Type 42, a flawed but long-serving design

Borne of a political decision that affected UK defence policy for years, the Type 42 guided missile destroyer would go on to serve the Royal Navy successfully for almost four decades.

When, in 1966, the UK government of the day cancelled the CVA01 aircraft carrier project, the ramifications were widespread. Not only would the Fleet Air Arm be reduced to just flying helicopters for many years until the arrival of the Invincible class carriers and the Sea Harrier, the need for the Type 82 guided missile destroyer disappeared.

The Type 82 was already considered to be too expensive and the original planned number of 13 was first reduced to eight and in the end just one, HMS Bristol, was built at a cost of £24.2 million by Swan Hunters, completing in March 1973.

The Type 42 design was seen as a cheaper alternative that could be built for a unit cost of no more that £19 million per hull but it soon ran over budget. To keep within the planned budget, the first two batches had 14.25m removed from the original design’s bow section, forward of the bridge, as length is the most expensive dimension. This resulted in the need to squeeze everything needed into a much-reduced space.

The sole Type 82 guided missile destroyer, HMS Bristol, laid up in Portsmouth harbour after decommissioning from a training ship (Credit: Author’s collection)

Design

The requirements as finalised included a helipad aft, a large and complex radar system fore and aft, a Sea Dart missile launcher and 4.5in gun forward, and arrangements amidships for air inlets to the gas turbine machinery. The interior was cramped compared with later designs. Complement for Batch 1 and 2 ships was up to 312 on a full load displacement of 4,350 tons while that of its successor, the Type 45, is 285 on 8,500 tonnes.

All were propelled by Rolls Royce TM3B Olympus and RM1C Tyne marinised gas turbines, arranged in a COGOG (combined gas or gas) arrangement, and driving two five-bladed controllable pitch propellers through synchronous self-shifting clutches and a double-reduction locked-train gear system. Four Paxman Ventura 16YJCAZ diesel generators, each rated at 1MW, provided electrical power. 

Lead yard for construction was the Vickers Shipbuilding, Barrow-in-Furness, which built three, with others built by Cammell Laird (four), Vosper Thornycroft (three), and Swan Hunter (four). Two additional examples were built for Argentina, one at Vickers and the other in the home country.

Lengthen but strengthen

The first six ships (Batch 1) entered service between 1975 and 1979; next to complete were the four Batch 2 ships (1980 to 1982) which had identical dimensions but featured some modifications. In service the first 10 experienced problems resulting from the short hull. As a result, to make for a drier foc’sle and improve interior space, the last four ships (Batch 3, delivered between 1982 and 1985) were lengthened forward by 15.5m and with a slight increase in beam. However, the longer hull resulted in a weakness in longitudinal strength and to compensate an external girder was attached on either side of the hull at main deck level.

The last, and most expensive Type 42 guided missile destroyer was HMS Edinburgh which was a longer Batch 3 variant with external hull strengthening (Credit: Harland Quarrington, Ministry of Defence photographer)

Operations

The Type 42 was initially seen as providing area defence for carrier battle groups but would go on to serve in a multitude of roles. They would be operational from 1975 to 2013. First to complete was HMS Sheffield at a cost of £23.2 million and which would be lost in the Falklands on 4 May 1982. The sistership HMS Coventry, was also lost in the conflict, on 25 May 1982. The remaining 12 ships would serve through to 2013, the last to be delivered was HMS Edinburgh, completed in 1985 at a cost of £130.6 million and highlighting the cost escalation over the intervening 10 years. She would be the last to be decommissioned on 6 June 2013, and all surviving 12 vessels were finally scrapped rather than being sold on to foreign powers. The Type 42 had finally proven to be a valuable addition to the fleet over many years. 

John Barnes is a journalist and author and former editor of Marine Engineers Review.