The Type 45 destroyer is often regarded as the most advanced guided missile destroyer in the world.

‘To operate safely at sea, the Royal Navy must protect its ships from attacks from the air’

National Audit Office, March 2009

Indeed, during an ‘intensive attack’, a single Type 45 could simultaneously track, engage, and destroy more targets than 5 Type 42s, its predecessor, could.

Despite it’s extraordinary capability, the Type 45 has as I’m sure most reading this are aware, a fairly substantial problem.

A brief history lesson

The Type 45 began with the imaginatively named NFR-90 (NATO Frigate Replacement for 90s). The project intended to take advantage of economies of scale and provide nations including the UK, US, Canada, and Spain (full list here) with a frigate.

The project ultimately collapsed when the UK and US withdrew, both worried that the new frigate didn’t have the capabilities they required.

The UK then joined France and Italy in a new programme: the Horizon-class frigate. This also collapsed in 1999 due to disagreements regarding workshare.

Finally, the UK began development of their own programme, with the first ship planned to enter service in 2007 (Daring was in reality commissioned in 2009).

The problem

The Type 45 is powered by the Rolls-Royce WR-21. The engine can interestingly no longer be found on the Rolls-Royce website, likely due to its issues (it can however be found using a web archive here).

‘The WR-21 engine incorporates revolutionary enhancements in gas turbine technology to reshape the traditional gas turbine performance curves and produce long term fuel savings’

Archive of Rolls-Royce website

The WR-21 was designed alongside Northrop Grumman. I’ve also been told by a defence source that the engine ‘was meant to be a UK-US joint programme (the W stands for Westinghouse) but the US then didn’t use it in the ships they were going to’.

The issue with the engine is the ‘intercooler-recuperator’. This should in theory recover heat, making the engine more efficient and crucially, reducing the ship’s thermal signature.

Unfortunately, and there’s no better way of saying this, it doesn’t work properly. When it fails, the diesel generators can ‘trip out’, leaving the ship with no electrical power or prolusion.

How did this happen?

Back in 2000, the then Secretary of State for Defence Geoff Hoon had to select the engine that would power the Type 45. BAE Systems ran a competition, with Rolls-Royce putting forward their WR-21, and General Electric their LM2500.

‘The LM2500 family of aeroderivative gas turbines boasts more than five times the operating experience of its competitors combined, and its flexibility and reliability are unsurpassed’

General Electric website

The LM2500 is derived from the General Electric CF6, an aircraft engine used on the Boeing 747 and Airbus A330 among many others.

More than 2,200 units of the marine version have been sold, with 15m hours in marine operation. Over 30 world navies using the engine.

To see the full scale of this lunacy, visit the Wikipedia page to see the list of ships that use the engine.

Rolls-Royce on the other hand are rather less vocal about engine numbers. We know no other ship in the world uses the Rolls-Royce WR-21. We also know there are six Type 45 destroyers, each with two engines. Assuming there are a few spare, there are at most 20 of the WR-21 engine.

When Geoff Hoon announced the government had selected the WR-21, he conceded that it posed “a greater degree of risk to the programme” than the LM2500. Ultimately however, he credited “a range of other factors” as favouring Rolls-Royce; it is widely accepted that the decision was taken to support UK jobs.

The verdict

The Type 45 was presented with two potential engines. The General Electric engine was ‘tried and tested’ at the time, and in the decade since, has proven remarkably reliable for the world’s navies. Had BAE Systems or the Royal Navy been allowed to choose, I see it as highly likely they would have chosen this engine.

The Rolls-Royce engine was untested, and had been hastily designed to be ready in time for the competition deadline. No other world navies showed any interest in it.

And yet, the politician chose the Rolls-Royce. I hate to scapegoat individuals, and indeed it is hard to know how much of the decision was his. However, to choose the engine for a naval destroyer based on supporting UK jobs, rather than reliability and capability, seems extraordinarily short sighted.

The decision was out of the Royal Navy’s hands. Industry level decisions on UK procurement tend to be made politically. Nonetheless, it is the Royal Navy who are suffering as a result.

‘Replacing the existing two diesel generators, fitting an additional diesel generator and modifying the high voltage system on each ship’

BAE Systems on the what the PIP entails

In March this year, the MoD announced a ‘multi-million-pound contract to enhance [the] Royal Navy Type 45 fleet resilience’. It seems in this context, the MoD are treating ‘fix’ as synonymous with ‘enhance’.

The Power Improvement Project (PIP) is classed as a ‘major conversion project’, and all ships should be ‘improved’ ‘by the early 2020s’.


Over two decades after the programme began, the Type 45 destroyer will be fit to project and protect the UK’s interests. The problem the ship has faced is rooted in a political decision, and is in no way indicative of any Royal Navy incompetence.

Despite the problems, one mustn’t lose sight of the fact that the platform is remarkable in a its capability. Within the next 5 years we’ll see each Type 45 repaired and returned to operations, hopefully in time for HMS Queen Elizabeth’s first operational deployment early next decade.


  1. The issue that I have with the Type 45 is not that its power-plant does not work correctly which is bad enough it is something much more important, its primary task.
    The primary task of the Type 45 is to act as an AAW escort for the carriers which will see the first carrier battlegroup operational by about 2023. By this point the Type 45 would be almost 15 years old, the design over 20 years old and the concept almost 30 years old. If we assume that the ships would have a 30 year like span, that new ones takes about ten years to design and then a further five to eight years to build it would mean that we would need to start work on a new design by 2020 which is only two years from now.
    The next issue with that is where would they be built, although the type 26 production would probably be coming to an end unless there is delays in the batch 2 order and the type 31s should have been completed unless there is a larger order the new type 46s that’s what I’ve called them would probably need to be started by 2030. The cut over margin is to small, it will only take a delay either in production or ordering of the batch2 type 26s or type 31s to cause a massive delay.
    This is what happens when there is only one shipbuilder for this type of complex platform.
    I hope that the MoD and the Government in general have not lost sight of this issue.

    • I don’t think the problem is as bad as you make out. The T45 is so advanced that it is likely to still be a very viable platform for quite some time. Plus there is nothing stopping the design process starting in 2020. The general way it works is that a general requirement is stated, the design teams start thinking about the basic design of the vessel. Then as more specifics are nailed down the designs are modified. A cast iron spec will not be needed by 2020. By the time they need building there will be capacity to do so. Plus there is not just a single builder for these ships.

      It is highly likely that at some level there have been talks about the next ship to replace the T45.

    • Would it be viable to redesign the type 26 In to an AAW frigate and they could then supplement/replace the T45? Would the Sampson radar be able to be miniaturised to fit the T26 or could we just buy the aussie cefar and but more weaponry for AAW on it?

    • That makes it pretty new in AAW destroyer terms The USN Arleigh Burke’s are 30 years old based on a 50 year old concept and they are being replaced by more Arleigh Burke’s.

      If there is a complaint to be made about T45 it’s that they are stilll fitted for but not with too many features and they desperately need strike length launchers for ABM and land Attack. Also needs a decent ASM.

    • The National Shipbuilding Strategy has the decision point for t45 replacement in 2022-2023 time frame with IOC around 2035.

  2. I have some sympathy for your argument. By the time new engines are fitted to Type45’s, we could save that portion of the budget and pay less to build Type 46. The business case would shout yes, build new ships, and the MOD will probably say no!
    Somewhere in between may be the answer. I’ve put forward a suggestion that the UK Government builds a new shipyard to accommodate bigger vessels; such as the new Solid Support Fleet. This very same yard could handle the Type 46’s once the SSF’s is completed. This issue of finding a yard to accommodate large vessel should be addressed urgently. One major advantage to building a new yard is the possibilities of building commercial ships once the naval programmes are completed? The SSF is now very likely to be built abroad, which denies the British ship construction vital business and skill building. I’m convinced a brand new large yard could be built as a joint venture between the UK Government and industry.

    I would also recommend Type 46 be a larger variant of Type 26 in order to save design and development time, and save a huge amount of money in the process. Remember type 42’s, which were lengthened to allow for greater weapon flexibility? If Type 45 re-engine programme goes ahead the Type 46 could well slip into the mid-thirties. The Type 26 based Type46 could deliver a brand new destroyer fleet to the RN, in a much quicker timeline. Of cause, the thorny issue of the budget will determine the final outcome?

    • To build commercial ships the UK yards would have to be competitive. They are not and probably never will be.

      Harland and Wolff are a good example. They have the infrastructure to build very large ships. Yet they are merely using their dry docks to carry out repairs rather than new builds.

      Cammell Laird can build large ships (as seen with the sir david attenborough) but are not filled with orders from the civilian market.

      • Don’t accept the easy answer of the UK not being competitive. However, my plan would be to build a large dock preferably covered, to build the Solid Store ships and build up skills on large vessels. Once the naval programmes are completed, to go out and compete for contracts globally. We must as a nation get back to shipbuilding, a business where we were once supreme.

        • So if the UK is competitive then why are virtually no commercial large ships built here?

          Again, we do not need a new dockyard built. We already have some of the largest dry docks on earth and they are not being used to build ships!

          It is not the easy answer it is simply a fact.

          • I not saying we are competitive, I’m saying we should be and no, we don’t have yards available to build large vessels at this time.

          • The UK is unable to and unlikely ever to be able to build large commercial ships competitively.
            BAE in Glasgow have a monopoly over building surface warships of destroyer size.
            The margins and delivery times for commercial vessels are very tight and the major building yards are booked well in advance and the production schedules brook no delays unlike warships who take an eternity to build.
            BAE and the Unions building warships have no incentive to speed up the process.
            We are therefore stuck in this MOD, BAE spiral.
            Recent RFA vessels built in Korea were never tendered for in UK and the basic vessels were finally outfitted with UK supplied comms.defence and RAS equipment.which was good value for taxpayer and adequate vessels for RN replenishment and supply.
            The future Royal Marine landing craft and helicopter carriers are not sophisticated craft and there is no reason why they cannot be built in approx.two years.
            Similarly if type 31e destroyers are to be built for RN and export, then a lot more efficient building system will need to be devised and other UK yards will need to be revitalised and brought into operation because the Glasgow yards are fully occupied with type 26 and smaller warships.
            Radical rethink is necessary.

        • The problem is not for the lack of skilled labour it is the associated costs. We simply cannot compete with the likes of China were there labour force is paid a pittance. Our saving grace is that if a ship is built here it has to pass a quality checks otherwise Lloyd’s wouldn’t certify it. Would the issues with the batch2 Rivers been found if they were built by a foreign yard. Would there be a penalty for the manufacturer.

      • Ship repair is more profitable and a lot less stressful than new builds.
        A big vessel new build could be in a dock being put together as super blocks for 12 months + on a contract worth 100 mil for the actual construction portion.
        Doing a big vessel in a graving dock every 10 days for painting and underwater work can earn the same money or more over the same 12 month period. Plus you also get the alongside work and growth margin on repair jobs which you don’t on new builds.

  3. Arleigh Burke class will have a production run from the late 1980s to least 2050.

    The design is continuously being upgraded and modified.

  4. Similar thing happened to the F4K/M Phantoms the RAF & RN got in the 60’s. They had RR engines instead of the original J79 US engines, which meant some redesign of intakes and other aspects, as well as UK avionics instead of US kit. Pretty certain in the case of the engines it was to support UK industry.

    I’d thought the Spey engines caused a loss of performance across the board but according to this :- there were a number of improvements.

    “In replacing the original General Electric J79 engines with the larger Rolls Royce Speys (RB 168-25R Spey Mk 202/203s), the fuselage and the air intakes needed to be enlarged; the installation of the Speys gave an increase of 10% in operational range, 15% increase in ferry range and better low-level acceleration, however the increased drag of the engine installation resulted in slightly reduced performance at high altitude”.

    • The UK phantoms were the most expensive and slowest ever built.

      There was a hope at the time that the US navy would adopt a Spey engines for a new F4 version (the US had already chosen Spey for the A7D and E) alas they had there eyes on a bigger prize the F14.

      The RAF should have gone for the F4E.

      • Mike, the F4E’s puny radar never met the RAF’s needs.

        They should have just bought F4D’s, perhaps license assembled at Wharton.

        The F4 K was another great British cock up, as you say the most expensive and slowest Phantoms in the world.

        But after a series of cancellations, followed by French AFVG cancellation, the government were desperate to include UK content …

        • I’ve asked about performance from an ex RAF Phantom pilot – I’ll post what he tells me …

          I remember Pierre Sprey talking about the tilted up wings and tilted down tailplane being aerodynamic sticking plaster. He wasn’t just referring to the RAF version.

          • The UK’s Phantom were given more powerful Spey engines so they could be launched from the relatively small deck of HMS HERMES, when it was still the intention to operate her as a conventional fixed-wing carrier into the 1980s.

  5. Cammell Laird, I understand has the contract to fix the engines under the guidance of BEA systems. Not sure has the first ship gone to Merseyside yet?

  6. The Type 45 is also the first of it’s kind to be designed to be totally upgradable, it has huge growth potential, one reason why it is so large, it will be much easier to upgrade and remain cutting-edge for many years to come. This was designed in mind from the very start, unlike it’s predecessor the, T42.

    • ‘ one reason why it is so large’

      I was in the ops room of the T42 HMS Edinburgh when it was on its paying off voyage. Cables and kit strewn all over the place. As you say one of the reasons the T45 is so much larger than its predecessor.

  7. It’s an interesting article. I’m not convinced there has to be any blame though, every warship designed and built is going to be some sort of compromise, otherwise they’d cost twice as much, take double the crew, and probably be totally unusable. Looking at the F35 that’s a compromise of its various abilities including stealth, performance and utility. Yet it seems to be getting rave ratings at last. In the case of the T45 there happened to be a problem with the engines, and one which didn’t prevent the T45 operating most of the time, or under controlled conditions.

    These things are always stated as “saving jobs”, but I think it would be better to talk about “capability”, in this case the capability of the UK to be able to produce engines. And in that respect Rolls Royce is still capable, in spite of economic difficulties, cost-cutting and relatively smaller total numbers of ships and planes to put them in. Then again with the point of view with it not being just “jobs”, the economic benefit of those jobs themselves and the secondary spending, adds to the UK economy, and therefore reduces the nett cost, though that isn’t cost accounted to the MOD and RN unfortunately.

    If it’s looked at as the capability of the UK to produce engines, you go on to other parts of the ships and planes, then you go on to building the ships themselves, and arrive at the end where you’d always buy off the shelf from some other country.

    Is that what the UK would want to do?

    I can claim a slighly unique perspective as Rolls Royce left Hillington, and as a supporter of Independence for Scotland, I have no axe to grind in keeping “jobs” or capability or economic benefit in what I’d like to be my sole country (currently I have two, Scotland and the UK). And I am aware that this is an argument that could be used against Scotland. In fact it was last referendum: “We only build warships in the UK”. Well, what about the engines?

    • There was also the benefit of increased efficiency and reduced heat signature which probably swung the decision too. Although the parts that are to blame are from Northrop Grumman…

  8. It’s funny how people here shame the decision to buy the untrusted but British engine as a stupid decision and yet the same people are crying out for British built equipment. Can’t have it both ways, either you accept the risk/cost of going domestic or you go foreign.

      • Excellent point, taking a risk on UK developed engine means we can now command more export orders. Sometimes you learn more when things go wrong the right. It also doesn’t mention the WR 21 offers a reduction in fuel burn of around 15% compared to the LM2500, efficiency only decreases in hot climates so most of the time the we’re getting excellent performance and savings. Remember that oil at $150 per barrel and projected to go higher, so efficiency would have been a key driver for the decision.

        • The engine is not the only fuel efficiency driver.

          Better hull paints reduce marine growth so you need less fuel to push you through the water. Hull growth calculations from the power required for a set speed are a mandatory in the RN. If the power increase V a Set speed gets to high its time for a hull clean.

          Improved prop design has helped reducing not just cavitation(Noise) at various speeds but improving the speed derived from the prop for a set power in.

          On the T23 the addition of a transom flap increased fuel efficiency by nearly 10%…10% saving for welding on some plate to extend the stern of the vessel!

  9. Geoff Hoon…why am I not surprised.

    The very definition of the journeyman politician, screwing up every department he touched.

    Complete & total arsehole.

    • Worked his way through a staggering number of houses whilst he was supposed to be busy running a very challenging department. Basically property development paid for by fiddling MPs expenses.
      The thing that concerns me most is that a warship, which is supposed to be able to absorb damage is able to completely “trip out “.How on earth can it have been designed like that if the generators are still capable of running?

    • Far less an arsehole than Fox, and the bloke who was sacked, presiding over the emasculation of all branches of the forces. New Tory chap seems to be doing a lot better, to be fair, but time will tell.

  10. Poorly written article that doesn’t make sense in places and contains a number of major errors.

    But to pick one, the Royal Navy was part of the team that designed the T45 propulsion system and accepted the Type 45 into service without adequate testing.

    So no, the RN does not escape their share of blame.

    • Your comment completely ignores the fact that that ultimately the RN had to accept the political decision to take what was given when it came to propulsion.

      If you think the RN would have been allowed to publicly reject a £1bn destroyer once built, you’re living in fantasy land.

      Like countless times before they simply had to make the best of it.

    • Ron5,

      Thanks for your comment – it would be great if you come email with other major errors and areas where I didn’t make sense ([email protected]) – I’m sorry I came up short.

      Although I will agree with ‘mac’. Politically, the RN cannot simply reject a ship from BAE Systems. The should have tested further I agree, but I very much doubt SoS would allow that to happen.

      As I understand it (Source: Save The Royal Navy), the T45 propulsion system was designed not for the T45 specifically. Rolls Royce designed it, and had a number of ships in mind, including the T45, but I’ve also been told by a source close to the industry that the US Navy had pencilled in the WR-21 as an engine for one of their ships, but later changed their mind. So not entirely sure what you mean by ‘the team that designed the T45 propulsion system’ that the RN was apparently part of, but as ever, more than happy to be proved wrong!!

      Best wishes,

      Henry Jones

      • WR-21 was indeed no designed solely for the T-45 and had infact completed testing around the time the T-45 project began!

  11. You can not really compare the WR-21 to the LM2500. The latter has been in service for years but it isn’t even close one is simple cycle WR-21 is advanced cycle the WR-21 has exhaust recuperation which massively reduces the ships infrared signature but also improves fuel consumption. The WR-21 is advanced the LM2500 isn’t. To say it was hastily designed is also very harsh it had completed testing in 1999 when the project started and was tested for 2 years on a test bed which mated it to the advanced induction motor. So to say it was designed hastily simply isn’t true!

    • To say the “WR21 is advanced the LM2500 isn’t” is to expose your ignorance of these GT engines. I worked both of these programs for many years, each engine has its advantages. The LM2500 uses far more advanced hot section materials as compared to the WR21. The LM2500 has incorporated more than 370 engineering advances since its inception, the WR21 only has a dozen. To think engines are only representative of the year they were introduced is to not understand product devleopment.

  12. I am still trying to figure out how BAE built an IEP hull that sounds like a concrete mixer underwater. And why do conventional Horizons generate more electric?

    As for the prime mover, well sometimes the best choice is to buy from outside. It isn’t as if we don’t invest an awful lot home supporting the nuclear submarine program.

  13. Wikipedia seems to document a somewhat different perspective of WR-21 and to lay all responsibility on RR seems a little off the mark given Northrup Grumman’s prime contractor role for the WR-21 as well as providing the intercooler and recuperator that seem to be at the core of the issues.

    Why the turbine was chosen seems to have been driven by the expectation of significant cost savings due to increased efficiency with a 30% lower fuel burn. The turbine itself was based on RB211 and Trent engines which were well proven platforms.

    So the decision was hardly lunacy. It was a riskier selection with a potentially significant benefit that failed to materialize, or perhaps more accurately the benefit may be there but has been offset by the cost of problem rectification. Can’t always be safe in warship design or we’d still be building Dreadnoughts or wooden ships with masts.

    • Excellent comment balances the article. It is clearly not the R.R. engine but the associated systems that has been the issue. I note these ships are ‘out and about’ even so. The day this country builds equipment for its armed forces everyone likes has not dawned.

  14. Could we not buy some more T26’s and modify them into an AAW role? Would probably save us having to redesign the wheel in 10 years time for a T45 replacement. The T26 looks as though it’s been made big enough to fit with upgraded kit.

    • As previously posted above the National Shipbuilding Strategy has the decision point for T45 replacement in 2022-2023 time frame with IoC around 2035. If kept to that schedule then T45 replacements would seem to start being built before T26 has finished given current T26 build rate … or maybe it would dovetail perfectly to support a follow on AAW variant.

      However, T26 is already very expensive. So one question might be whether an AAW version would come in at significantly lower cost, assuming continued export success reduces amortized R&D per hull, or not. It would have the benefit of a state of the art quiet hull and potential dual capability for leading edge ASW though.

      Alternatively, if the Arrowhead 140 platform wins the T31e contest then that hull already supports a very capable and relatively low cost AAW solution which might enable a significantly lower cost solution for the same number of hulls.

      Seems for MoD and RN it would be nice to have options.

  15. You’ve got to laugh from 1500hrs Tuesday:
    “Portsmouth £1billion Royal Navy ship HMS Diamond needs repairs again”
    Portsmouth Type-45 destroyer HMS Diamond is said to have been guided in by three tug boats after suffering an engineering malfunction miles away from Devonport……The latest problem left HMS Diamond without power shortly after setting sail from Plymouth. She was forced to send an urgent message for assistance.

    Read more at:

  16. Interesting I saw something yesterday which I had never heard before. In the early years the US and the company were so desperate top get the Boeing 747s into operators hands that they flew with extremely unsafe engines with the most appealing reliability record and a very high risk of shut down during a flight. The Boeing argument to its Government and safety regulators was that having 4 engines it was still safe to fly despite these risks.

    In reality every programme has its risks in particular military ones. Virtually no American program doesn’t have its problems, cost over runs lack of early reliability and numerous other problems no wonder they are sticking with the proven Arleigh Burke Destroyers. If you go for safe and proven all the time you never move ahead and you lose your own capabilities, the French understand that far more than we do however we are state of the art in criticising our own problems while ignoring those of the very nations we would be buying from and once they have destroyed our capacity to build alternatives would start to up the costs of all those products that they wish to sell us. British industry to a great degree and certainly below the top end we still excel in has disappeared because we stuck with tried and tested and did not innovate and take chances which historically had built our industrial base. Wanting more of it is hardly going to help matters and as has been explained above the very work on these engines has led to the production of a follow up product that is now best in class. Well worth it I would say.

  17. German warship lists. Spanish sub too heavy, so make longer to increase buoyancy and now won’t fit in the designated port. American lCS unmittigated disaster.

    Making complex machines is not easy and in the case of the WR21 I still blame the intercooler from Northop Grumann, who seem to have got off with very little criticism.

    The future destoyer should be a refined T45 hull with MT30 engines or an expanded T26 hull. These are known quantities.

  18. Sad indictment all in ship problems stem from past labour government delays short sighted ness sheer stupidity at all design build stages lack of computable in oversight has left arm short of half cocked ships which are faulty under armed and safely only com e fixed when near scrapping time just like queen Elizabeth class carriers over cost late u fit for purpose government cutbacks in defence whilst fighting two wasted wars and brown Blair’s gross incompetence level in looking second rate

    • Your comment is a garbull rant, coming from a Pro Kremlin Clown!
      With No substance Whatsoever!!
      Go back to school to learn grammar!


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