The Ministry of Defence have confirmed that all Type 45 Destroyers will have received upgrades to their power systems by the mid-2020s.

In 2016 it was revealed that due to a design flaw on the Northrop Grumman intercooler attached to the ships Rolls-Royce WR-21 gas turbines, power availability was diminished considerably when functioning in the warm climate of the Persian Gulf; and it quickly became apparent that the class was not operating as originally envisioned with some losing power mid-deployment.

Therefore a planned refit was scheduled from 2019–21 to fully resolve the problems with the six ships in the class.

Jeremy Quin, Minister for Defence Procurement, stated:

“HMS DAUNTLESS, the first of class to undergo the Type 45 Power Improvement Programme (PIP), is expected to complete the initial phase of the installation by Q3 2021. This follows reassessment of the programme to account for the impact of the COVID-19 pandemic on progress. The next phase of the programme will see DAUNTLESS undertake a rigorous trials programme in harbour and subsequently at sea.

The programme is dependent on the availability of ships to undertake the upgrade, balanced against the Royal Navy’s standing and future operational commitments. It is still the case that all six Type 45 ships are expected to have received their PIP upgrade by the mid-2020s.”

What’s the issue?

According to NavyLookout here, the vessels WR-21 gas turbine itself is of a sound design, however, the intercooler unit “has a major design flaw and causes the WR-21s to fail occasionally. When this happens, the electrical load on the diesel generators can become too great and they ‘trip out’, leaving the ship with no source of power or propulsion.”

Putting the Type 45 propulsion problems in perspective

The First Sea Lord, Admiral Philip Jones, clarified in evidence to the Defence Committee that the “WR-21 gas turbines were designed in extreme hot weather conditions to what we call ‘gracefully degrade’ in their performance, until you get to the point where it goes beyond the temperature at which they would operate… we found that the resilience of the diesel generators and the WR-21 in the ship at the moment was not degrading gracefully; it was degrading catastrophically, so that is what we have had to address”.

The Ministry of Defence is funding the Type 45 Power Improvement Programme. The current contract value is approximately £189 million.

 

 

 

George Allison
George has a degree in Cyber Security from Glasgow Caledonian University and has a keen interest in naval and cyber security matters and has appeared on national radio and television to discuss current events. George is on Twitter at @geoallison

46 COMMENTS

  1. I for the life in me, cannot understand how a top of the line class of ships, not only suffered such a fault, but that it will take so long (Almost twice as long as WW2) in which to resolve it. But good to see an end date in sight On that note, I’m pretty sure I read somewhere that when the ships were designed they left out the sound damping for the engines as some wonk at the MOD decided that the threat from subs was no longer an issue. So presuming what I read was correct, has that act of stupidly been resolved as well.  

    • It does seem to have dragged on doesn’t it. That’s a lot of money too, someone should be on the naughty step for this. Doubt it though.

      • The list of procurement cock ups is a long one. The MoD system needs to be overhauled and some attitudes seriously adjusted.

    • Hi farouk,

      I have had a quick dig around on the interweb. The noise issue was first highlighted by the Telegraph I think. However, there was no mention about the speed at which the noise was associated. At 30 knots any ship or sub is noisy and given the T45 isn’t a ASW platform I would expect it to be noisier than a T23 or T26. However, at 8 knots I would hope it could at least be ‘reasonably’ quiet.

      Apparently the original article claimed that the Russian subs could ‘hear’ the T45 100 miles away. Not sure about that at low speeds. Noise, especially low frequency noise, can travel huge distances underwater obviously so possible at high speed..?

      The other things to note is that the T45 was expensive enough with the top class AAW system fitted, adding hull quieting systems would have pushed the cost up even further. Also the T45’s primary role is escorting the QEC and carriers are noisy, very noise when launching jets. Pretty sure submarines would be popping up and complaining about the noise from miles around! (Paraphrasing the Crual Sea 🙂 )

      Cheers CR

      • Hi CR, problem with the T45’s is they have always been noisy units, across the speed range when compared to their predecessors (T42). This was discovered during first of class noise trials and has followed them round ever since?
        I’m not sure what remedial work has gone into improving this, given that they have all had refit/docking periods. Suffice to say they are quieter now then they were, but still not great. We always used to detect them before any of the other warships, bar on occasion the RFAs, so never a good thing.
        You may be surprised to know that carriers, well US CVNs aren’t really that noisy, air ops do not have a great impact WRT noise transmission, as most follows the path of least resistance which is through the air. You have to be really close to know that aircraft are being launched whilst sat at 100m or deeper.
        Noise wise, the weak link are always the HVU’s (oiler/supply ships), as they are essentially MV’s, but the T45 is a good homing beacon too.

        • Gee they must be really loud! Not heard a T45 yet but had a T42 sail past me once – it was making a huge racket, literally like an airliner on take off. T23s on the other hand are spookily quiet.

    • Hi farouk,

      I meant to say that I was un-aware of any efforts to reduce the T45 acoustic signature and a quick search did not bring anything up online either.

      I guess that with only 6 in service the RN expects them to spend most of their time escorting one of the carriers.

      Cheers CR

  2. I wonder if the updates of the Aster/Camm will be synchronised with each T45 as they each come of their PIPs? Or, will this be on a totally different timeframe and at different place?

    • Hi Quentin,

      I read somewhere that the CAMM upgrade would be done seperately. According to Navy Lookout the first CAMM upgrade will not come into service until 2026. My understanding is that there is still some design work to be done and the RN does not want to slow the PIP down – understandably.

      Cheer CR

      • Thanks CR. I’d like to see them synchronise a ASM upgrade on all the T45s at the same time as the CAMM/Asters. Just to offer some extra punch.

  3. MoD procurements must add penalty clauses to the contracts they issue. Not functioning as advertised is as basic as it gets. Following the current Ajax debacle, it would appear that the entire procurement apparatus needs to be overhauled. As a matter of some urgency.

    • I know there will be those that will shoot me down but in other industries flaws such as this would result in compensation claims via product liability insurance (bad batch) and/or professional indemnity insurance (design flaws) and the door should also he open to a good old latent defect claim given the defect couldn’t realistically have been identified until it did fail

      Often such claims and settlement will be subject to confidentiality (unless it goes to court)

      • If I recall correctly the WR21 power unit was selected for political reasons by the government of the day and went against the recommendations of BAE who recommended the LM2500. As such I don’t think the current government have any recourse against the builder.

        That said as stated the issue isn’t with the turbine itself but I think it still holds true that there is no recourse.

        • WR-21 gamble pays off

          Article Abstract:
          Northrop Grumman Corp, together with partners Rolls-Royce and DCN, has received a contract from the British government to supply the WR-21 gas turbine, which will be used in the country’s Type 45 destroyer program. The WR-21 gas turbine, which was based on Rolls-Royce’s RB211 and Trent aero-engines, is claimed to be the most efficient marine gas turbine in the world. Northrop Grumman is expected to handle the fabrication(?) of the gas turbine while Rolls-Royce will build(?) the gas turbine.

          Publisher: Maritime World Ltd.
          Publication Name: Jane’s Navy International
          Subject: Military and naval science
          ISSN: 0144-3194
          Year: 2000

        • If I recall correctly the WR21 power unit was selected for political reasons by the government of the day and went against the recommendations of BAE who recommended the LM2500. “

          A major reason WR21 was selected is due to political considerations certainly, the then Defence Secretary Geoff Hoon would have been a brave man not to go for the Rolls Royce derived solution considering his Ashfield Constituency had a Rolls Royce production facility in it and his close political and personal connections with Derbyshire.

          As for BAE Systems recommending the LM2500 over the WR-21 that actually isn’t true albeit there are many in the defence commentary sphere who believe that to be true and have angrily responded when I have corrected them on that detail….in actuality the devil is in the detail! What actually happened is BAE Systems appraised both solutions:

          • Westinghouse WR-21 with Diesel backup generators
          • GE LM2500 with backup generators

          Their conclusion was the GE LM2500 was a lower risk than the WR-21 but they recommend both solutions could meet the power and range requirements for the class…they didn’t recommend which solution should be chosen just what the risk was in effect passing the buck to the MOD and making it a political decision.

          You also need to consider the national industrial ramifications of the decision, Rolls Royce was threatening to get out of the ship propulsion business which concentrated the minds of the then Government.

          The irony is I remember back when the decision was made the UK defence commentary sphere was very happy with much web backslapping over how the “right choice had been made to back British”…some of those people are now adamant that LM2500 should have be chosen and have rather selective memories over the matter or their previous enthusiasm for the WR-21.

          The power loss issue was also exacerbated by the decision during the development process to reduce the backup diesel power generating capability to save money, that is the reason why there is space available to install new diesels via PIP…they are going where they should have been in the first place for both WR-21 or LM2500 powered solutions which does raise the suspicion in my mind that this issue would have still cropped up albeit in a less aggressive manner if the latter had been chosen.

          It is not all bad, the gas turbine bit of the WR-21 is good being the RB211 plus the ICR system and its flaws are far better understood now meaning the catastrophic failures are rarer than before. Looking at it from an national industrial basis the Marine Trent MT30 would not have happened if it was not for the WR-21 project keeping the lights on at the RR marine power solutions business. The MT30 is an export success and a real challenger to the market dominance of the GE LM2500.

          • All of the above  👍 

            The issues with the recuperater where addressed probably 4-5 years ago. Some mods to the machinery control software helped to ensure that the lights didn’t go out for the smallest issue. Mods where made to the core and the modded cores where fitted to a number of T45s.

            I worked for 4 weeks with a T45 alongside in the Gulf at the height of summer. Speaking to mates on it at the time they had no failures or TLFs in the 6 months they where away due to hot weather or other issues. Confidence in the systems was much better and they where only using the DG sets for hazardous evolution’s as standby units ( RAS, Entering harbour etc). The rest of the time it was running around on the two GT Alt’s with the board split Fwd and Aft or even on just one GT Alt with DGs on standby.

  4. Why o why has it taken so long after how many t45s have succumbed to this fault were they all not built to the same specification or were they built like the 22s different batches?

  5. Does anyone know what the situation is with HMS Dauntless, as far as I know the PIP work has been done, has it been trialled yet?.

    • I think the PIP is done or almost, but now it is necessary to test it to check if it.

      The big problem is that Dauntless spent +14 months in it instead of 6 months as was expected.

  6. George, just to clarify, the Royal Navy (RN) have stated during a defence committee questioning, that the engine problem is not with the Honeywell provided intercooler, it is primarily with the Ingersoll Rand Energy Systems provided recuperator. These are two entirely different things when it comes to gas turbine generators.

    https://turbotrain.net/images/sf0015.png

    As seen in the above schematic of the WR21. Air enters the 1st stage compressor, it then passes through an intercooler before passing to the high pressure compressor (HPC)/(intermediate section). The compressed higher temperature air is then fed into the inlet of the recuperator. The recuperator takes exhausted air that has passed through the power turbine section. Then through entropic action within the heat exchanger, the inlet air is further heated up. This hotter air is then fed to the combustion burners and on to the power turbine section.

    A gas turbine used for electrical power generation makes use of a pre-cooler, an intercooler and a recuperator. These are all heat exchangers with specific roles within the engine assembly. These combinations have been used for years in the electrical power generation industry. The majority have access to large ponds or use refrigerants for the coolant and to maintain the temperature difference and operating window of the recuperator.

    A pre-cooler, will try to maintain the intake air temperature within a specific operating margin. So it can generate the same power on a cold as a hot day. The pre-cooler will sit in front of the 1st stage engine compressor.

    The intercooler sits behind the 1st stage compressor. Its job is to remove the elevated temperature of the compressed air and thereby increase the density of the oxygen, before it enters the intermediate compressor section.

    The recuperator uses the hot exhaust air that has exited the power turbine section and through entropic action heats up the either air passing through the intermediate compressor section or just before it enters the combustion burner. Some intermediate sections are separated into multiple stages and can be called high pressure compressors.

    This may seem counterintuitive, why heat up the air before it goes into the combustor, surely colder air is better for power? However, it is all to do with energy requirements and the fuel used to make it happen. For really cold air you need a shed load more fuel to get it to burn, as the air is in a passive and non-energetic state. Whilst warm air is already at a high state of energy, so adding fuel to it will make it burn easily. Thus by raising the air temperature as it passes through/after the intermediate section, less fuel is required in the combustor, thereby making it more economical. With the WR21 engine, it can make it least 50% more economical.

    However, there is a fine line of how high the air temperature can get within the engine. Generally due to cost, only the power turbine section makes use of high temperature resistant exotic blade materials. The other sections use a blended high strength aluminium alloy. Though this is changing to include metal matrix alloys, which are lighter, stronger and have a higher melting point as used in the Trent 800 series. To help manage the air temperature within the engine, you can use an intercooler. This not only helps the charge density, but also helps cool the engine, as part of this air is bleed off through cooling channels and then dispersed through individual blades etc. On a ground based power unit, outside pre-cooled air is also used. Therefore, if this air gets too hot, the ability for it to be used for engine cooling is reduced and therefore the engines ability to make high power is also reduced. At a point the engine’s ECU will decide if the internal temperature of the engine can no longer be maintained and then go into either a low power safe mode or turn off.

    The recuperator has a much harder job. It uses the engine’s exhaust air as one of the mediums for one half of its heat exchanger. Where temperatures can be between 800C and 1100C. Then also uses the warm compressed air from the intermediate compressor section as the other medium, whose temperatures can be as high as 250C. Through entropic action of the two mediums passing through the heat exchanger, the inlet air temperature is elevated to 400C and higher, before it’s passed into the combustor. For this to work there must be a very large temperature differential between the hot end and cold end of the exchanger, but also the recuperator itself must be cooled to maintain its integrity.

    The RN/MoD are been very tight lipped over the exact cause of the failure. Stating there’s an issue with the intercooler/recuperator, causing the engine to go into “safe mode”, i.e. shut down. From the press and the RN statement during questioning there has been more talk that the recuperator is the problem rather than the intercooler. However, there is a consensus that says the engine fails rapidly and not gradually over time.

    This could be caused by the intake air that’s being used for internal cooling is too hot, but it wouldn’t cause the engine to immediately fail, as the temperature would rise at a steady rate and throttling back to a low power setting will prolong the time to shut down.

    If the recuperator fails, whereby there is no longer a temperature differential between the hot end and cold end, where very hot air enters the combustor or if there was no heat exchanging taking part, the engine should still function but at a lower efficiency. There will be a point where the air temperature matches the flash point temperature of the sprayed in fuel, which will cause spontaneous detonation. This will cause the ECU to shut the engine down immediately.

    The actual recuperator will have a defined operating limit with the exhaust temperatures it can handle, which is governed by the material specifications, exhaust gas temperature and external cooling. In the past recuperators used to suffer badly from thermal cycling where they would crack and cause fouling on the power turbine. Therefore, if the operating window of the heat exchanger is exceeded due to a failure by a heat cycle fatigue crack or the exchanger’s material failing due to “overtemping” caused by a coolant failure. it is possible debris could fall back into the engine and thereby FODing it or cause debris parts to weld themselves to blades, thereby throwing the blade out of balance. The engine’s ECU would detect these out of limit parameters and shut down the engine. Perhaps one day the RN will release a report on the WR21 troubles to the public, though I doubt it?

    Interestingly, when you look at a MT30 package, it doesn’t look like they use a recuperator, let alone an intercooler?

    • It is my understanding that AIResearch (Honeywell) originally provided both the intercooler and the recuperator but during testing the recuperator was found to be problematical so was swapped for the one from Ingersoll Rand. This was towards the end of testing and not enough further testing was carried out to find there were still problems with the new recuperator.

    • That is a very nice explanation.

      The issue, that you appear to be hinting at. is that the thermal loop does lead to thermal run away above certain temperature/power conditions.

      It is, in a lot of systems, possible to bleed in colder air to prevent thermal run away. Granted it is not thermally efficient…..

      There is also the preconditioning of the fuel to consider so that it’s viscosity -> droplet size -> burn characteristics are regularised.

      • Yes, but not everyone understands thermal runaway. I am sure GB knows the real reason for the failure, but is probably bound by a NDC.

        Today, we are lucky in that these engines are pretty much multi-fuel. The combination of a fuel density sensor and a digital ECU amongst other sensors means the engine can easily be tailored to burn various octanes of fuel without changing a load of components. Gone are the days when you had to pump in 1L of octane booster” for every 50L when visiting a foreign country who used a different grade of fuel.

        In Cornwall there’s a standby gas turbine power generator near Indian Queens. It is generally only used during the summer tourist season. However, about 5 years ago there was a major problem. The engine uses a combination of a pre-cooler, intercooler and recuperator. These are all cooled by refrigerant. The issue they had has was with Seagulls basically with their poo. The evaporator heat exchanger used very small fins to maximise the cooling area. These were getting blocked up with poo which then dried and set like concrete. The evaporator started getting less and less efficient until, the power plant had to be switched off. A team were contracted to clear the poo from the fins, but they couldn’t do it without damaging them. So at a cost of just under £5m a new evaporator had to be purchased.

        They tried putting up nets, spikes and using bird scarers, to stop the birds from roasting on the buildings. In the end they got a licence to cull a few. One of my mates who’s a stainless welder by trade, his firm were contracted with fitting the replacement evaporator. He said the old evaporator looked more like a slab of concrete rather than a giant radiator. It was nearly double the weight and they had to use two cranes to lift it out.

        What got me is that the firm knew about the problem and decided to wait until the generator’s efficiency got below a certain threshold, before actually rectifying the situation, rather than dealing with it at source, i.e. getting rid of the seagulls asap. The actual bill according to my friend was just shy of £10m.

        I am really glad the the RN/MoD have sorted the issue and are also future proofing the ship for further electrical needs, with the fitment of more powerful diesels. It’s just a shame they probably got screwed over in the contract, whereby they had to foot the bill for replacements.

    • The recouperator core that is the issue isnt really that big either . I was surprised how small it was when I saw it. It took I think 2 weeks to dismantle the engine room to get to it, a few days to exchange the troublesome core and another 2 weeks to put everything back together.
      The core does contain some exotic alloys due to the high temps that it is subjected to.

      As DaveyB explains there is a lot of interactions in the whole engine system and these also get tied into the ship wide integrated electrical power (IEP) system.
      Software mods to the machinery control system fixed a lot of the issues. Warnings and errors in the ECU stopped immediately shutting the engine down as the errors did before. This gives the ME watch keepers and the IEP system time to reconfigure the breakers to shift load, bring up the DG sets if needed or to drop shedables ( non essential supplies…240v sockets, 50% lighting, galley, hot water heaters, hotel services) to keep propulsion and weapon systems up.

      T23 and LPDs are not immune to TLF’s (Total Electrical Failures) or PLF ( Partial Electrical Failures) . They happen on all ships from time to time.
      A certain LPD (not mine!) for real/ SAFEGUARD lost all of its machinery control system due to a battery back up system failing during a FOST fire exercise( The back up was the 3rd level of redundancy and you have to really go some to get to that level of failure).
      By quickly ripping out /borrowing some battery’s from the vehicles on the vehicle deck and some jumper leads the system was rebooted and power restored. The issue that caused the loss of the battery back up was quickly fixed with some alterations and mods to power supplies class wide so it couldn’t and didnt happen again.

      Unfortunately the T45 costing a billion a pop, got a lot of bad press over losing power at very inopportune moments.

      • Thnx for the update.

        As ever the anecdotes are priceless.

        You do so much better than the RN press office at giving a real & grounded perspective on things….

  7. Having worked in the MOD for many years the waste and screw-ups seem both inevitable and unavoidable. I console myself by imagining that every extra pound spent equates to someone staying in employment

  8. Sorry about the war-and-peace but, the more I read about issues affecting a whole plethora of MOD equipment the more I wonder whether expanding the escort fleet to 24 (with the T32 class) was a wise move? How I’d love to see a fleet of 24 well-defined, cutting-edge, well supported and well maintained escorts but should the extra money not have been spent resolving issues with the current fleet that need properly sorting …. a lack of missile defence for the QE class (I understand that’s what the T45s are there for but, loose one of your two that are running picket at the edge of a CSG ….. because a sub, able to track its badly sound-proofed engines took it out from distance). I know the lessons learnt from the Falklands were years old but we ignore those many combat proven lessons at our peril by leaving capabilities out of specifications. On the T45 point, speed up the inter-cooler replacement. Then there’s the sluggish nature with which a replacement for Harpoon is taking shape with the prospect of a capability gap. Ballistic Missile defence …. the numbers reduction in combat aircraft for the RAF and penny-pinching over the E-3A replacement to a point where a replacement fleet of 3 seems barely worth it, the slow pace of Challenger 2 replacement (only recently decided), the c0ck-ups with Ajax, not to mention the rate at which Russia and China have outpaced us with Artillery range, anti-drone tech, hyper-sonic missiles, nuclear torpedoes to name a few. Don’t get me wrong, the extra money the current government is injecting is welcome ….. it just feels like successive cutting is coming home to roost. My son is soon to join the RN and I’d like to think he joins an armed forces where everything has been done to make sure he and his colleagues can do their jobs to the best of their ability and not be handicapped or put at unnecessary risk simply because someone said, sorry, can’t afford it!

  9. Why are the MOD spending £189m to fund this upgrade – repair? Sound to me like the ships have never met the design specification. Therefore the liability and costs for repair should be with the designers/shipyard that produced these tin cans.

    • That would happen in any other industry except the MOD it appears.

      I have no idea if such pieces of equipment are supplied with a warranty as such but even if they did get one im sure that would have expired by now leaving zero liability with the designers and builders.

    • The problem is that there are not much competitors in defence space. So who can dictate the contract is the industry not the MoD

      I mean, are you willing to go to Italian, German or French warships for RN to punish mistakes of your own industry know that maybe there will be the risk of no industry at all ?

  10. Why 100,000? If the British Army had 80-90k men (and women, I suppose I must add) and could deploy a large division of, say, 50,000 all up or several “combat brigades” of 6-8,000 and sustain them on operations for prolonged periods of time, why is that not an army when some ME conscript force of half a million that can go to an adjacent country and no further is?
    By that metric France is the only nation in Europe besides Russia (off the top of my head anyways) who can say it has an army. Which is silly.

  11. Because the MoD is a huge organisation with hundreds upon hundreds of directorates, commands, and organisations. Those often have hundreds if not thousands of staff, multi million or billion pound budgets, which require someone of certain rank to head, usually at minimum 1 star or grade 5 CS.

    If you look closer there are not actually that many full Admirals or Generals.
    The officer ranks have been cut along with the forces they command.

  12. £189,000,000? When the US announce a contract they detail the cost as (e.g.) $188,258,375 all in price. Ours are always contracts rounded in millions (or billions). Anyone seen Richard Pryor in SUPERMAN III?

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