HMS Prince of Wales’s unfortunate breakdown in August 2022 requiring extended repair work has not enhanced the RN’s image and provided perfect fodder for mainstream media always keen to exaggerate problems with aircraft carriers. Here we provide a brief summary of the situation and the ship’s future programme.
Very shortly after sailing from Portsmouth on 27th August a coupling that joins sections of the starboard propeller shaft failed, causing significant damage to the shaft, propeller and some superficial damage to the rudder. The ship was subsequently dry docked in Rosyth inspection and repair. It has emerged the coupling break was the result of vibration caused because the shaft was out of alignment, something that was known about long before the carrier first left the shipyard in 2019. Experts advised the shaft misalignment was “within acceptable tolerance levels” and should not be a problem. The ship was certified by Lloyds inspectors and steamed several thousand miles before the accumulated stress from the misalignment broke the coupling. There is an argument that reliance on the advice of a single expert when the shafts were known to have issues was taking too much of a risk and was the result of a rush to get the ship to sea for political reasons, precisely who bears responsibility is unclear.
On arrival in Rosyth, the port shaft was also inspected and showed similar signs of misalignment damage, requiring sections to be replaced. A new starboard propeller and shaft sections have been supplied by an overseas manufacturer. The initial plan was to complete the shaft repairs in Rosyth and then return to Portsmouth for a Capability Insertion Period (CIP) that includes aviation-related electronic upgrades. Since the shaft repairs have taken longer than expected, the CIP was started in Rosyth so as not to cause further delays. The CIP is now the greater part of the work and the remedial work on the shafts is likely to be completed ahead of the CIP. The cost of repairs, (excluding CIP which was budgeted for and planned long in advance) is expected to be approximately £25 million.
The Daily Mail article published on 23rd April claiming that PWLS has been “reduced to acting as a scrap yard to keep sister ship Queen Elizabeth afloat” is juvenile clickbait and a distortion of the facts. In an ideal world, the RN would have a complete inventory of spare parts for all of its vessels but budgetary constraints mean that spares are taken from non-active vessels to ensure vessels on the front line can go to sea. STOROB is a routine, if not ideal, practice in most navies and taking selected equipment from PWLS for use on HMS Queen Elizabeth is a sensible short-term solution. This is not an indication that the PWLS has been reduced to some kind of donor hulk and is being cannibalised before she is scrapped. Equipment is not “ripped out” in haste, rather it is very carefully removed and transported to the sister vessel.
Many of the parts manufactured for the aircraft carriers (and indeed most naval vessels) are bespoke designs produced in very small numbers and it can be very expensive or impossible to obtain replacements at short notice. It is a prudent use of limited funds to remove the part from a ship that does not immediately need it and move it onto a frontline platform. The replacements will then be cheaper as the supplier has more time to manufacture them. In the case of some particularly expensive items such as parts for the Type 45 destroyers, new spares will not be purchased at all and they are cycled between ships of the same class as they move between operations and upkeep. This kind of STOROB is not a permanent long-term solution for the two aircraft carriers when it is planned to have periods when both ships will be operational and new spares will have to be purchased.
In the case of QNLZ, the two main items transferred from her sister ship were fuel coalescer filters and the chains used in the aircraft lifts. The filters are used to coalesce very fine water particles that may be present in the fuel into larger droplets than can then be removed more easily. The MT 30 Gas Turbines require fuel of extreme purity.
HMS Prince of Wales will return to Portsmouth in the next few months for some final maintenance work and the RN is confident she will be ready to begin her programme in August. This will almost certainly include the Westlant23 deployment where she will cross the Atlantic and conduct the much-delayed final round of flying trials with US-based F-35 jets. The DT-3 programme will include more advanced testing of shipborne Rolling Vertical Landing (SRVL) which will allow the F-35B to land on the ship with unused weapons or heavy fuel loads.
HMS Queen Elizabeth will sail in mid-May ahead of the CSG23 deployment in the summer. Details of this trip are not yet in the public domain but it is believed that the Carrier Strike Group will be sent to join NATO operations the eastern Mediterranean, although not expected to go east of Suez this year.
The RN does not provide a running commentary on the specific details of vessels undergoing repair but the MoD has not delivered a very proactive communications strategy explaining the issues with such a high-profile ship or robustly promoted the aircraft carriers’ utility more widely. Some have speculated this may be to do with internal service rivalries around the future of carrier strike. It would be daft to pretend this episode is anything but embarrassing, costly and detracts from the otherwise fine engineering achievement of the QEC design and construction project. However, the acquisition and maintenance of aircraft carriers is never easy and there are plenty of far worse examples of issues experienced by foreign navies.
After a period of lower profile activity and enduring a series of negative headlines, the summer and autumn should see both carriers return to action with jets embarked. Next year HMS Prince of Wales will take over as the fleet flagship and high readiness carrier as HMS Queen Elizabeth prepares for her first major refit.