HMS Wilton (M1116): The World's First Plastic Warship

A World First in Shipbuilding

HMS Wilton holds a remarkably unique distinction in naval history: she was the first warship in the world to be constructed from glass-reinforced plastic.

The Problem Was Not Really Mines

The obvious reason for building a warship out of plastic is that plastic is not magnetic, and that is true and is only half of it. The other half is that by 1970 the Royal Navy was running out of the ability to build wooden ships at all.

The Ton class were wooden. Not quaintly wooden, but seriously and expensively wooden: double-diagonal mahogany planking on aluminium frames, built by shipwrights, of a size and quality of timber that was already becoming difficult to buy in the 1950s and effectively unobtainable by the 1970s. The trade that could work it was dying with the men who had learned it. And wood, in warm water, is food. Ships of this class spent fortunes on rot, on marine borers, on planking renewed, on hulls that had to come out of the water and be looked at every couple of years for the whole of their lives.

Glass-reinforced plastic solved all of that at once. It is non-magnetic, so it does not set off an influence mine, which is the headline. It also does not rot, does not corrode, is not eaten by anything, can be laid up by people trained in months rather than years, and can be moulded in one piece. The question in 1970 was simply whether you could build something that big out of it and have it survive being shot at, run aground and slammed into a North Sea swell for twenty years.

Vosper Thornycroft laid her down at Southampton on 7 August 1970, launched her on 18 January 1972 and finished her on 12 June 1973: thirty-four months, and between one and a half and two million pounds. She commissioned into the 2nd Mine Countermeasures Squadron at Portsmouth on 14 July 1973.

Built to the Ton-class minesweeper design and incorporating recovered equipment from the decommissioned HMS Derriton, her GRP hull gave her a dramatically reduced magnetic signature, making her far more resistant to magnetic mines than any conventional steel-hulled minesweeper could ever be.

The second-hand equipment out of HMS Derriton is not a footnote either. It is the reason the ship exists. A prototype is a hard thing to get money for, and fitting an experimental hull with the engines, generators, sweep gear, guns and fittings salvaged out of a Ton class ship that had already been paid off made the whole proposal affordable. She was, in the most literal sense, a brand new idea wrapped around a set of second-hand parts.

The Pennant Number Had Been There Before

There is a coincidence buried in her number that is worth pulling out, because it is a good one.

M1116 was not a new pennant in 1973. It had belonged to HMS Burnaston, a wooden Ton class minesweeper who happened to be passing through the Suez Canal in June 1967 when the Six-Day War broke out and the canal was closed behind her. Burnaston paid off in 1969 and was sold for scrap in 1971, and two years later a plastic ship took her number.

Clearing the Suez Canal

Assigned to the 2nd Mine Counter Measures Squadron at Portsmouth, Wilton took part in Operation Rheostat in 1974, an international effort to clear mines from the Suez Canal following years of conflict in the region, putting her innovative construction to important practical use.

In 1974 that number went back to the Suez Canal. Operation Rheostat was the international clearance of a waterway that had been shut for seven years and was full of mines, unexploded ordnance and sunken ships, and Wilton was part of it. What the job actually involved is set out in HMS Maxton (M1165) and HMS Bossington (M1133). The pennant number that had been trapped by the closing of the canal came back and helped open it.

Two things missing from her record are worth putting in. The first is Northern Ireland. In 1976 she did seven separate periods of Operation Grenada, the Royal Navy's contribution to the security effort there, which meant patrolling the loughs and the coastal approaches looking for weapons and explosives coming in by sea. Minehunters were good at it because they are small, shallow, manoeuvrable, fitted with excellent sonar and used to working close inshore in the dark, and because a fishing boat with something aboard it does not much want to be looked at by a warship with a searchlight.

HMS Tupperware

Wilton's unusual construction earned her a string of affectionate nicknames among her crew and the wider fleet, including HMS Tupperware, HMS Indestructible, the Plastic Duck and the Plastic Pig, a fond bit of naval humour for a serious piece of engineering innovation.

Jubilee Review and NATO Service

Wilton took part in the Silver Jubilee Review at Spithead in 1977 and served with NATO's Standing Naval Force Channel during 1977 and 1980, and in August 1979 was involved in a collision with the Belgian vessel BNS Breydel near Ostend, part of the routine hazards of a busy operational career.

The Mines Nobody Admitted Laying

The second omission is the strangest episode of her career, and one of the strangest of the whole decade.

In July and August 1984, ships began blowing up in the Gulf of Suez and the southern Red Sea. Not one or two: something close to twenty merchant vessels of a dozen nationalities were mined in a few weeks, in one of the busiest shipping corridors in the world. A group calling itself Islamic Jihad announced that it had laid a hundred and ninety mines. Suspicion also fell on a Libyan cargo ship, the Ghat, which had made a leisurely and unexplained fifteen-day passage down the canal and the Gulf in early July when the trip should have taken eight days. Nobody has ever conclusively proved who did it.

What is certain is that the Red Sea had been closed by an anonymous act of sabotage, and that no navy in the region could clear it. So an international force went: British, French, Dutch and Italian minehunters, and two United States Navy airborne mine countermeasures squadrons flying sleds behind helicopters. Four British ships already in the Mediterranean reached Adabiyah, south of Suez, on 15 August and began work the following day. Wilton was the fifth to arrive.

It is worth noticing what that means for a ship built as an experiment. Ten years after she was completed, the plastic prototype was being sent to the far end of the Mediterranean to deal with a live minefield laid by unknown people, in company with four steel and wooden sisters, because she was as good as any of them and rather better against the thing they were actually looking for.

A Yacht Club on the Thames Estuary

HMS Wilton was retired by the Royal Navy in 1994, and after some years in storage was sold in August 2001, converted into the headquarters of the Essex Yacht Club at Leigh-on-Sea on the Thames Estuary, a fitting retirement for a ship whose entire existence had proven that plastic could do a steel ship's job just as well.

What She Proved

Proving that plastic could do a steel ship's job just as well is the right conclusion and understates the scale of it, because the entire Royal Navy mine countermeasures force is now built the way she was.

The Hunt class that followed her, from 1978, were and remain among the largest glass-reinforced plastic ships ever built by anybody: some seven hundred and fifty tons of moulded plastic apiece, thirteen of them, and HMS Cattistock (M31) is still in service more than forty years on. The Sandown class of the 1990s were the same idea again, and one of them is now the flagship of Estonia. Every dedicated Royal Navy minehunter built since has been made of the same material she was.

Her last job was fitting for all that. From 1991 to 1994 she was a navigation training ship at Britannia Royal Naval College at Dartmouth, taking officers under training up and down the south coast, so that the ship built to prove a point about materials spent her final three years teaching people how to find their way about.

And she is still there, at Leigh-on-Sea, as HQS Wilton. She was bought in 2001, converted over three years and opened as the Essex Yacht Club's headquarters in 2004, and she has been the club's home ever since. There is a quiet joke in it. Every preserved steel warship in Britain is engaged in a slow, expensive and ultimately unwinnable argument with rust. Wilton is not, because there is nothing in her hull for the sea to attack. The one hull in the Royal Navy that was built as an experiment may well outlast the lot of them.