Putting the Type 45 propulsion problems in perspective

Amongst informed defence commentators it has been an open secret for several years, but on 29th January a BBC report finally put the engine problems of the Type 45 destroyers into the public eye. The MoD has consistently played down the seriousness of the issue, that had on occasions resulted in total propulsion and electrical failure, leaving ships dead in the water. Even Parliamentary questions were met with vague assurances that “progress was being made”. The media coverage has since been predictably excessive, giving the unfortunate impression that Type 45s are £1Billion cripples. Although these breakdowns have hampered their operation, all the Type 45s have completed major deployments and HMS Defender is currently on a 9-month Gulf and Indian Ocean deployment.

The problem

The Type 45 uses a pioneering system called Integrated Electric Propulsion (IEP). There are many advantages associated with IEP, fuel efficiency, flexibility in locating the engines and a supposedly reduced maintenance and manning requirement. In basic terms, two WR-21 gas turbines (GTs) and two Wartsila 2MW diesel generators provide AC power for the motors that propel the ship as well as the power for the ships systems – weapons, sensors lighting etc. The WR-21 GTs were designed in an international partnership with Rolls Royce and Northrop Grumman Marine Systems. The turbines are of a sound design but have an intercooler-recuperator that recovers heat from the exhaust and recycles it into the engine, making it more fuel-efficient and reducing the ship’s thermal signature. Unfortunately the intercooler unit has a major design flaw and causes the GTs 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.

The MoD has not revealed how frequently these blackouts have occurred but the first 2 ships, HMS Daring and HMS Dauntless seem to have suffered the most. The first indication of problems was as far back as 2010 when it was admitted HMS Daring lost all power in mid-Atlantic and had to be repaired in Canada. Although the Type 45s have been active, some significant commitments have been missed. An indication that all is not well could be seen by the number of Type 45s alongside in Portsmouth at any given time during the last few years. Historically the RN has never been a fleet of ‘harbour queens’ and today’s over-worked navy can ill-afford unreliable ships. HMS Daring entered service in 2009, it has taken more than 6 years to agree to deal with the problem and it will probably be well after 2020 before the work is completed. It is obviously dangerous from a seamanship and navigational point of view to suddenly lose propulsion at any time. It is even more serious when operating in a high threat environment as the ship would be a sitting duck.

The otherwise highly successful Type 45

Great credit must go to the RN’s long-suffering mechanical engineers who appear to have always been able to restore power fairly quickly. The MoD states that “A Type 45 has never been forced to return to port because of a lack of power or propulsion.” As in so many other cases, the RN has managed to work around the problem to some extent and find fixes that reduce the number of electrical failures. Under normal circumstances the Type 45 propulsion system provides exceptionally good acceleration, smooth, quiet operation and fuel efficiency almost double that of their Type 42 predecessors. When the Type 23 Frigates first entered service they lacked a computerised command system, a similarly serious flaw in a new warship. There was determination that the Type 45 would have the best command system and expectations have even been exceeded. The Type 45 has become the ‘gold standard’ in air defence and air traffic management, it has become the “goalkeeper of choice” for US aircraft carriers who recognise it has the edge, even over their renowned AEGIS system.

Despite the issues, the Type 45 is one of the best air defence ships in the world, they have travelled thousands of miles already and proven themselves in diverse roles. The propulsion problems will be fixed and the platform has the capacity for major future upgrades.

A radical cure

A feasibility study into upgrading the generators was completed by BAES and the MoD in March 2015. The funding for the “Type 45 machinery improvement package” was agreed in the November 2015 SDSR and at least the problem has finally been recognised and funds are in place. Each vessel will have to be dry-docked, large openings cut in the hull and one or possibly two new diesel generator sets slid into place.

Type 45 destroyer propulsion arrangement

Type 45 destroyer propulsion general arrangement. Removing and replacing the diesel generator sets would appear to present significant work. Image: Rolls Royce.

Replacement of the WR-21 GTs is not a practical option. Instead additional or more powerful diesel generators will provide long-term redundancy and assurance that electrical supplies can be maintained in the event of GT failure. The good news is that the large Type 45 design has the space and reserve buoyancy to cope with larger or additional diesels. The rectification work on the six ships will be done one by one as part of the normal major refit cycle. This will extend the length of the refits but should not have an especially dramatic effect on frontline availability.

A pioneering legacy

It is ironic that the RN is suffering with propulsion problems, having had a great history of propulsion innovation and success. The steam turbine was a British invention and in HMS Dreadnought (1906) was the first capital ship to use this leap in propulsive power. The steam turbine drove the majority of major warships for the next 60 years. HMS Amazon (1974) was the first all-GT warship and British engines were subsequently exported to many foreign navies. Much of the world-renowned expertise in naval GT design was derived from an obscure and secretive facility, the Pyestock National Gas Turbine Establishment at Farnborough which tested & developed marine and aero engines until it was closed in 2000. One of Pyestock’s last projects was some of the initial development of the WR-21 done in partnership with Rolls Royce and Northrop Grumman. Reliance on computer modelling signalled the end for Pyestock but with hindsight perhaps there is no substitute for ‘real world’ testing. It is interesting to note that recently Rolls Royce opened a brand new testing facility for the WR-21 and the MT-30 GTs (Which will power the QE aircraft carriers and Type 26 frigate).

Culpability and compensation

“BAE Systems, the prime contractor, ran a competition to select the pair of gas turbines that will power each warship. Excellent bids were received from Rolls Royce plc, offering the WR-21, and from General Electric Company, offering the LM2500. The prime contractor advised us that both engines met the programme requirements, and that either would be acceptable to the Royal Navy. Therefore, it has been a difficult task to decide between the two bids. On balance, we have decided to select the Royce WR-21. The LM2500 is a mature product — it is in volume production and available at an attractive price. We accept that the WR-21 presents a greater degree of risk to the programme, but we had to look at a range of other factors. Those factors, many of which fall outside the type 45 programme, include the commonality of support arrangements with existing Rolls Royce engines in the Royal Navy, and particular aspects of Royal Navy fleetwide operations for which the Rolls Royce engine is well suited.”
Geoff Hoon, Secretary of State for Defence, House of Commons, 1st November 2000

Essentially the Labour administration of the time took a calculated risk that untested British GTs would be a better bet than a tried and trusted American option. The British jobs benefits, together with apparent efficiency gains offered by the WR21 made it an attractive political proposition. Although Geoff Hoon is considered to have been something of a blundering Defence Minister, in this instance it was not an unreasonable decision, especially given the good track record of UK GT innovation. BAES could quite reasonably claim in court that they simply advised the client who took the more risky option. However BAES has not made any gesture of goodwill and have not funded any rectification work on the Type 45 Destroyers. Meanwhile they benefit from on-going an in-service support contract for the Type 45 which had already cost the taxpayer £370 million by 2014. Whether Rolls Royce or Northrop Grumman will accept any legal liability seems unlikely and it will be the poor taxpayer will be footing the bill. This unplanned expenditure is also likely to further delay any plans for fitting MK41 Vertical Launch Cells that would allow the Type 45 to carry Tomahawk or SM3 anti-ballistic missiles.

A reflection on the state of UK industry?

There are growing signs that frustration with industry in the MoD has reached breaking point. The Type 45 propulsion problems are just one of many expensive problems with major defence contacts. The cost over-runs of the Astute class submarine have led to Whitehall creating a special project office to manage the Trident Successor submarines and failures will be met with harsher financial penalties. The surprise emergence of the alternative frigate programme, in addition to the Type 26, is also a sign of disillusionment with late, expensive and flawed offerings from BAE Systems.

In a wider sense, the UK defence-industrial malaise is the result of successive governments failure to think strategically and place regular orders that would ensure continuity of employment and the engineering skills base. It is also perhaps a reflection on a society that does not encourage enough young people into science and engineering. Attainment of celebrity, careers in media, sport or entertainment are over-valued, far above those of designers, engineers, technicians and scientists upon who we rely for our way of life and military power.