based there. If the ships end up home-based, and tied to the River's current role, they won't be able to do anything of what they could and should do. 

In my opinion, the Royal Navy can obtain an excellent boost in capability if it manages to retain the Rivers for fishery protection and home waters, using the new vessels in addition, forward-basing them overseas. I can think of three locations:

Caribbean, removing a committment that has been a source of problems and embarrassment for the Royal Navy which has long struggled to find a way to send a warship, having to resort extensively to RFA vessels which would also be very much needed elsewhere, for their actual role. 



Gibraltar, because from the base the OPV would be able to engage with allies, with North and West African countries while also providing much needed reassurance to the Gibraltarians, which are loudly calling for a more tangible sign of UK support

Bahrain, because the OPV would be able to provide additional anti-FAC protection to the minesweeper squadron there and/or deploy to piracy-infested waters, restoring more enduring british presence in the wider area and relieving the warships from another role which has been hard to cover with a sheet which is, at the moment, just too short.



UPDATE: several comments have underlined the limitations that come with the lack of a hangar, and with a ship with limited space and accommodation for Hurricane season support. They are both valid points, and very real issues. I've decided to add a short section here to say a little bit more about how these problems impact the use of an OPV in the Caribbean. 
The lack of a hangar is the most evident sore point of this design. And it is a major limitation for long missions abroad. However, there might be the possibility to remedy to the problem later on, with the addition of a telescopic hangar, which would come forwards over the flight deck, covering and protecting the helicopter when not in use. Notable examples are the italian navy OPVs of the Comandanti class, although their telescopic hangar is relatively complex and well integrated in the superstructure, while the design of the 90 meters OPV, with a low and small read superstructure block surmounted by a crane is more problematic.

A telescopic hangar could help solve the major issue of these OPVs, although the shape of the superstructure is not very friendly

 

In this line drawing my MConrads and Enrr, the italian navy OPVs can be seen with their telescopic hangar deployed and retracted. It is the only way to obtain hangar protection in ships which don't have enough space to have a flight deck and a hangar at the same time. 

Unless the superstructure is more widely modified and the crane relocated higher, the addition of a telescopic crane will have some impact on the ability of the crane to turn all the way back to load and unload large payloads onto the flight deck. 

Side plan from the BAE video. Note the crane extended. The addition of a telescopic hangar would put a bulky frame in the way, and impact the freedom of movement of the crane and, at least in part, the ability to embark TEU containers on the flight deck. Still worth it, i'd think.

 
Regarding the typical missions in the Caribbean, the OPV would be well suited to patrol and counter-smuggling. For the Counted Narcotics and Terrorism (CNT) mission, Royal Navy ships embark a ship flight and a US Coast Guard LEDET (Law Enforcement Detachment) of some 10 men. Greater accommodation wouldn't hurt at all, but the OPV should be up for it. 

Hurricane season relief is more of a problem. A normal Humanitarian Assistance and Disaster Relief (HADR) package on a "Hurricane Season" these days is an RFA vessel with a 20 men (or larger) RN HADR team, supplemented by 30 or so men taken from the RFA crew. An helicopter flight is also desirable, obviously, and space for stores is also needed. An OPV this small can't do very well in this mission. However, an enduring OPV presence in the area would still be able to remove some pressure on the RN core fleet, and a more suitable HADR platform, undoubtedly a large RFA vessel, could still visit during the crucial hurricane months (August, September and October) and be made available to some degree over the lenght of the whole hurricane season, which officially goes from June 1st to November 30. 

Despite the limitations of the design, the new OPVs could still be very useful. 
The challenge of retaining them is, of course, in budget and manpower. The Royal Navy is exceptionally lean-manned, following the latest cuts. The insufficient manpower is possibly the biggest problem that must be overcome to bring the second aircraft carrier into service alongside the first, and trying to man three new patrol vessels as well, even with the crews being pretty small, is not going to be straightforward at all.
In terms of cost, the River class costs annually just about 20 millions per year. More correctly, it did in 2010: the current value is probably different. The outright purchase of the vessels has been made in the assumption (hopefully supported by facts) that removing the lease costs would reduce the annual expenditure, while further differences are likely because of inflation and other factors. Anyway, we are talking of a very small amount for three very useful vessels with plenty of life left in them. The new OPVs will also be hopefully quite cost-effective, so the Royal Navy should make every effort to secure all six in the longer term.

The door for such a decision, at least in the words, is left open:

Mr Julian Brazier (Canterbury) (Con): I, too, pay tribute to my hon. Friend the Member for Portsmouth North (Penny Mordaunt) for her doughty struggle to get a good city deal for her constituents and for the vision for the OPVs that to my knowledge she has been outlining for at least two years. Will the Secretary of State confirm that the OPVs will to some extent provide a force multiplier for our frigate fleet? Some of the roles carried out by frigates do not require full frigate capability, so the OPVs could be a way of partially expanding that capability.

Mr Hammond: At the risk of causing her to blush, I am happy once again to praise my hon. Friend the Member for Portsmouth North. I should say to my hon. Friend the Member for Canterbury (Mr Brazier) that no decision has yet been taken about whether the old River class vessels will be retired after the new OPVs are brought into service. That decision will have to be made in SDSR 2015 based on the ongoing budget challenges of maintaining additional vessels at sea. That will be a decision for the Royal Navy.

This is somewhat reassuring, as well as the admission that there has not been a decision on where to base the new OPVs. If they were already certainly meant as a replacement for the Rivers, the basing answer would be pretty simple.
Of course, the door is not locked, but this does not make it easy to push it wide open and squeeze the new ships and the old ships through. I can only hope that the Royal Navy realizes how decisive the next SDSR is going to be for its future, and i hope people is hard at work, already now, to make sure to fight the incoming battle with the utmost determination.

Any possible solution should be actively considered. To overcome the manpower issues, it might be attractive to use RFA manpower, but we must not forget that the SDSR took away 400 men from it as well, leaving it far from being overmanned.

Another chance, which has the favor of government, is the use of reserve personnel. This is the only area that is seeing a manpower increase, and it is also low-cost manpower compared to regulars, so it might be very helpful to find ways to fill as many posts as possible on board of the OPVs with reservists, even though it is challenging: normally, a crew member on a River stays onboard for four weeks and then rotates ashore for two weeks, while the ship is at sea for most of the year. Finding a way to make good use of reserves in this cycle could be challenging. 

These new OPVs are an option for having a little bit of a two-tier fleet. It is a concept that has long made First Sea Lords nervous, as they seen the constabulary ships as a threat, in the funding battle, to the high end part of the fleet. Most recently, first sea lord Zambellas, speaking in the US, went on record reinforcing that mantra:

“You aim for high end and you accept the risk your footprint’s reduced globally… I absolutely reject the idea of an ostensibly [larger] number of smaller platforms that might have a wider footprint.”

Yes, the Sea Lord said, the UK could invest in what’s called a high-low mix, buying many cheap ships suited to “constabulary” operations off Somalia and a few expensive ships in case of major war. “The danger with that is when you are needed to perform a high end — and therefore a strategically valuable — task alongside a partner, you find that your low-end capability doesn’t get through the gate,” Zambellas said. “You lose out on the flexibility and authority associated with credible platforms.”

Breaking Defense report 

However, these ships are coming. If it was about starting a programme out of the blue to purchase "constabulary" small vessels in addition to frigates, the First Sea Lord would have every reason to be worried, and hold back on such a project, as a budgetary battle would undoubtedly follow, with the Treasury questioning expenditure on high end warships, with negative effects.
But there three OPVs by now are on the way, and the Rivers are already in service. To preserve shipbuilding in general, the Batch 2 is being built, and once they arrive, they must be used to best effect. I understand the worries of the First Sea Lord, but at the same time i must underline that in recent times the "all high end" policy of the navy just isn't working. There are too few high end platforms to respond to any unforeseen event. When an operation starts somewhere, or even just when the navy fields its most important asset, the Response Force Task Group for the yearly training deployment, the high end warships simply aren't there, because they are all tied down into standing tasks duties. Either some standing tasks are removed, or the navy needs more hulls.
Libya in 2011 was an example: it took ships that were coming back home to be decommissioned and a temporary gapping of the presence in the South Atlantic to put ships in the area of operation. This, to me, does not look like a good result. 
The Cougar deployments and Joint Warrior exercises should be the Navy's apex in peacetime, and should see the presence of all relevant capabilities, and of as many high end warships as possible so that said vessels and crews can be tested and prepared for the operations that actually require their capability. Instead, this is not possible. Cougar 14 represents rock bottom, with no british escorts to be seen. Cougar 13 managed to snag some frigate support by exploiting the fact that Type 23 in the Gulf needed replacement, and so one frigate sailed with the task group while heading there. 
Type 45s haven't yet been able to attend a single Cougar deployment. 

These three OPVs, built not for a real requirement but for helping industry, do represent a huge potential help for the fleet. They might be simple and uninpressive "cheap" (not really, as we saw) vessels, but if assigned to the right areas and constabulary tasks, they could allow some more high end warships to serve as warships and actually prepare for the high end, complex ops they were built for. They have a potential that goes far, far beyond their size and their own weapon fit. Even without a hangar (the limitation, by the way, that i find most displeasing, although it was known all along) and with just a 30mm, they can increase british presence in some areas where the full might of a frigate or destroyer isn't necessary, thus enabling these to deploy elsewhere, on more challenging tasks.

In conclusion, while giving work to the yards is the right thing to do, i urge the government of the day, whatever it wll be, and the Royal Navy and industry, to take a very, very careful look at things. A long term plan is needed. Funding is needed. And industry must get better at what it does. I'm a huge supporter of british shipbuilding, but i am not a supporter of wasting money. It isn't even my money, but i'm still against it all the same. The pricetag of these vessels is a shame, period. I do assume that the pricetag includes plenty of expenditure non related to the OPVs itself. I'm assuming it is money needed to get out of the TOBA agreement, but i sincerely hope we will be explained why and how this cost figure came together. It is a lot of money for these particular three ships. 
If there are good reasons, and this is a fundation for a better, stabler shipbuilding in the future, it will still be money well spent. Otherwise, frankly, if it turns out that british shipbuilding doubles the cost of even the simplest of OPVs, perhaps it is indeed time it dies, so the navy can be equipped at half the price, and what is saved can be invested to create jobs in other industry sectors where the same hundreds of millions are likely to put into employment a higher number of people. I will sound like a bastard, but it must be said. It is a simplification of the concept, but the general idea is that shipbuilding capability is precious and is worth overpaying for, but only to a point. When it becomes damaging for the Navy that can afford less vessels, and for jobs which require too much money to stay around, and in ever decreasing number no less, it is time to stay stop.